xref: /llvm-project-15.0.7/libcxx/include/memory (revision b2c5cab1)
1// -*- C++ -*-
2//===-------------------------- memory ------------------------------------===//
3//
4//                     The LLVM Compiler Infrastructure
5//
6// This file is dual licensed under the MIT and the University of Illinois Open
7// Source Licenses. See LICENSE.TXT for details.
8//
9//===----------------------------------------------------------------------===//
10
11#ifndef _LIBCPP_MEMORY
12#define _LIBCPP_MEMORY
13
14/*
15    memory synopsis
16
17namespace std
18{
19
20struct allocator_arg_t { };
21inline constexpr allocator_arg_t allocator_arg = allocator_arg_t();
22
23template <class T, class Alloc> struct uses_allocator;
24
25template <class Ptr>
26struct pointer_traits
27{
28    typedef Ptr pointer;
29    typedef <details> element_type;
30    typedef <details> difference_type;
31
32    template <class U> using rebind = <details>;
33
34    static pointer pointer_to(<details>);
35};
36
37template <class T>
38struct pointer_traits<T*>
39{
40    typedef T* pointer;
41    typedef T element_type;
42    typedef ptrdiff_t difference_type;
43
44    template <class U> using rebind = U*;
45
46    static pointer pointer_to(<details>) noexcept;
47};
48
49template <class T> constexpr T* to_address(T* p) noexcept; // C++20
50template <class Ptr> auto to_address(const Ptr& p) noexcept; // C++20
51
52template <class Alloc>
53struct allocator_traits
54{
55    typedef Alloc                        allocator_type;
56    typedef typename allocator_type::value_type
57                                         value_type;
58
59    typedef Alloc::pointer | value_type* pointer;
60    typedef Alloc::const_pointer
61          | pointer_traits<pointer>::rebind<const value_type>
62                                         const_pointer;
63    typedef Alloc::void_pointer
64          | pointer_traits<pointer>::rebind<void>
65                                         void_pointer;
66    typedef Alloc::const_void_pointer
67          | pointer_traits<pointer>::rebind<const void>
68                                         const_void_pointer;
69    typedef Alloc::difference_type
70          | pointer_traits<pointer>::difference_type
71                                         difference_type;
72    typedef Alloc::size_type
73          | make_unsigned<difference_type>::type
74                                         size_type;
75    typedef Alloc::propagate_on_container_copy_assignment
76          | false_type                   propagate_on_container_copy_assignment;
77    typedef Alloc::propagate_on_container_move_assignment
78          | false_type                   propagate_on_container_move_assignment;
79    typedef Alloc::propagate_on_container_swap
80          | false_type                   propagate_on_container_swap;
81    typedef Alloc::is_always_equal
82          | is_empty                     is_always_equal;
83
84    template <class T> using rebind_alloc  = Alloc::rebind<U>::other | Alloc<T, Args...>;
85    template <class T> using rebind_traits = allocator_traits<rebind_alloc<T>>;
86
87    static pointer allocate(allocator_type& a, size_type n);                          // [[nodiscard]] in C++20
88    static pointer allocate(allocator_type& a, size_type n, const_void_pointer hint); // [[nodiscard]] in C++20
89
90    static void deallocate(allocator_type& a, pointer p, size_type n) noexcept;
91
92    template <class T, class... Args>
93        static void construct(allocator_type& a, T* p, Args&&... args);
94
95    template <class T>
96        static void destroy(allocator_type& a, T* p);
97
98    static size_type max_size(const allocator_type& a); // noexcept in C++14
99
100    static allocator_type
101        select_on_container_copy_construction(const allocator_type& a);
102};
103
104template <>
105class allocator<void>
106{
107public:
108    typedef void*                                 pointer;
109    typedef const void*                           const_pointer;
110    typedef void                                  value_type;
111
112    template <class _Up> struct rebind {typedef allocator<_Up> other;};
113};
114
115template <class T>
116class allocator
117{
118public:
119    typedef size_t                                size_type;
120    typedef ptrdiff_t                             difference_type;
121    typedef T*                                    pointer;
122    typedef const T*                              const_pointer;
123    typedef typename add_lvalue_reference<T>::type       reference;
124    typedef typename add_lvalue_reference<const T>::type const_reference;
125    typedef T                                     value_type;
126
127    template <class U> struct rebind {typedef allocator<U> other;};
128
129    constexpr allocator() noexcept;                      // constexpr in C++20
130    constexpr allocator(const allocator&) noexcept;      // constexpr in C++20
131    template <class U>
132      constexpr allocator(const allocator<U>&) noexcept; // constexpr in C++20
133    ~allocator();
134    pointer address(reference x) const noexcept;
135    const_pointer address(const_reference x) const noexcept;
136    pointer allocate(size_type, allocator<void>::const_pointer hint = 0);
137    void deallocate(pointer p, size_type n) noexcept;
138    size_type max_size() const noexcept;
139    template<class U, class... Args>
140        void construct(U* p, Args&&... args);
141    template <class U>
142        void destroy(U* p);
143};
144
145template <class T, class U>
146bool operator==(const allocator<T>&, const allocator<U>&) noexcept;
147
148template <class T, class U>
149bool operator!=(const allocator<T>&, const allocator<U>&) noexcept;
150
151template <class OutputIterator, class T>
152class raw_storage_iterator
153    : public iterator<output_iterator_tag,
154                      T,                               // purposefully not C++03
155                      ptrdiff_t,                       // purposefully not C++03
156                      T*,                              // purposefully not C++03
157                      raw_storage_iterator&>           // purposefully not C++03
158{
159public:
160    explicit raw_storage_iterator(OutputIterator x);
161    raw_storage_iterator& operator*();
162    raw_storage_iterator& operator=(const T& element);
163    raw_storage_iterator& operator++();
164    raw_storage_iterator  operator++(int);
165};
166
167template <class T> pair<T*,ptrdiff_t> get_temporary_buffer(ptrdiff_t n) noexcept;
168template <class T> void               return_temporary_buffer(T* p) noexcept;
169
170template <class T> T* addressof(T& r) noexcept;
171template <class T> T* addressof(const T&& r) noexcept = delete;
172
173template <class InputIterator, class ForwardIterator>
174ForwardIterator
175uninitialized_copy(InputIterator first, InputIterator last, ForwardIterator result);
176
177template <class InputIterator, class Size, class ForwardIterator>
178ForwardIterator
179uninitialized_copy_n(InputIterator first, Size n, ForwardIterator result);
180
181template <class ForwardIterator, class T>
182void uninitialized_fill(ForwardIterator first, ForwardIterator last, const T& x);
183
184template <class ForwardIterator, class Size, class T>
185ForwardIterator
186uninitialized_fill_n(ForwardIterator first, Size n, const T& x);
187
188template <class T>
189void destroy_at(T* location);
190
191template <class ForwardIterator>
192 void destroy(ForwardIterator first, ForwardIterator last);
193
194template <class ForwardIterator, class Size>
195 ForwardIterator destroy_n(ForwardIterator first, Size n);
196
197template <class InputIterator, class ForwardIterator>
198 ForwardIterator uninitialized_move(InputIterator first, InputIterator last, ForwardIterator result);
199
200template <class InputIterator, class Size, class ForwardIterator>
201 pair<InputIterator,ForwardIterator> uninitialized_move_n(InputIterator first, Size n, ForwardIterator result);
202
203template <class ForwardIterator>
204 void uninitialized_value_construct(ForwardIterator first, ForwardIterator last);
205
206template <class ForwardIterator, class Size>
207 ForwardIterator uninitialized_value_construct_n(ForwardIterator first, Size n);
208
209template <class ForwardIterator>
210 void uninitialized_default_construct(ForwardIterator first, ForwardIterator last);
211
212template <class ForwardIterator, class Size>
213 ForwardIterator uninitialized_default_construct_n(ForwardIterator first, Size n);
214
215template <class Y> struct auto_ptr_ref {};      // deprecated in C++11, removed in C++17
216
217template<class X>
218class auto_ptr                                  // deprecated in C++11, removed in C++17
219{
220public:
221    typedef X element_type;
222
223    explicit auto_ptr(X* p =0) throw();
224    auto_ptr(auto_ptr&) throw();
225    template<class Y> auto_ptr(auto_ptr<Y>&) throw();
226    auto_ptr& operator=(auto_ptr&) throw();
227    template<class Y> auto_ptr& operator=(auto_ptr<Y>&) throw();
228    auto_ptr& operator=(auto_ptr_ref<X> r) throw();
229    ~auto_ptr() throw();
230
231    typename add_lvalue_reference<X>::type operator*() const throw();
232    X* operator->() const throw();
233    X* get() const throw();
234    X* release() throw();
235    void reset(X* p =0) throw();
236
237    auto_ptr(auto_ptr_ref<X>) throw();
238    template<class Y> operator auto_ptr_ref<Y>() throw();
239    template<class Y> operator auto_ptr<Y>() throw();
240};
241
242template <class T>
243struct default_delete
244{
245    constexpr default_delete() noexcept = default;
246    template <class U> default_delete(const default_delete<U>&) noexcept;
247
248    void operator()(T*) const noexcept;
249};
250
251template <class T>
252struct default_delete<T[]>
253{
254    constexpr default_delete() noexcept = default;
255    void operator()(T*) const noexcept;
256    template <class U> void operator()(U*) const = delete;
257};
258
259template <class T, class D = default_delete<T>>
260class unique_ptr
261{
262public:
263    typedef see below pointer;
264    typedef T element_type;
265    typedef D deleter_type;
266
267    // constructors
268    constexpr unique_ptr() noexcept;
269    explicit unique_ptr(pointer p) noexcept;
270    unique_ptr(pointer p, see below d1) noexcept;
271    unique_ptr(pointer p, see below d2) noexcept;
272    unique_ptr(unique_ptr&& u) noexcept;
273    unique_ptr(nullptr_t) noexcept : unique_ptr() { }
274    template <class U, class E>
275        unique_ptr(unique_ptr<U, E>&& u) noexcept;
276    template <class U>
277        unique_ptr(auto_ptr<U>&& u) noexcept;       // removed in C++17
278
279    // destructor
280    ~unique_ptr();
281
282    // assignment
283    unique_ptr& operator=(unique_ptr&& u) noexcept;
284    template <class U, class E> unique_ptr& operator=(unique_ptr<U, E>&& u) noexcept;
285    unique_ptr& operator=(nullptr_t) noexcept;
286
287    // observers
288    typename add_lvalue_reference<T>::type operator*() const;
289    pointer operator->() const noexcept;
290    pointer get() const noexcept;
291    deleter_type& get_deleter() noexcept;
292    const deleter_type& get_deleter() const noexcept;
293    explicit operator bool() const noexcept;
294
295    // modifiers
296    pointer release() noexcept;
297    void reset(pointer p = pointer()) noexcept;
298    void swap(unique_ptr& u) noexcept;
299};
300
301template <class T, class D>
302class unique_ptr<T[], D>
303{
304public:
305    typedef implementation-defined pointer;
306    typedef T element_type;
307    typedef D deleter_type;
308
309    // constructors
310    constexpr unique_ptr() noexcept;
311    explicit unique_ptr(pointer p) noexcept;
312    unique_ptr(pointer p, see below d) noexcept;
313    unique_ptr(pointer p, see below d) noexcept;
314    unique_ptr(unique_ptr&& u) noexcept;
315    unique_ptr(nullptr_t) noexcept : unique_ptr() { }
316
317    // destructor
318    ~unique_ptr();
319
320    // assignment
321    unique_ptr& operator=(unique_ptr&& u) noexcept;
322    unique_ptr& operator=(nullptr_t) noexcept;
323
324    // observers
325    T& operator[](size_t i) const;
326    pointer get() const noexcept;
327    deleter_type& get_deleter() noexcept;
328    const deleter_type& get_deleter() const noexcept;
329    explicit operator bool() const noexcept;
330
331    // modifiers
332    pointer release() noexcept;
333    void reset(pointer p = pointer()) noexcept;
334    void reset(nullptr_t) noexcept;
335    template <class U> void reset(U) = delete;
336    void swap(unique_ptr& u) noexcept;
337};
338
339template <class T, class D>
340    void swap(unique_ptr<T, D>& x, unique_ptr<T, D>& y) noexcept;
341
342template <class T1, class D1, class T2, class D2>
343    bool operator==(const unique_ptr<T1, D1>& x, const unique_ptr<T2, D2>& y);
344template <class T1, class D1, class T2, class D2>
345    bool operator!=(const unique_ptr<T1, D1>& x, const unique_ptr<T2, D2>& y);
346template <class T1, class D1, class T2, class D2>
347    bool operator<(const unique_ptr<T1, D1>& x, const unique_ptr<T2, D2>& y);
348template <class T1, class D1, class T2, class D2>
349    bool operator<=(const unique_ptr<T1, D1>& x, const unique_ptr<T2, D2>& y);
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);
354
355template <class T, class D>
356    bool operator==(const unique_ptr<T, D>& x, nullptr_t) noexcept;
357template <class T, class D>
358    bool operator==(nullptr_t, const unique_ptr<T, D>& y) noexcept;
359template <class T, class D>
360    bool operator!=(const unique_ptr<T, D>& x, nullptr_t) noexcept;
361template <class T, class D>
362    bool operator!=(nullptr_t, const unique_ptr<T, D>& y) noexcept;
363
364template <class T, class D>
365    bool operator<(const unique_ptr<T, D>& x, nullptr_t);
366template <class T, class D>
367    bool operator<(nullptr_t, const unique_ptr<T, D>& y);
368template <class T, class D>
369    bool operator<=(const unique_ptr<T, D>& x, nullptr_t);
370template <class T, class D>
371    bool operator<=(nullptr_t, const unique_ptr<T, D>& y);
372template <class T, class D>
373    bool operator>(const unique_ptr<T, D>& x, nullptr_t);
374template <class T, class D>
375    bool operator>(nullptr_t, const unique_ptr<T, D>& y);
376template <class T, class D>
377    bool operator>=(const unique_ptr<T, D>& x, nullptr_t);
378template <class T, class D>
379    bool operator>=(nullptr_t, const unique_ptr<T, D>& y);
380
381class bad_weak_ptr
382    : public std::exception
383{
384    bad_weak_ptr() noexcept;
385};
386
387template<class T, class... Args> unique_ptr<T> make_unique(Args&&... args);     // C++14
388template<class T>                unique_ptr<T> make_unique(size_t n);           // C++14
389template<class T, class... Args> unspecified   make_unique(Args&&...) = delete; // C++14, T == U[N]
390
391template<class E, class T, class Y, class D>
392    basic_ostream<E, T>& operator<< (basic_ostream<E, T>& os, unique_ptr<Y, D> const& p);
393
394template<class T>
395class shared_ptr
396{
397public:
398    typedef T element_type;
399    typedef weak_ptr<T> weak_type; // C++17
400
401    // constructors:
402    constexpr shared_ptr() noexcept;
403    template<class Y> explicit shared_ptr(Y* p);
404    template<class Y, class D> shared_ptr(Y* p, D d);
405    template<class Y, class D, class A> shared_ptr(Y* p, D d, A a);
406    template <class D> shared_ptr(nullptr_t p, D d);
407    template <class D, class A> shared_ptr(nullptr_t p, D d, A a);
408    template<class Y> shared_ptr(const shared_ptr<Y>& r, T *p) noexcept;
409    shared_ptr(const shared_ptr& r) noexcept;
410    template<class Y> shared_ptr(const shared_ptr<Y>& r) noexcept;
411    shared_ptr(shared_ptr&& r) noexcept;
412    template<class Y> shared_ptr(shared_ptr<Y>&& r) noexcept;
413    template<class Y> explicit shared_ptr(const weak_ptr<Y>& r);
414    template<class Y> shared_ptr(auto_ptr<Y>&& r);          // removed in C++17
415    template <class Y, class D> shared_ptr(unique_ptr<Y, D>&& r);
416    shared_ptr(nullptr_t) : shared_ptr() { }
417
418    // destructor:
419    ~shared_ptr();
420
421    // assignment:
422    shared_ptr& operator=(const shared_ptr& r) noexcept;
423    template<class Y> shared_ptr& operator=(const shared_ptr<Y>& r) noexcept;
424    shared_ptr& operator=(shared_ptr&& r) noexcept;
425    template<class Y> shared_ptr& operator=(shared_ptr<Y>&& r);
426    template<class Y> shared_ptr& operator=(auto_ptr<Y>&& r); // removed in C++17
427    template <class Y, class D> shared_ptr& operator=(unique_ptr<Y, D>&& r);
428
429    // modifiers:
430    void swap(shared_ptr& r) noexcept;
431    void reset() noexcept;
432    template<class Y> void reset(Y* p);
433    template<class Y, class D> void reset(Y* p, D d);
434    template<class Y, class D, class A> void reset(Y* p, D d, A a);
435
436    // observers:
437    T* get() const noexcept;
438    T& operator*() const noexcept;
439    T* operator->() const noexcept;
440    long use_count() const noexcept;
441    bool unique() const noexcept;
442    explicit operator bool() const noexcept;
443    template<class U> bool owner_before(shared_ptr<U> const& b) const noexcept;
444    template<class U> bool owner_before(weak_ptr<U> const& b) const noexcept;
445};
446
447// shared_ptr comparisons:
448template<class T, class U>
449    bool operator==(shared_ptr<T> const& a, shared_ptr<U> const& b) noexcept;
450template<class T, class U>
451    bool operator!=(shared_ptr<T> const& a, shared_ptr<U> const& b) noexcept;
452template<class T, class U>
453    bool operator<(shared_ptr<T> const& a, shared_ptr<U> const& b) noexcept;
454template<class T, class U>
455    bool operator>(shared_ptr<T> const& a, shared_ptr<U> const& b) noexcept;
456template<class T, class U>
457    bool operator<=(shared_ptr<T> const& a, shared_ptr<U> const& b) noexcept;
458template<class T, class U>
459    bool operator>=(shared_ptr<T> const& a, shared_ptr<U> const& b) noexcept;
460
461template <class T>
462    bool operator==(const shared_ptr<T>& x, nullptr_t) noexcept;
463template <class T>
464    bool operator==(nullptr_t, const shared_ptr<T>& y) noexcept;
465template <class T>
466    bool operator!=(const shared_ptr<T>& x, nullptr_t) noexcept;
467template <class T>
468    bool operator!=(nullptr_t, const shared_ptr<T>& y) noexcept;
469template <class T>
470    bool operator<(const shared_ptr<T>& x, nullptr_t) noexcept;
471template <class T>
472bool operator<(nullptr_t, const shared_ptr<T>& y) noexcept;
473template <class T>
474    bool operator<=(const shared_ptr<T>& x, nullptr_t) noexcept;
475template <class T>
476    bool operator<=(nullptr_t, const shared_ptr<T>& y) noexcept;
477template <class T>
478    bool operator>(const shared_ptr<T>& x, nullptr_t) noexcept;
479template <class T>
480    bool operator>(nullptr_t, const shared_ptr<T>& y) noexcept;
481template <class T>
482    bool operator>=(const shared_ptr<T>& x, nullptr_t) noexcept;
483template <class T>
484    bool operator>=(nullptr_t, const shared_ptr<T>& y) noexcept;
485
486// shared_ptr specialized algorithms:
487template<class T> void swap(shared_ptr<T>& a, shared_ptr<T>& b) noexcept;
488
489// shared_ptr casts:
490template<class T, class U>
491    shared_ptr<T> static_pointer_cast(shared_ptr<U> const& r) noexcept;
492template<class T, class U>
493    shared_ptr<T> dynamic_pointer_cast(shared_ptr<U> const& r) noexcept;
494template<class T, class U>
495    shared_ptr<T> const_pointer_cast(shared_ptr<U> const& r) noexcept;
496
497// shared_ptr I/O:
498template<class E, class T, class Y>
499    basic_ostream<E, T>& operator<< (basic_ostream<E, T>& os, shared_ptr<Y> const& p);
500
501// shared_ptr get_deleter:
502template<class D, class T> D* get_deleter(shared_ptr<T> const& p) noexcept;
503
504template<class T, class... Args>
505    shared_ptr<T> make_shared(Args&&... args);
506template<class T, class A, class... Args>
507    shared_ptr<T> allocate_shared(const A& a, Args&&... args);
508
509template<class T>
510class weak_ptr
511{
512public:
513    typedef T element_type;
514
515    // constructors
516    constexpr weak_ptr() noexcept;
517    template<class Y> weak_ptr(shared_ptr<Y> const& r) noexcept;
518    weak_ptr(weak_ptr const& r) noexcept;
519    template<class Y> weak_ptr(weak_ptr<Y> const& r) noexcept;
520    weak_ptr(weak_ptr&& r) noexcept;                      // C++14
521    template<class Y> weak_ptr(weak_ptr<Y>&& r) noexcept; // C++14
522
523    // destructor
524    ~weak_ptr();
525
526    // assignment
527    weak_ptr& operator=(weak_ptr const& r) noexcept;
528    template<class Y> weak_ptr& operator=(weak_ptr<Y> const& r) noexcept;
529    template<class Y> weak_ptr& operator=(shared_ptr<Y> const& r) noexcept;
530    weak_ptr& operator=(weak_ptr&& r) noexcept;                      // C++14
531    template<class Y> weak_ptr& operator=(weak_ptr<Y>&& r) noexcept; // C++14
532
533    // modifiers
534    void swap(weak_ptr& r) noexcept;
535    void reset() noexcept;
536
537    // observers
538    long use_count() const noexcept;
539    bool expired() const noexcept;
540    shared_ptr<T> lock() const noexcept;
541    template<class U> bool owner_before(shared_ptr<U> const& b) const noexcept;
542    template<class U> bool owner_before(weak_ptr<U> const& b) const noexcept;
543};
544
545// weak_ptr specialized algorithms:
546template<class T> void swap(weak_ptr<T>& a, weak_ptr<T>& b) noexcept;
547
548// class owner_less:
549template<class T> struct owner_less;
550
551template<class T>
552struct owner_less<shared_ptr<T>>
553    : binary_function<shared_ptr<T>, shared_ptr<T>, bool>
554{
555    typedef bool result_type;
556    bool operator()(shared_ptr<T> const&, shared_ptr<T> const&) const noexcept;
557    bool operator()(shared_ptr<T> const&, weak_ptr<T> const&) const noexcept;
558    bool operator()(weak_ptr<T> const&, shared_ptr<T> const&) const noexcept;
559};
560
561template<class T>
562struct owner_less<weak_ptr<T>>
563    : binary_function<weak_ptr<T>, weak_ptr<T>, bool>
564{
565    typedef bool result_type;
566    bool operator()(weak_ptr<T> const&, weak_ptr<T> const&) const noexcept;
567    bool operator()(shared_ptr<T> const&, weak_ptr<T> const&) const noexcept;
568    bool operator()(weak_ptr<T> const&, shared_ptr<T> const&) const noexcept;
569};
570
571template <>  // Added in C++14
572struct owner_less<void>
573{
574    template <class _Tp, class _Up>
575    bool operator()( shared_ptr<_Tp> const& __x, shared_ptr<_Up> const& __y) const noexcept;
576    template <class _Tp, class _Up>
577    bool operator()( shared_ptr<_Tp> const& __x,   weak_ptr<_Up> const& __y) const noexcept;
578    template <class _Tp, class _Up>
579    bool operator()(   weak_ptr<_Tp> const& __x, shared_ptr<_Up> const& __y) const noexcept;
580    template <class _Tp, class _Up>
581    bool operator()(   weak_ptr<_Tp> const& __x,   weak_ptr<_Up> const& __y) const noexcept;
582
583    typedef void is_transparent;
584};
585
586template<class T>
587class enable_shared_from_this
588{
589protected:
590    constexpr enable_shared_from_this() noexcept;
591    enable_shared_from_this(enable_shared_from_this const&) noexcept;
592    enable_shared_from_this& operator=(enable_shared_from_this const&) noexcept;
593    ~enable_shared_from_this();
594public:
595    shared_ptr<T> shared_from_this();
596    shared_ptr<T const> shared_from_this() const;
597};
598
599template<class T>
600    bool atomic_is_lock_free(const shared_ptr<T>* p);
601template<class T>
602    shared_ptr<T> atomic_load(const shared_ptr<T>* p);
603template<class T>
604    shared_ptr<T> atomic_load_explicit(const shared_ptr<T>* p, memory_order mo);
605template<class T>
606    void atomic_store(shared_ptr<T>* p, shared_ptr<T> r);
607template<class T>
608    void atomic_store_explicit(shared_ptr<T>* p, shared_ptr<T> r, memory_order mo);
609template<class T>
610    shared_ptr<T> atomic_exchange(shared_ptr<T>* p, shared_ptr<T> r);
611template<class T>
612    shared_ptr<T>
613    atomic_exchange_explicit(shared_ptr<T>* p, shared_ptr<T> r, memory_order mo);
614template<class T>
615    bool
616    atomic_compare_exchange_weak(shared_ptr<T>* p, shared_ptr<T>* v, shared_ptr<T> w);
617template<class T>
618    bool
619    atomic_compare_exchange_strong( shared_ptr<T>* p, shared_ptr<T>* v, shared_ptr<T> w);
620template<class T>
621    bool
622    atomic_compare_exchange_weak_explicit(shared_ptr<T>* p, shared_ptr<T>* v,
623                                          shared_ptr<T> w, memory_order success,
624                                          memory_order failure);
625template<class T>
626    bool
627    atomic_compare_exchange_strong_explicit(shared_ptr<T>* p, shared_ptr<T>* v,
628                                            shared_ptr<T> w, memory_order success,
629                                            memory_order failure);
630// Hash support
631template <class T> struct hash;
632template <class T, class D> struct hash<unique_ptr<T, D> >;
633template <class T> struct hash<shared_ptr<T> >;
634
635template <class T, class Alloc>
636  inline constexpr bool uses_allocator_v = uses_allocator<T, Alloc>::value;
637
638// Pointer safety
639enum class pointer_safety { relaxed, preferred, strict };
640void declare_reachable(void *p);
641template <class T> T *undeclare_reachable(T *p);
642void declare_no_pointers(char *p, size_t n);
643void undeclare_no_pointers(char *p, size_t n);
644pointer_safety get_pointer_safety() noexcept;
645
646void* align(size_t alignment, size_t size, void*& ptr, size_t& space);
647
648}  // std
649
650*/
651
652#include <__config>
653#include <type_traits>
654#include <typeinfo>
655#include <cstddef>
656#include <cstdint>
657#include <new>
658#include <utility>
659#include <limits>
660#include <iterator>
661#include <__functional_base>
662#include <iosfwd>
663#include <tuple>
664#include <stdexcept>
665#include <cstring>
666#include <cassert>
667#if !defined(_LIBCPP_HAS_NO_ATOMIC_HEADER)
668#  include <atomic>
669#endif
670#include <version>
671
672#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
673#pragma GCC system_header
674#endif
675
676_LIBCPP_PUSH_MACROS
677#include <__undef_macros>
678
679
680_LIBCPP_BEGIN_NAMESPACE_STD
681
682template <class _ValueType>
683inline _LIBCPP_INLINE_VISIBILITY
684_ValueType __libcpp_relaxed_load(_ValueType const* __value) {
685#if !defined(_LIBCPP_HAS_NO_THREADS) && \
686    defined(__ATOMIC_RELAXED) &&        \
687    (__has_builtin(__atomic_load_n) || _GNUC_VER >= 407)
688    return __atomic_load_n(__value, __ATOMIC_RELAXED);
689#else
690    return *__value;
691#endif
692}
693
694template <class _ValueType>
695inline _LIBCPP_INLINE_VISIBILITY
696_ValueType __libcpp_acquire_load(_ValueType const* __value) {
697#if !defined(_LIBCPP_HAS_NO_THREADS) && \
698    defined(__ATOMIC_ACQUIRE) &&        \
699    (__has_builtin(__atomic_load_n) || _GNUC_VER >= 407)
700    return __atomic_load_n(__value, __ATOMIC_ACQUIRE);
701#else
702    return *__value;
703#endif
704}
705
706// addressof moved to <type_traits>
707
708template <class _Tp> class allocator;
709
710template <>
711class _LIBCPP_TEMPLATE_VIS allocator<void>
712{
713public:
714    typedef void*             pointer;
715    typedef const void*       const_pointer;
716    typedef void              value_type;
717
718    template <class _Up> struct rebind {typedef allocator<_Up> other;};
719};
720
721template <>
722class _LIBCPP_TEMPLATE_VIS allocator<const void>
723{
724public:
725    typedef const void*       pointer;
726    typedef const void*       const_pointer;
727    typedef const void        value_type;
728
729    template <class _Up> struct rebind {typedef allocator<_Up> other;};
730};
731
732// pointer_traits
733
734template <class _Tp, class = void>
735struct __has_element_type : false_type {};
736
737template <class _Tp>
738struct __has_element_type<_Tp,
739              typename __void_t<typename _Tp::element_type>::type> : true_type {};
740
741template <class _Ptr, bool = __has_element_type<_Ptr>::value>
742struct __pointer_traits_element_type;
743
744template <class _Ptr>
745struct __pointer_traits_element_type<_Ptr, true>
746{
747    typedef typename _Ptr::element_type type;
748};
749
750#ifndef _LIBCPP_HAS_NO_VARIADICS
751
752template <template <class, class...> class _Sp, class _Tp, class ..._Args>
753struct __pointer_traits_element_type<_Sp<_Tp, _Args...>, true>
754{
755    typedef typename _Sp<_Tp, _Args...>::element_type type;
756};
757
758template <template <class, class...> class _Sp, class _Tp, class ..._Args>
759struct __pointer_traits_element_type<_Sp<_Tp, _Args...>, false>
760{
761    typedef _Tp type;
762};
763
764#else  // _LIBCPP_HAS_NO_VARIADICS
765
766template <template <class> class _Sp, class _Tp>
767struct __pointer_traits_element_type<_Sp<_Tp>, true>
768{
769    typedef typename _Sp<_Tp>::element_type type;
770};
771
772template <template <class> class _Sp, class _Tp>
773struct __pointer_traits_element_type<_Sp<_Tp>, false>
774{
775    typedef _Tp type;
776};
777
778template <template <class, class> class _Sp, class _Tp, class _A0>
779struct __pointer_traits_element_type<_Sp<_Tp, _A0>, true>
780{
781    typedef typename _Sp<_Tp, _A0>::element_type type;
782};
783
784template <template <class, class> class _Sp, class _Tp, class _A0>
785struct __pointer_traits_element_type<_Sp<_Tp, _A0>, false>
786{
787    typedef _Tp type;
788};
789
790template <template <class, class, class> class _Sp, class _Tp, class _A0, class _A1>
791struct __pointer_traits_element_type<_Sp<_Tp, _A0, _A1>, true>
792{
793    typedef typename _Sp<_Tp, _A0, _A1>::element_type type;
794};
795
796template <template <class, class, class> class _Sp, class _Tp, class _A0, class _A1>
797struct __pointer_traits_element_type<_Sp<_Tp, _A0, _A1>, false>
798{
799    typedef _Tp type;
800};
801
802template <template <class, class, class, class> class _Sp, class _Tp, class _A0,
803                                                           class _A1, class _A2>
804struct __pointer_traits_element_type<_Sp<_Tp, _A0, _A1, _A2>, true>
805{
806    typedef typename _Sp<_Tp, _A0, _A1, _A2>::element_type type;
807};
808
809template <template <class, class, class, class> class _Sp, class _Tp, class _A0,
810                                                           class _A1, class _A2>
811struct __pointer_traits_element_type<_Sp<_Tp, _A0, _A1, _A2>, false>
812{
813    typedef _Tp type;
814};
815
816#endif  // _LIBCPP_HAS_NO_VARIADICS
817
818template <class _Tp, class = void>
819struct __has_difference_type : false_type {};
820
821template <class _Tp>
822struct __has_difference_type<_Tp,
823            typename __void_t<typename _Tp::difference_type>::type> : true_type {};
824
825template <class _Ptr, bool = __has_difference_type<_Ptr>::value>
826struct __pointer_traits_difference_type
827{
828    typedef ptrdiff_t type;
829};
830
831template <class _Ptr>
832struct __pointer_traits_difference_type<_Ptr, true>
833{
834    typedef typename _Ptr::difference_type type;
835};
836
837template <class _Tp, class _Up>
838struct __has_rebind
839{
840private:
841    struct __two {char __lx; char __lxx;};
842    template <class _Xp> static __two __test(...);
843    template <class _Xp> static char __test(typename _Xp::template rebind<_Up>* = 0);
844public:
845    static const bool value = sizeof(__test<_Tp>(0)) == 1;
846};
847
848template <class _Tp, class _Up, bool = __has_rebind<_Tp, _Up>::value>
849struct __pointer_traits_rebind
850{
851#ifndef _LIBCPP_CXX03_LANG
852    typedef typename _Tp::template rebind<_Up> type;
853#else
854    typedef typename _Tp::template rebind<_Up>::other type;
855#endif
856};
857
858#ifndef _LIBCPP_HAS_NO_VARIADICS
859
860template <template <class, class...> class _Sp, class _Tp, class ..._Args, class _Up>
861struct __pointer_traits_rebind<_Sp<_Tp, _Args...>, _Up, true>
862{
863#ifndef _LIBCPP_CXX03_LANG
864    typedef typename _Sp<_Tp, _Args...>::template rebind<_Up> type;
865#else
866    typedef typename _Sp<_Tp, _Args...>::template rebind<_Up>::other type;
867#endif
868};
869
870template <template <class, class...> class _Sp, class _Tp, class ..._Args, class _Up>
871struct __pointer_traits_rebind<_Sp<_Tp, _Args...>, _Up, false>
872{
873    typedef _Sp<_Up, _Args...> type;
874};
875
876#else  // _LIBCPP_HAS_NO_VARIADICS
877
878template <template <class> class _Sp, class _Tp, class _Up>
879struct __pointer_traits_rebind<_Sp<_Tp>, _Up, true>
880{
881#ifndef _LIBCPP_CXX03_LANG
882    typedef typename _Sp<_Tp>::template rebind<_Up> type;
883#else
884    typedef typename _Sp<_Tp>::template rebind<_Up>::other type;
885#endif
886};
887
888template <template <class> class _Sp, class _Tp, class _Up>
889struct __pointer_traits_rebind<_Sp<_Tp>, _Up, false>
890{
891    typedef _Sp<_Up> type;
892};
893
894template <template <class, class> class _Sp, class _Tp, class _A0, class _Up>
895struct __pointer_traits_rebind<_Sp<_Tp, _A0>, _Up, true>
896{
897#ifndef _LIBCPP_CXX03_LANG
898    typedef typename _Sp<_Tp, _A0>::template rebind<_Up> type;
899#else
900    typedef typename _Sp<_Tp, _A0>::template rebind<_Up>::other type;
901#endif
902};
903
904template <template <class, class> class _Sp, class _Tp, class _A0, class _Up>
905struct __pointer_traits_rebind<_Sp<_Tp, _A0>, _Up, false>
906{
907    typedef _Sp<_Up, _A0> type;
908};
909
910template <template <class, class, class> class _Sp, class _Tp, class _A0,
911                                         class _A1, class _Up>
912struct __pointer_traits_rebind<_Sp<_Tp, _A0, _A1>, _Up, true>
913{
914#ifndef _LIBCPP_CXX03_LANG
915    typedef typename _Sp<_Tp, _A0, _A1>::template rebind<_Up> type;
916#else
917    typedef typename _Sp<_Tp, _A0, _A1>::template rebind<_Up>::other type;
918#endif
919};
920
921template <template <class, class, class> class _Sp, class _Tp, class _A0,
922                                         class _A1, class _Up>
923struct __pointer_traits_rebind<_Sp<_Tp, _A0, _A1>, _Up, false>
924{
925    typedef _Sp<_Up, _A0, _A1> type;
926};
927
928template <template <class, class, class, class> class _Sp, class _Tp, class _A0,
929                                                class _A1, class _A2, class _Up>
930struct __pointer_traits_rebind<_Sp<_Tp, _A0, _A1, _A2>, _Up, true>
931{
932#ifndef _LIBCPP_CXX03_LANG
933    typedef typename _Sp<_Tp, _A0, _A1, _A2>::template rebind<_Up> type;
934#else
935    typedef typename _Sp<_Tp, _A0, _A1, _A2>::template rebind<_Up>::other type;
936#endif
937};
938
939template <template <class, class, class, class> class _Sp, class _Tp, class _A0,
940                                                class _A1, class _A2, class _Up>
941struct __pointer_traits_rebind<_Sp<_Tp, _A0, _A1, _A2>, _Up, false>
942{
943    typedef _Sp<_Up, _A0, _A1, _A2> type;
944};
945
946#endif  // _LIBCPP_HAS_NO_VARIADICS
947
948template <class _Ptr>
949struct _LIBCPP_TEMPLATE_VIS pointer_traits
950{
951    typedef _Ptr                                                     pointer;
952    typedef typename __pointer_traits_element_type<pointer>::type    element_type;
953    typedef typename __pointer_traits_difference_type<pointer>::type difference_type;
954
955#ifndef _LIBCPP_CXX03_LANG
956    template <class _Up> using rebind = typename __pointer_traits_rebind<pointer, _Up>::type;
957#else
958    template <class _Up> struct rebind
959        {typedef typename __pointer_traits_rebind<pointer, _Up>::type other;};
960#endif  // _LIBCPP_CXX03_LANG
961
962private:
963    struct __nat {};
964public:
965    _LIBCPP_INLINE_VISIBILITY
966    static pointer pointer_to(typename conditional<is_void<element_type>::value,
967                                           __nat, element_type>::type& __r)
968        {return pointer::pointer_to(__r);}
969};
970
971template <class _Tp>
972struct _LIBCPP_TEMPLATE_VIS pointer_traits<_Tp*>
973{
974    typedef _Tp*      pointer;
975    typedef _Tp       element_type;
976    typedef ptrdiff_t difference_type;
977
978#ifndef _LIBCPP_CXX03_LANG
979    template <class _Up> using rebind = _Up*;
980#else
981    template <class _Up> struct rebind {typedef _Up* other;};
982#endif
983
984private:
985    struct __nat {};
986public:
987    _LIBCPP_INLINE_VISIBILITY
988    static pointer pointer_to(typename conditional<is_void<element_type>::value,
989                                      __nat, element_type>::type& __r) _NOEXCEPT
990        {return _VSTD::addressof(__r);}
991};
992
993template <class _From, class _To>
994struct __rebind_pointer {
995#ifndef _LIBCPP_CXX03_LANG
996    typedef typename pointer_traits<_From>::template rebind<_To>        type;
997#else
998    typedef typename pointer_traits<_From>::template rebind<_To>::other type;
999#endif
1000};
1001
1002// allocator_traits
1003
1004template <class _Tp, class = void>
1005struct __has_pointer_type : false_type {};
1006
1007template <class _Tp>
1008struct __has_pointer_type<_Tp,
1009          typename __void_t<typename _Tp::pointer>::type> : true_type {};
1010
1011namespace __pointer_type_imp
1012{
1013
1014template <class _Tp, class _Dp, bool = __has_pointer_type<_Dp>::value>
1015struct __pointer_type
1016{
1017    typedef typename _Dp::pointer type;
1018};
1019
1020template <class _Tp, class _Dp>
1021struct __pointer_type<_Tp, _Dp, false>
1022{
1023    typedef _Tp* type;
1024};
1025
1026}  // __pointer_type_imp
1027
1028template <class _Tp, class _Dp>
1029struct __pointer_type
1030{
1031    typedef typename __pointer_type_imp::__pointer_type<_Tp, typename remove_reference<_Dp>::type>::type type;
1032};
1033
1034template <class _Tp, class = void>
1035struct __has_const_pointer : false_type {};
1036
1037template <class _Tp>
1038struct __has_const_pointer<_Tp,
1039            typename __void_t<typename _Tp::const_pointer>::type> : true_type {};
1040
1041template <class _Tp, class _Ptr, class _Alloc, bool = __has_const_pointer<_Alloc>::value>
1042struct __const_pointer
1043{
1044    typedef typename _Alloc::const_pointer type;
1045};
1046
1047template <class _Tp, class _Ptr, class _Alloc>
1048struct __const_pointer<_Tp, _Ptr, _Alloc, false>
1049{
1050#ifndef _LIBCPP_CXX03_LANG
1051    typedef typename pointer_traits<_Ptr>::template rebind<const _Tp> type;
1052#else
1053    typedef typename pointer_traits<_Ptr>::template rebind<const _Tp>::other type;
1054#endif
1055};
1056
1057template <class _Tp, class = void>
1058struct __has_void_pointer : false_type {};
1059
1060template <class _Tp>
1061struct __has_void_pointer<_Tp,
1062               typename __void_t<typename _Tp::void_pointer>::type> : true_type {};
1063
1064template <class _Ptr, class _Alloc, bool = __has_void_pointer<_Alloc>::value>
1065struct __void_pointer
1066{
1067    typedef typename _Alloc::void_pointer type;
1068};
1069
1070template <class _Ptr, class _Alloc>
1071struct __void_pointer<_Ptr, _Alloc, false>
1072{
1073#ifndef _LIBCPP_CXX03_LANG
1074    typedef typename pointer_traits<_Ptr>::template rebind<void> type;
1075#else
1076    typedef typename pointer_traits<_Ptr>::template rebind<void>::other type;
1077#endif
1078};
1079
1080template <class _Tp, class = void>
1081struct __has_const_void_pointer : false_type {};
1082
1083template <class _Tp>
1084struct __has_const_void_pointer<_Tp,
1085            typename __void_t<typename _Tp::const_void_pointer>::type> : true_type {};
1086
1087template <class _Ptr, class _Alloc, bool = __has_const_void_pointer<_Alloc>::value>
1088struct __const_void_pointer
1089{
1090    typedef typename _Alloc::const_void_pointer type;
1091};
1092
1093template <class _Ptr, class _Alloc>
1094struct __const_void_pointer<_Ptr, _Alloc, false>
1095{
1096#ifndef _LIBCPP_CXX03_LANG
1097    typedef typename pointer_traits<_Ptr>::template rebind<const void> type;
1098#else
1099    typedef typename pointer_traits<_Ptr>::template rebind<const void>::other type;
1100#endif
1101};
1102
1103template <class _Tp>
1104inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR
1105_Tp*
1106__to_raw_pointer(_Tp* __p) _NOEXCEPT
1107{
1108    return __p;
1109}
1110
1111#if _LIBCPP_STD_VER <= 17
1112template <class _Pointer>
1113inline _LIBCPP_INLINE_VISIBILITY
1114typename pointer_traits<_Pointer>::element_type*
1115__to_raw_pointer(_Pointer __p) _NOEXCEPT
1116{
1117    return _VSTD::__to_raw_pointer(__p.operator->());
1118}
1119#else
1120template <class _Pointer>
1121inline _LIBCPP_INLINE_VISIBILITY
1122auto
1123__to_raw_pointer(const _Pointer& __p) _NOEXCEPT
1124-> decltype(pointer_traits<_Pointer>::to_address(__p))
1125{
1126    return pointer_traits<_Pointer>::to_address(__p);
1127}
1128
1129template <class _Pointer, class... _None>
1130inline _LIBCPP_INLINE_VISIBILITY
1131auto
1132__to_raw_pointer(const _Pointer& __p, _None...) _NOEXCEPT
1133{
1134    return _VSTD::__to_raw_pointer(__p.operator->());
1135}
1136
1137template <class _Tp>
1138inline _LIBCPP_INLINE_VISIBILITY constexpr
1139_Tp*
1140to_address(_Tp* __p) _NOEXCEPT
1141{
1142    static_assert(!is_function_v<_Tp>, "_Tp is a function type");
1143    return __p;
1144}
1145
1146template <class _Pointer>
1147inline _LIBCPP_INLINE_VISIBILITY
1148auto
1149to_address(const _Pointer& __p) _NOEXCEPT
1150{
1151    return _VSTD::__to_raw_pointer(__p);
1152}
1153#endif
1154
1155template <class _Tp, class = void>
1156struct __has_size_type : false_type {};
1157
1158template <class _Tp>
1159struct __has_size_type<_Tp,
1160               typename __void_t<typename _Tp::size_type>::type> : true_type {};
1161
1162template <class _Alloc, class _DiffType, bool = __has_size_type<_Alloc>::value>
1163struct __size_type
1164{
1165    typedef typename make_unsigned<_DiffType>::type type;
1166};
1167
1168template <class _Alloc, class _DiffType>
1169struct __size_type<_Alloc, _DiffType, true>
1170{
1171    typedef typename _Alloc::size_type type;
1172};
1173
1174template <class _Tp, class = void>
1175struct __has_propagate_on_container_copy_assignment : false_type {};
1176
1177template <class _Tp>
1178struct __has_propagate_on_container_copy_assignment<_Tp,
1179    typename __void_t<typename _Tp::propagate_on_container_copy_assignment>::type>
1180        : true_type {};
1181
1182template <class _Alloc, bool = __has_propagate_on_container_copy_assignment<_Alloc>::value>
1183struct __propagate_on_container_copy_assignment
1184{
1185    typedef false_type type;
1186};
1187
1188template <class _Alloc>
1189struct __propagate_on_container_copy_assignment<_Alloc, true>
1190{
1191    typedef typename _Alloc::propagate_on_container_copy_assignment type;
1192};
1193
1194template <class _Tp, class = void>
1195struct __has_propagate_on_container_move_assignment : false_type {};
1196
1197template <class _Tp>
1198struct __has_propagate_on_container_move_assignment<_Tp,
1199           typename __void_t<typename _Tp::propagate_on_container_move_assignment>::type>
1200               : true_type {};
1201
1202template <class _Alloc, bool = __has_propagate_on_container_move_assignment<_Alloc>::value>
1203struct __propagate_on_container_move_assignment
1204{
1205    typedef false_type type;
1206};
1207
1208template <class _Alloc>
1209struct __propagate_on_container_move_assignment<_Alloc, true>
1210{
1211    typedef typename _Alloc::propagate_on_container_move_assignment type;
1212};
1213
1214template <class _Tp, class = void>
1215struct __has_propagate_on_container_swap : false_type {};
1216
1217template <class _Tp>
1218struct __has_propagate_on_container_swap<_Tp,
1219           typename __void_t<typename _Tp::propagate_on_container_swap>::type>
1220               : true_type {};
1221
1222template <class _Alloc, bool = __has_propagate_on_container_swap<_Alloc>::value>
1223struct __propagate_on_container_swap
1224{
1225    typedef false_type type;
1226};
1227
1228template <class _Alloc>
1229struct __propagate_on_container_swap<_Alloc, true>
1230{
1231    typedef typename _Alloc::propagate_on_container_swap type;
1232};
1233
1234template <class _Tp, class = void>
1235struct __has_is_always_equal : false_type {};
1236
1237template <class _Tp>
1238struct __has_is_always_equal<_Tp,
1239           typename __void_t<typename _Tp::is_always_equal>::type>
1240               : true_type {};
1241
1242template <class _Alloc, bool = __has_is_always_equal<_Alloc>::value>
1243struct __is_always_equal
1244{
1245    typedef typename _VSTD::is_empty<_Alloc>::type type;
1246};
1247
1248template <class _Alloc>
1249struct __is_always_equal<_Alloc, true>
1250{
1251    typedef typename _Alloc::is_always_equal type;
1252};
1253
1254template <class _Tp, class _Up, bool = __has_rebind<_Tp, _Up>::value>
1255struct __has_rebind_other
1256{
1257private:
1258    struct __two {char __lx; char __lxx;};
1259    template <class _Xp> static __two __test(...);
1260    template <class _Xp> static char __test(typename _Xp::template rebind<_Up>::other* = 0);
1261public:
1262    static const bool value = sizeof(__test<_Tp>(0)) == 1;
1263};
1264
1265template <class _Tp, class _Up>
1266struct __has_rebind_other<_Tp, _Up, false>
1267{
1268    static const bool value = false;
1269};
1270
1271template <class _Tp, class _Up, bool = __has_rebind_other<_Tp, _Up>::value>
1272struct __allocator_traits_rebind
1273{
1274    typedef typename _Tp::template rebind<_Up>::other type;
1275};
1276
1277#ifndef _LIBCPP_HAS_NO_VARIADICS
1278
1279template <template <class, class...> class _Alloc, class _Tp, class ..._Args, class _Up>
1280struct __allocator_traits_rebind<_Alloc<_Tp, _Args...>, _Up, true>
1281{
1282    typedef typename _Alloc<_Tp, _Args...>::template rebind<_Up>::other type;
1283};
1284
1285template <template <class, class...> class _Alloc, class _Tp, class ..._Args, class _Up>
1286struct __allocator_traits_rebind<_Alloc<_Tp, _Args...>, _Up, false>
1287{
1288    typedef _Alloc<_Up, _Args...> type;
1289};
1290
1291#else  // _LIBCPP_HAS_NO_VARIADICS
1292
1293template <template <class> class _Alloc, class _Tp, class _Up>
1294struct __allocator_traits_rebind<_Alloc<_Tp>, _Up, true>
1295{
1296    typedef typename _Alloc<_Tp>::template rebind<_Up>::other type;
1297};
1298
1299template <template <class> class _Alloc, class _Tp, class _Up>
1300struct __allocator_traits_rebind<_Alloc<_Tp>, _Up, false>
1301{
1302    typedef _Alloc<_Up> type;
1303};
1304
1305template <template <class, class> class _Alloc, class _Tp, class _A0, class _Up>
1306struct __allocator_traits_rebind<_Alloc<_Tp, _A0>, _Up, true>
1307{
1308    typedef typename _Alloc<_Tp, _A0>::template rebind<_Up>::other type;
1309};
1310
1311template <template <class, class> class _Alloc, class _Tp, class _A0, class _Up>
1312struct __allocator_traits_rebind<_Alloc<_Tp, _A0>, _Up, false>
1313{
1314    typedef _Alloc<_Up, _A0> type;
1315};
1316
1317template <template <class, class, class> class _Alloc, class _Tp, class _A0,
1318                                         class _A1, class _Up>
1319struct __allocator_traits_rebind<_Alloc<_Tp, _A0, _A1>, _Up, true>
1320{
1321    typedef typename _Alloc<_Tp, _A0, _A1>::template rebind<_Up>::other type;
1322};
1323
1324template <template <class, class, class> class _Alloc, class _Tp, class _A0,
1325                                         class _A1, class _Up>
1326struct __allocator_traits_rebind<_Alloc<_Tp, _A0, _A1>, _Up, false>
1327{
1328    typedef _Alloc<_Up, _A0, _A1> type;
1329};
1330
1331template <template <class, class, class, class> class _Alloc, class _Tp, class _A0,
1332                                                class _A1, class _A2, class _Up>
1333struct __allocator_traits_rebind<_Alloc<_Tp, _A0, _A1, _A2>, _Up, true>
1334{
1335    typedef typename _Alloc<_Tp, _A0, _A1, _A2>::template rebind<_Up>::other type;
1336};
1337
1338template <template <class, class, class, class> class _Alloc, class _Tp, class _A0,
1339                                                class _A1, class _A2, class _Up>
1340struct __allocator_traits_rebind<_Alloc<_Tp, _A0, _A1, _A2>, _Up, false>
1341{
1342    typedef _Alloc<_Up, _A0, _A1, _A2> type;
1343};
1344
1345#endif  // _LIBCPP_HAS_NO_VARIADICS
1346
1347#ifndef _LIBCPP_CXX03_LANG
1348
1349template <class _Alloc, class _SizeType, class _ConstVoidPtr>
1350auto
1351__has_allocate_hint_test(_Alloc&& __a, _SizeType&& __sz, _ConstVoidPtr&& __p)
1352    -> decltype((void)__a.allocate(__sz, __p), true_type());
1353
1354template <class _Alloc, class _SizeType, class _ConstVoidPtr>
1355auto
1356__has_allocate_hint_test(const _Alloc& __a, _SizeType&& __sz, _ConstVoidPtr&& __p)
1357    -> false_type;
1358
1359template <class _Alloc, class _SizeType, class _ConstVoidPtr>
1360struct __has_allocate_hint
1361    : integral_constant<bool,
1362        is_same<
1363            decltype(_VSTD::__has_allocate_hint_test(declval<_Alloc>(),
1364                                          declval<_SizeType>(),
1365                                          declval<_ConstVoidPtr>())),
1366            true_type>::value>
1367{
1368};
1369
1370#else  // _LIBCPP_CXX03_LANG
1371
1372template <class _Alloc, class _SizeType, class _ConstVoidPtr>
1373struct __has_allocate_hint
1374    : true_type
1375{
1376};
1377
1378#endif  // _LIBCPP_CXX03_LANG
1379
1380#if !defined(_LIBCPP_CXX03_LANG)
1381
1382template <class _Alloc, class _Tp, class ..._Args>
1383decltype(_VSTD::declval<_Alloc>().construct(_VSTD::declval<_Tp*>(),
1384                                           _VSTD::declval<_Args>()...),
1385                                           true_type())
1386__has_construct_test(_Alloc&& __a, _Tp* __p, _Args&& ...__args);
1387
1388template <class _Alloc, class _Pointer, class ..._Args>
1389false_type
1390__has_construct_test(const _Alloc& __a, _Pointer&& __p, _Args&& ...__args);
1391
1392template <class _Alloc, class _Pointer, class ..._Args>
1393struct __has_construct
1394    : integral_constant<bool,
1395        is_same<
1396            decltype(_VSTD::__has_construct_test(declval<_Alloc>(),
1397                                          declval<_Pointer>(),
1398                                          declval<_Args>()...)),
1399            true_type>::value>
1400{
1401};
1402
1403template <class _Alloc, class _Pointer>
1404auto
1405__has_destroy_test(_Alloc&& __a, _Pointer&& __p)
1406    -> decltype(__a.destroy(__p), true_type());
1407
1408template <class _Alloc, class _Pointer>
1409auto
1410__has_destroy_test(const _Alloc& __a, _Pointer&& __p)
1411    -> false_type;
1412
1413template <class _Alloc, class _Pointer>
1414struct __has_destroy
1415    : integral_constant<bool,
1416        is_same<
1417            decltype(_VSTD::__has_destroy_test(declval<_Alloc>(),
1418                                        declval<_Pointer>())),
1419            true_type>::value>
1420{
1421};
1422
1423template <class _Alloc>
1424auto
1425__has_max_size_test(_Alloc&& __a)
1426    -> decltype(__a.max_size(), true_type());
1427
1428template <class _Alloc>
1429auto
1430__has_max_size_test(const volatile _Alloc& __a)
1431    -> false_type;
1432
1433template <class _Alloc>
1434struct __has_max_size
1435    : integral_constant<bool,
1436        is_same<
1437            decltype(_VSTD::__has_max_size_test(declval<_Alloc&>())),
1438            true_type>::value>
1439{
1440};
1441
1442template <class _Alloc>
1443auto
1444__has_select_on_container_copy_construction_test(_Alloc&& __a)
1445    -> decltype(__a.select_on_container_copy_construction(), true_type());
1446
1447template <class _Alloc>
1448auto
1449__has_select_on_container_copy_construction_test(const volatile _Alloc& __a)
1450    -> false_type;
1451
1452template <class _Alloc>
1453struct __has_select_on_container_copy_construction
1454    : integral_constant<bool,
1455        is_same<
1456            decltype(_VSTD::__has_select_on_container_copy_construction_test(declval<_Alloc&>())),
1457            true_type>::value>
1458{
1459};
1460
1461#else  // _LIBCPP_CXX03_LANG
1462
1463#ifndef _LIBCPP_HAS_NO_VARIADICS
1464
1465template <class _Alloc, class _Pointer, class ..._Args>
1466struct __has_construct
1467    : false_type
1468{
1469};
1470
1471#else  // _LIBCPP_HAS_NO_VARIADICS
1472
1473template <class _Alloc, class _Pointer, class _Args>
1474struct __has_construct
1475    : false_type
1476{
1477};
1478
1479#endif  // _LIBCPP_HAS_NO_VARIADICS
1480
1481template <class _Alloc, class _Pointer>
1482struct __has_destroy
1483    : false_type
1484{
1485};
1486
1487template <class _Alloc>
1488struct __has_max_size
1489    : true_type
1490{
1491};
1492
1493template <class _Alloc>
1494struct __has_select_on_container_copy_construction
1495    : false_type
1496{
1497};
1498
1499#endif  // _LIBCPP_CXX03_LANG
1500
1501template <class _Alloc, class _Ptr, bool = __has_difference_type<_Alloc>::value>
1502struct __alloc_traits_difference_type
1503{
1504    typedef typename pointer_traits<_Ptr>::difference_type type;
1505};
1506
1507template <class _Alloc, class _Ptr>
1508struct __alloc_traits_difference_type<_Alloc, _Ptr, true>
1509{
1510    typedef typename _Alloc::difference_type type;
1511};
1512
1513template <class _Alloc>
1514struct _LIBCPP_TEMPLATE_VIS allocator_traits
1515{
1516    typedef _Alloc                              allocator_type;
1517    typedef typename allocator_type::value_type value_type;
1518
1519    typedef typename __pointer_type<value_type, allocator_type>::type pointer;
1520    typedef typename __const_pointer<value_type, pointer, allocator_type>::type const_pointer;
1521    typedef typename __void_pointer<pointer, allocator_type>::type void_pointer;
1522    typedef typename __const_void_pointer<pointer, allocator_type>::type const_void_pointer;
1523
1524    typedef typename __alloc_traits_difference_type<allocator_type, pointer>::type difference_type;
1525    typedef typename __size_type<allocator_type, difference_type>::type size_type;
1526
1527    typedef typename __propagate_on_container_copy_assignment<allocator_type>::type
1528                     propagate_on_container_copy_assignment;
1529    typedef typename __propagate_on_container_move_assignment<allocator_type>::type
1530                     propagate_on_container_move_assignment;
1531    typedef typename __propagate_on_container_swap<allocator_type>::type
1532                     propagate_on_container_swap;
1533    typedef typename __is_always_equal<allocator_type>::type
1534                     is_always_equal;
1535
1536#ifndef _LIBCPP_CXX03_LANG
1537    template <class _Tp> using rebind_alloc =
1538                  typename __allocator_traits_rebind<allocator_type, _Tp>::type;
1539    template <class _Tp> using rebind_traits = allocator_traits<rebind_alloc<_Tp>>;
1540#else  // _LIBCPP_CXX03_LANG
1541    template <class _Tp> struct rebind_alloc
1542        {typedef typename __allocator_traits_rebind<allocator_type, _Tp>::type other;};
1543    template <class _Tp> struct rebind_traits
1544        {typedef allocator_traits<typename rebind_alloc<_Tp>::other> other;};
1545#endif  // _LIBCPP_CXX03_LANG
1546
1547    _LIBCPP_NODISCARD_AFTER_CXX17 _LIBCPP_INLINE_VISIBILITY
1548    static pointer allocate(allocator_type& __a, size_type __n)
1549        {return __a.allocate(__n);}
1550    _LIBCPP_NODISCARD_AFTER_CXX17 _LIBCPP_INLINE_VISIBILITY
1551    static pointer allocate(allocator_type& __a, size_type __n, const_void_pointer __hint)
1552        {return __allocate(__a, __n, __hint,
1553            __has_allocate_hint<allocator_type, size_type, const_void_pointer>());}
1554
1555    _LIBCPP_INLINE_VISIBILITY
1556    static void deallocate(allocator_type& __a, pointer __p, size_type __n) _NOEXCEPT
1557        {__a.deallocate(__p, __n);}
1558
1559#ifndef _LIBCPP_HAS_NO_VARIADICS
1560    template <class _Tp, class... _Args>
1561        _LIBCPP_INLINE_VISIBILITY
1562        static void construct(allocator_type& __a, _Tp* __p, _Args&&... __args)
1563            {__construct(__has_construct<allocator_type, _Tp*, _Args...>(),
1564                         __a, __p, _VSTD::forward<_Args>(__args)...);}
1565#else  // _LIBCPP_HAS_NO_VARIADICS
1566    template <class _Tp>
1567        _LIBCPP_INLINE_VISIBILITY
1568        static void construct(allocator_type&, _Tp* __p)
1569            {
1570                ::new ((void*)__p) _Tp();
1571            }
1572    template <class _Tp, class _A0>
1573        _LIBCPP_INLINE_VISIBILITY
1574        static void construct(allocator_type&, _Tp* __p, const _A0& __a0)
1575            {
1576                ::new ((void*)__p) _Tp(__a0);
1577            }
1578    template <class _Tp, class _A0, class _A1>
1579        _LIBCPP_INLINE_VISIBILITY
1580        static void construct(allocator_type&, _Tp* __p, const _A0& __a0,
1581                              const _A1& __a1)
1582            {
1583                ::new ((void*)__p) _Tp(__a0, __a1);
1584            }
1585    template <class _Tp, class _A0, class _A1, class _A2>
1586        _LIBCPP_INLINE_VISIBILITY
1587        static void construct(allocator_type&, _Tp* __p, const _A0& __a0,
1588                              const _A1& __a1, const _A2& __a2)
1589            {
1590                ::new ((void*)__p) _Tp(__a0, __a1, __a2);
1591            }
1592#endif  // _LIBCPP_HAS_NO_VARIADICS
1593
1594    template <class _Tp>
1595        _LIBCPP_INLINE_VISIBILITY
1596        static void destroy(allocator_type& __a, _Tp* __p)
1597            {__destroy(__has_destroy<allocator_type, _Tp*>(), __a, __p);}
1598
1599    _LIBCPP_INLINE_VISIBILITY
1600    static size_type max_size(const allocator_type& __a) _NOEXCEPT
1601        {return __max_size(__has_max_size<const allocator_type>(), __a);}
1602
1603    _LIBCPP_INLINE_VISIBILITY
1604    static allocator_type
1605        select_on_container_copy_construction(const allocator_type& __a)
1606            {return __select_on_container_copy_construction(
1607                __has_select_on_container_copy_construction<const allocator_type>(),
1608                __a);}
1609
1610    template <class _Ptr>
1611        _LIBCPP_INLINE_VISIBILITY
1612        static
1613        void
1614        __construct_forward(allocator_type& __a, _Ptr __begin1, _Ptr __end1, _Ptr& __begin2)
1615        {
1616            for (; __begin1 != __end1; ++__begin1, ++__begin2)
1617                construct(__a, _VSTD::__to_raw_pointer(__begin2), _VSTD::move_if_noexcept(*__begin1));
1618        }
1619
1620    template <class _Tp>
1621        _LIBCPP_INLINE_VISIBILITY
1622        static
1623        typename enable_if
1624        <
1625            (is_same<allocator_type, allocator<_Tp> >::value
1626                || !__has_construct<allocator_type, _Tp*, _Tp>::value) &&
1627             is_trivially_move_constructible<_Tp>::value,
1628            void
1629        >::type
1630        __construct_forward(allocator_type&, _Tp* __begin1, _Tp* __end1, _Tp*& __begin2)
1631        {
1632            ptrdiff_t _Np = __end1 - __begin1;
1633            if (_Np > 0)
1634            {
1635                _VSTD::memcpy(__begin2, __begin1, _Np * sizeof(_Tp));
1636                __begin2 += _Np;
1637            }
1638        }
1639
1640    template <class _Iter, class _Ptr>
1641        _LIBCPP_INLINE_VISIBILITY
1642        static
1643        void
1644        __construct_range_forward(allocator_type& __a, _Iter __begin1, _Iter __end1, _Ptr& __begin2)
1645        {
1646            for (; __begin1 != __end1; ++__begin1, (void) ++__begin2)
1647                construct(__a, _VSTD::__to_raw_pointer(__begin2), *__begin1);
1648        }
1649
1650    template <class _Tp>
1651        _LIBCPP_INLINE_VISIBILITY
1652        static
1653        typename enable_if
1654        <
1655            (is_same<allocator_type, allocator<_Tp> >::value
1656                || !__has_construct<allocator_type, _Tp*, _Tp>::value) &&
1657             is_trivially_move_constructible<_Tp>::value,
1658            void
1659        >::type
1660        __construct_range_forward(allocator_type&, _Tp* __begin1, _Tp* __end1, _Tp*& __begin2)
1661        {
1662            typedef typename remove_const<_Tp>::type _Vp;
1663            ptrdiff_t _Np = __end1 - __begin1;
1664            if (_Np > 0)
1665            {
1666                _VSTD::memcpy(const_cast<_Vp*>(__begin2), __begin1, _Np * sizeof(_Tp));
1667                __begin2 += _Np;
1668            }
1669        }
1670
1671    template <class _Ptr>
1672        _LIBCPP_INLINE_VISIBILITY
1673        static
1674        void
1675        __construct_backward(allocator_type& __a, _Ptr __begin1, _Ptr __end1, _Ptr& __end2)
1676        {
1677            while (__end1 != __begin1)
1678            {
1679                construct(__a, _VSTD::__to_raw_pointer(__end2-1), _VSTD::move_if_noexcept(*--__end1));
1680                --__end2;
1681            }
1682        }
1683
1684    template <class _Tp>
1685        _LIBCPP_INLINE_VISIBILITY
1686        static
1687        typename enable_if
1688        <
1689            (is_same<allocator_type, allocator<_Tp> >::value
1690                || !__has_construct<allocator_type, _Tp*, _Tp>::value) &&
1691             is_trivially_move_constructible<_Tp>::value,
1692            void
1693        >::type
1694        __construct_backward(allocator_type&, _Tp* __begin1, _Tp* __end1, _Tp*& __end2)
1695        {
1696            ptrdiff_t _Np = __end1 - __begin1;
1697            __end2 -= _Np;
1698            if (_Np > 0)
1699                _VSTD::memcpy(__end2, __begin1, _Np * sizeof(_Tp));
1700        }
1701
1702private:
1703
1704    _LIBCPP_INLINE_VISIBILITY
1705    static pointer __allocate(allocator_type& __a, size_type __n,
1706        const_void_pointer __hint, true_type)
1707        {return __a.allocate(__n, __hint);}
1708    _LIBCPP_INLINE_VISIBILITY
1709    static pointer __allocate(allocator_type& __a, size_type __n,
1710        const_void_pointer, false_type)
1711        {return __a.allocate(__n);}
1712
1713#ifndef _LIBCPP_HAS_NO_VARIADICS
1714    template <class _Tp, class... _Args>
1715        _LIBCPP_INLINE_VISIBILITY
1716        static void __construct(true_type, allocator_type& __a, _Tp* __p, _Args&&... __args)
1717            {__a.construct(__p, _VSTD::forward<_Args>(__args)...);}
1718    template <class _Tp, class... _Args>
1719        _LIBCPP_INLINE_VISIBILITY
1720        static void __construct(false_type, allocator_type&, _Tp* __p, _Args&&... __args)
1721            {
1722                ::new ((void*)__p) _Tp(_VSTD::forward<_Args>(__args)...);
1723            }
1724#endif  // _LIBCPP_HAS_NO_VARIADICS
1725
1726    template <class _Tp>
1727        _LIBCPP_INLINE_VISIBILITY
1728        static void __destroy(true_type, allocator_type& __a, _Tp* __p)
1729            {__a.destroy(__p);}
1730    template <class _Tp>
1731        _LIBCPP_INLINE_VISIBILITY
1732        static void __destroy(false_type, allocator_type&, _Tp* __p)
1733            {
1734                __p->~_Tp();
1735            }
1736
1737    _LIBCPP_INLINE_VISIBILITY
1738    static size_type __max_size(true_type, const allocator_type& __a) _NOEXCEPT
1739            {return __a.max_size();}
1740    _LIBCPP_INLINE_VISIBILITY
1741    static size_type __max_size(false_type, const allocator_type&) _NOEXCEPT
1742            {return numeric_limits<size_type>::max() / sizeof(value_type);}
1743
1744    _LIBCPP_INLINE_VISIBILITY
1745    static allocator_type
1746        __select_on_container_copy_construction(true_type, const allocator_type& __a)
1747            {return __a.select_on_container_copy_construction();}
1748    _LIBCPP_INLINE_VISIBILITY
1749    static allocator_type
1750        __select_on_container_copy_construction(false_type, const allocator_type& __a)
1751            {return __a;}
1752};
1753
1754template <class _Traits, class _Tp>
1755struct __rebind_alloc_helper
1756{
1757#ifndef _LIBCPP_CXX03_LANG
1758    typedef typename _Traits::template rebind_alloc<_Tp>        type;
1759#else
1760    typedef typename _Traits::template rebind_alloc<_Tp>::other type;
1761#endif
1762};
1763
1764// allocator
1765
1766template <class _Tp>
1767class _LIBCPP_TEMPLATE_VIS allocator
1768{
1769public:
1770    typedef size_t            size_type;
1771    typedef ptrdiff_t         difference_type;
1772    typedef _Tp*              pointer;
1773    typedef const _Tp*        const_pointer;
1774    typedef _Tp&              reference;
1775    typedef const _Tp&        const_reference;
1776    typedef _Tp               value_type;
1777
1778    typedef true_type propagate_on_container_move_assignment;
1779    typedef true_type is_always_equal;
1780
1781    template <class _Up> struct rebind {typedef allocator<_Up> other;};
1782
1783    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
1784    allocator() _NOEXCEPT {}
1785
1786    template <class _Up>
1787    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
1788    allocator(const allocator<_Up>&) _NOEXCEPT {}
1789
1790    _LIBCPP_INLINE_VISIBILITY pointer address(reference __x) const _NOEXCEPT
1791        {return _VSTD::addressof(__x);}
1792    _LIBCPP_INLINE_VISIBILITY const_pointer address(const_reference __x) const _NOEXCEPT
1793        {return _VSTD::addressof(__x);}
1794    _LIBCPP_NODISCARD_AFTER_CXX17 _LIBCPP_INLINE_VISIBILITY
1795    pointer allocate(size_type __n, allocator<void>::const_pointer = 0)
1796        {
1797        if (__n > max_size())
1798            __throw_length_error("allocator<T>::allocate(size_t n)"
1799                                 " 'n' exceeds maximum supported size");
1800        return static_cast<pointer>(_VSTD::__libcpp_allocate(__n * sizeof(_Tp), __alignof(_Tp)));
1801        }
1802    _LIBCPP_INLINE_VISIBILITY void deallocate(pointer __p, size_type __n) _NOEXCEPT
1803        {_VSTD::__libcpp_deallocate((void*)__p, __n * sizeof(_Tp), __alignof(_Tp));}
1804    _LIBCPP_INLINE_VISIBILITY size_type max_size() const _NOEXCEPT
1805        {return size_type(~0) / sizeof(_Tp);}
1806#if !defined(_LIBCPP_HAS_NO_RVALUE_REFERENCES) && !defined(_LIBCPP_HAS_NO_VARIADICS)
1807    template <class _Up, class... _Args>
1808        _LIBCPP_INLINE_VISIBILITY
1809        void
1810        construct(_Up* __p, _Args&&... __args)
1811        {
1812            ::new((void*)__p) _Up(_VSTD::forward<_Args>(__args)...);
1813        }
1814#else  // !defined(_LIBCPP_HAS_NO_RVALUE_REFERENCES) && !defined(_LIBCPP_HAS_NO_VARIADICS)
1815        _LIBCPP_INLINE_VISIBILITY
1816        void
1817        construct(pointer __p)
1818        {
1819            ::new((void*)__p) _Tp();
1820        }
1821# if defined(_LIBCPP_HAS_NO_RVALUE_REFERENCES)
1822
1823    template <class _A0>
1824        _LIBCPP_INLINE_VISIBILITY
1825        void
1826        construct(pointer __p, _A0& __a0)
1827        {
1828            ::new((void*)__p) _Tp(__a0);
1829        }
1830    template <class _A0>
1831        _LIBCPP_INLINE_VISIBILITY
1832        void
1833        construct(pointer __p, const _A0& __a0)
1834        {
1835            ::new((void*)__p) _Tp(__a0);
1836        }
1837# endif  // defined(_LIBCPP_HAS_NO_RVALUE_REFERENCES)
1838    template <class _A0, class _A1>
1839        _LIBCPP_INLINE_VISIBILITY
1840        void
1841        construct(pointer __p, _A0& __a0, _A1& __a1)
1842        {
1843            ::new((void*)__p) _Tp(__a0, __a1);
1844        }
1845    template <class _A0, class _A1>
1846        _LIBCPP_INLINE_VISIBILITY
1847        void
1848        construct(pointer __p, const _A0& __a0, _A1& __a1)
1849        {
1850            ::new((void*)__p) _Tp(__a0, __a1);
1851        }
1852    template <class _A0, class _A1>
1853        _LIBCPP_INLINE_VISIBILITY
1854        void
1855        construct(pointer __p, _A0& __a0, const _A1& __a1)
1856        {
1857            ::new((void*)__p) _Tp(__a0, __a1);
1858        }
1859    template <class _A0, class _A1>
1860        _LIBCPP_INLINE_VISIBILITY
1861        void
1862        construct(pointer __p, const _A0& __a0, const _A1& __a1)
1863        {
1864            ::new((void*)__p) _Tp(__a0, __a1);
1865        }
1866#endif  // !defined(_LIBCPP_HAS_NO_RVALUE_REFERENCES) && !defined(_LIBCPP_HAS_NO_VARIADICS)
1867    _LIBCPP_INLINE_VISIBILITY void destroy(pointer __p) {__p->~_Tp();}
1868};
1869
1870template <class _Tp>
1871class _LIBCPP_TEMPLATE_VIS allocator<const _Tp>
1872{
1873public:
1874    typedef size_t            size_type;
1875    typedef ptrdiff_t         difference_type;
1876    typedef const _Tp*        pointer;
1877    typedef const _Tp*        const_pointer;
1878    typedef const _Tp&        reference;
1879    typedef const _Tp&        const_reference;
1880    typedef const _Tp         value_type;
1881
1882    typedef true_type propagate_on_container_move_assignment;
1883    typedef true_type is_always_equal;
1884
1885    template <class _Up> struct rebind {typedef allocator<_Up> other;};
1886
1887    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
1888    allocator() _NOEXCEPT {}
1889
1890    template <class _Up>
1891    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
1892    allocator(const allocator<_Up>&) _NOEXCEPT {}
1893
1894    _LIBCPP_INLINE_VISIBILITY const_pointer address(const_reference __x) const _NOEXCEPT
1895        {return _VSTD::addressof(__x);}
1896    _LIBCPP_INLINE_VISIBILITY pointer allocate(size_type __n, allocator<void>::const_pointer = 0)
1897    {
1898        if (__n > max_size())
1899            __throw_length_error("allocator<const T>::allocate(size_t n)"
1900                                 " 'n' exceeds maximum supported size");
1901        return static_cast<pointer>(_VSTD::__libcpp_allocate(__n * sizeof(_Tp), __alignof(_Tp)));
1902    }
1903    _LIBCPP_INLINE_VISIBILITY void deallocate(pointer __p, size_type __n) _NOEXCEPT
1904        {_VSTD::__libcpp_deallocate((void*) const_cast<_Tp *>(__p), __n * sizeof(_Tp), __alignof(_Tp));}
1905    _LIBCPP_INLINE_VISIBILITY size_type max_size() const _NOEXCEPT
1906        {return size_type(~0) / sizeof(_Tp);}
1907#if !defined(_LIBCPP_HAS_NO_RVALUE_REFERENCES) && !defined(_LIBCPP_HAS_NO_VARIADICS)
1908    template <class _Up, class... _Args>
1909        _LIBCPP_INLINE_VISIBILITY
1910        void
1911        construct(_Up* __p, _Args&&... __args)
1912        {
1913            ::new((void*)__p) _Up(_VSTD::forward<_Args>(__args)...);
1914        }
1915#else  // !defined(_LIBCPP_HAS_NO_RVALUE_REFERENCES) && !defined(_LIBCPP_HAS_NO_VARIADICS)
1916        _LIBCPP_INLINE_VISIBILITY
1917        void
1918        construct(pointer __p)
1919        {
1920            ::new((void*) const_cast<_Tp *>(__p)) _Tp();
1921        }
1922# if defined(_LIBCPP_HAS_NO_RVALUE_REFERENCES)
1923
1924    template <class _A0>
1925        _LIBCPP_INLINE_VISIBILITY
1926        void
1927        construct(pointer __p, _A0& __a0)
1928        {
1929            ::new((void*) const_cast<_Tp *>(__p)) _Tp(__a0);
1930        }
1931    template <class _A0>
1932        _LIBCPP_INLINE_VISIBILITY
1933        void
1934        construct(pointer __p, const _A0& __a0)
1935        {
1936            ::new((void*) const_cast<_Tp *>(__p)) _Tp(__a0);
1937        }
1938# endif  // defined(_LIBCPP_HAS_NO_RVALUE_REFERENCES)
1939    template <class _A0, class _A1>
1940        _LIBCPP_INLINE_VISIBILITY
1941        void
1942        construct(pointer __p, _A0& __a0, _A1& __a1)
1943        {
1944            ::new((void*) const_cast<_Tp *>(__p)) _Tp(__a0, __a1);
1945        }
1946    template <class _A0, class _A1>
1947        _LIBCPP_INLINE_VISIBILITY
1948        void
1949        construct(pointer __p, const _A0& __a0, _A1& __a1)
1950        {
1951            ::new((void*) const_cast<_Tp *>(__p)) _Tp(__a0, __a1);
1952        }
1953    template <class _A0, class _A1>
1954        _LIBCPP_INLINE_VISIBILITY
1955        void
1956        construct(pointer __p, _A0& __a0, const _A1& __a1)
1957        {
1958            ::new((void*) const_cast<_Tp *>(__p)) _Tp(__a0, __a1);
1959        }
1960    template <class _A0, class _A1>
1961        _LIBCPP_INLINE_VISIBILITY
1962        void
1963        construct(pointer __p, const _A0& __a0, const _A1& __a1)
1964        {
1965            ::new((void*) const_cast<_Tp *>(__p)) _Tp(__a0, __a1);
1966        }
1967#endif  // !defined(_LIBCPP_HAS_NO_RVALUE_REFERENCES) && !defined(_LIBCPP_HAS_NO_VARIADICS)
1968    _LIBCPP_INLINE_VISIBILITY void destroy(pointer __p) {__p->~_Tp();}
1969};
1970
1971template <class _Tp, class _Up>
1972inline _LIBCPP_INLINE_VISIBILITY
1973bool operator==(const allocator<_Tp>&, const allocator<_Up>&) _NOEXCEPT {return true;}
1974
1975template <class _Tp, class _Up>
1976inline _LIBCPP_INLINE_VISIBILITY
1977bool operator!=(const allocator<_Tp>&, const allocator<_Up>&) _NOEXCEPT {return false;}
1978
1979template <class _OutputIterator, class _Tp>
1980class _LIBCPP_TEMPLATE_VIS raw_storage_iterator
1981    : public iterator<output_iterator_tag,
1982                      _Tp,                                         // purposefully not C++03
1983                      ptrdiff_t,                                   // purposefully not C++03
1984                      _Tp*,                                        // purposefully not C++03
1985                      raw_storage_iterator<_OutputIterator, _Tp>&> // purposefully not C++03
1986{
1987private:
1988    _OutputIterator __x_;
1989public:
1990    _LIBCPP_INLINE_VISIBILITY explicit raw_storage_iterator(_OutputIterator __x) : __x_(__x) {}
1991    _LIBCPP_INLINE_VISIBILITY raw_storage_iterator& operator*() {return *this;}
1992    _LIBCPP_INLINE_VISIBILITY raw_storage_iterator& operator=(const _Tp& __element)
1993        {::new(_VSTD::addressof(*__x_)) _Tp(__element); return *this;}
1994#if _LIBCPP_STD_VER >= 14
1995    _LIBCPP_INLINE_VISIBILITY raw_storage_iterator& operator=(_Tp&& __element)
1996        {::new(_VSTD::addressof(*__x_)) _Tp(_VSTD::move(__element)); return *this;}
1997#endif
1998    _LIBCPP_INLINE_VISIBILITY raw_storage_iterator& operator++() {++__x_; return *this;}
1999    _LIBCPP_INLINE_VISIBILITY raw_storage_iterator  operator++(int)
2000        {raw_storage_iterator __t(*this); ++__x_; return __t;}
2001#if _LIBCPP_STD_VER >= 14
2002    _LIBCPP_INLINE_VISIBILITY _OutputIterator base() const { return __x_; }
2003#endif
2004};
2005
2006template <class _Tp>
2007_LIBCPP_NODISCARD_EXT _LIBCPP_NO_CFI
2008pair<_Tp*, ptrdiff_t>
2009get_temporary_buffer(ptrdiff_t __n) _NOEXCEPT
2010{
2011    pair<_Tp*, ptrdiff_t> __r(0, 0);
2012    const ptrdiff_t __m = (~ptrdiff_t(0) ^
2013                           ptrdiff_t(ptrdiff_t(1) << (sizeof(ptrdiff_t) * __CHAR_BIT__ - 1)))
2014                           / sizeof(_Tp);
2015    if (__n > __m)
2016        __n = __m;
2017    while (__n > 0)
2018    {
2019#if !defined(_LIBCPP_HAS_NO_ALIGNED_ALLOCATION)
2020    if (__is_overaligned_for_new(__alignof(_Tp)))
2021        {
2022            std::align_val_t __al =
2023                std::align_val_t(std::alignment_of<_Tp>::value);
2024            __r.first = static_cast<_Tp*>(::operator new(
2025                __n * sizeof(_Tp), __al, nothrow));
2026        } else {
2027            __r.first = static_cast<_Tp*>(::operator new(
2028                __n * sizeof(_Tp), nothrow));
2029        }
2030#else
2031    if (__is_overaligned_for_new(__alignof(_Tp)))
2032        {
2033            // Since aligned operator new is unavailable, return an empty
2034            // buffer rather than one with invalid alignment.
2035            return __r;
2036        }
2037
2038        __r.first = static_cast<_Tp*>(::operator new(__n * sizeof(_Tp), nothrow));
2039#endif
2040
2041        if (__r.first)
2042        {
2043            __r.second = __n;
2044            break;
2045        }
2046        __n /= 2;
2047    }
2048    return __r;
2049}
2050
2051template <class _Tp>
2052inline _LIBCPP_INLINE_VISIBILITY
2053void return_temporary_buffer(_Tp* __p) _NOEXCEPT
2054{
2055  _VSTD::__libcpp_deallocate_unsized((void*)__p, __alignof(_Tp));
2056}
2057
2058#if _LIBCPP_STD_VER <= 14 || defined(_LIBCPP_ENABLE_CXX17_REMOVED_AUTO_PTR)
2059template <class _Tp>
2060struct _LIBCPP_DEPRECATED_IN_CXX11 auto_ptr_ref
2061{
2062    _Tp* __ptr_;
2063};
2064
2065template<class _Tp>
2066class _LIBCPP_TEMPLATE_VIS _LIBCPP_DEPRECATED_IN_CXX11 auto_ptr
2067{
2068private:
2069    _Tp* __ptr_;
2070public:
2071    typedef _Tp element_type;
2072
2073    _LIBCPP_INLINE_VISIBILITY explicit auto_ptr(_Tp* __p = 0) throw() : __ptr_(__p) {}
2074    _LIBCPP_INLINE_VISIBILITY auto_ptr(auto_ptr& __p) throw() : __ptr_(__p.release()) {}
2075    template<class _Up> _LIBCPP_INLINE_VISIBILITY auto_ptr(auto_ptr<_Up>& __p) throw()
2076        : __ptr_(__p.release()) {}
2077    _LIBCPP_INLINE_VISIBILITY auto_ptr& operator=(auto_ptr& __p) throw()
2078        {reset(__p.release()); return *this;}
2079    template<class _Up> _LIBCPP_INLINE_VISIBILITY auto_ptr& operator=(auto_ptr<_Up>& __p) throw()
2080        {reset(__p.release()); return *this;}
2081    _LIBCPP_INLINE_VISIBILITY auto_ptr& operator=(auto_ptr_ref<_Tp> __p) throw()
2082        {reset(__p.__ptr_); return *this;}
2083    _LIBCPP_INLINE_VISIBILITY ~auto_ptr() throw() {delete __ptr_;}
2084
2085    _LIBCPP_INLINE_VISIBILITY _Tp& operator*() const throw()
2086        {return *__ptr_;}
2087    _LIBCPP_INLINE_VISIBILITY _Tp* operator->() const throw() {return __ptr_;}
2088    _LIBCPP_INLINE_VISIBILITY _Tp* get() const throw() {return __ptr_;}
2089    _LIBCPP_INLINE_VISIBILITY _Tp* release() throw()
2090    {
2091        _Tp* __t = __ptr_;
2092        __ptr_ = 0;
2093        return __t;
2094    }
2095    _LIBCPP_INLINE_VISIBILITY void reset(_Tp* __p = 0) throw()
2096    {
2097        if (__ptr_ != __p)
2098            delete __ptr_;
2099        __ptr_ = __p;
2100    }
2101
2102    _LIBCPP_INLINE_VISIBILITY auto_ptr(auto_ptr_ref<_Tp> __p) throw() : __ptr_(__p.__ptr_) {}
2103    template<class _Up> _LIBCPP_INLINE_VISIBILITY operator auto_ptr_ref<_Up>() throw()
2104        {auto_ptr_ref<_Up> __t; __t.__ptr_ = release(); return __t;}
2105    template<class _Up> _LIBCPP_INLINE_VISIBILITY operator auto_ptr<_Up>() throw()
2106        {return auto_ptr<_Up>(release());}
2107};
2108
2109template <>
2110class _LIBCPP_TEMPLATE_VIS _LIBCPP_DEPRECATED_IN_CXX11 auto_ptr<void>
2111{
2112public:
2113    typedef void element_type;
2114};
2115#endif
2116
2117template <class _Tp, int _Idx,
2118          bool _CanBeEmptyBase =
2119              is_empty<_Tp>::value && !__libcpp_is_final<_Tp>::value>
2120struct __compressed_pair_elem {
2121  typedef _Tp _ParamT;
2122  typedef _Tp& reference;
2123  typedef const _Tp& const_reference;
2124
2125#ifndef _LIBCPP_CXX03_LANG
2126  _LIBCPP_INLINE_VISIBILITY constexpr __compressed_pair_elem() : __value_() {}
2127
2128  template <class _Up, class = typename enable_if<
2129      !is_same<__compressed_pair_elem, typename decay<_Up>::type>::value
2130  >::type>
2131  _LIBCPP_INLINE_VISIBILITY
2132  constexpr explicit
2133  __compressed_pair_elem(_Up&& __u)
2134      : __value_(_VSTD::forward<_Up>(__u))
2135    {
2136    }
2137
2138  template <class... _Args, size_t... _Indexes>
2139  _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14
2140  __compressed_pair_elem(piecewise_construct_t, tuple<_Args...> __args,
2141                         __tuple_indices<_Indexes...>)
2142      : __value_(_VSTD::forward<_Args>(_VSTD::get<_Indexes>(__args))...) {}
2143#else
2144  _LIBCPP_INLINE_VISIBILITY __compressed_pair_elem() : __value_() {}
2145  _LIBCPP_INLINE_VISIBILITY
2146  __compressed_pair_elem(_ParamT __p) : __value_(std::forward<_ParamT>(__p)) {}
2147#endif
2148
2149  _LIBCPP_INLINE_VISIBILITY reference __get() _NOEXCEPT { return __value_; }
2150  _LIBCPP_INLINE_VISIBILITY
2151  const_reference __get() const _NOEXCEPT { return __value_; }
2152
2153private:
2154  _Tp __value_;
2155};
2156
2157template <class _Tp, int _Idx>
2158struct __compressed_pair_elem<_Tp, _Idx, true> : private _Tp {
2159  typedef _Tp _ParamT;
2160  typedef _Tp& reference;
2161  typedef const _Tp& const_reference;
2162  typedef _Tp __value_type;
2163
2164#ifndef _LIBCPP_CXX03_LANG
2165  _LIBCPP_INLINE_VISIBILITY constexpr __compressed_pair_elem() = default;
2166
2167  template <class _Up, class = typename enable_if<
2168        !is_same<__compressed_pair_elem, typename decay<_Up>::type>::value
2169  >::type>
2170  _LIBCPP_INLINE_VISIBILITY
2171  constexpr explicit
2172  __compressed_pair_elem(_Up&& __u)
2173      : __value_type(_VSTD::forward<_Up>(__u))
2174  {}
2175
2176  template <class... _Args, size_t... _Indexes>
2177  _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14
2178  __compressed_pair_elem(piecewise_construct_t, tuple<_Args...> __args,
2179                         __tuple_indices<_Indexes...>)
2180      : __value_type(_VSTD::forward<_Args>(_VSTD::get<_Indexes>(__args))...) {}
2181#else
2182  _LIBCPP_INLINE_VISIBILITY __compressed_pair_elem() : __value_type() {}
2183  _LIBCPP_INLINE_VISIBILITY
2184  __compressed_pair_elem(_ParamT __p)
2185      : __value_type(std::forward<_ParamT>(__p)) {}
2186#endif
2187
2188  _LIBCPP_INLINE_VISIBILITY reference __get() _NOEXCEPT { return *this; }
2189  _LIBCPP_INLINE_VISIBILITY
2190  const_reference __get() const _NOEXCEPT { return *this; }
2191};
2192
2193// Tag used to construct the second element of the compressed pair.
2194struct __second_tag {};
2195
2196template <class _T1, class _T2>
2197class __compressed_pair : private __compressed_pair_elem<_T1, 0>,
2198                          private __compressed_pair_elem<_T2, 1> {
2199  typedef __compressed_pair_elem<_T1, 0> _Base1;
2200  typedef __compressed_pair_elem<_T2, 1> _Base2;
2201
2202  // NOTE: This static assert should never fire because __compressed_pair
2203  // is *almost never* used in a scenario where it's possible for T1 == T2.
2204  // (The exception is std::function where it is possible that the function
2205  //  object and the allocator have the same type).
2206  static_assert((!is_same<_T1, _T2>::value),
2207    "__compressed_pair cannot be instantated when T1 and T2 are the same type; "
2208    "The current implementation is NOT ABI-compatible with the previous "
2209    "implementation for this configuration");
2210
2211public:
2212#ifndef _LIBCPP_CXX03_LANG
2213  template <bool _Dummy = true,
2214      class = typename enable_if<
2215          __dependent_type<is_default_constructible<_T1>, _Dummy>::value &&
2216          __dependent_type<is_default_constructible<_T2>, _Dummy>::value
2217      >::type
2218  >
2219  _LIBCPP_INLINE_VISIBILITY
2220  constexpr __compressed_pair() {}
2221
2222  template <class _Tp, typename enable_if<!is_same<typename decay<_Tp>::type,
2223                                                   __compressed_pair>::value,
2224                                          bool>::type = true>
2225  _LIBCPP_INLINE_VISIBILITY constexpr explicit
2226  __compressed_pair(_Tp&& __t)
2227      : _Base1(std::forward<_Tp>(__t)), _Base2() {}
2228
2229  template <class _Tp>
2230  _LIBCPP_INLINE_VISIBILITY constexpr
2231  __compressed_pair(__second_tag, _Tp&& __t)
2232      : _Base1(), _Base2(std::forward<_Tp>(__t)) {}
2233
2234  template <class _U1, class _U2>
2235  _LIBCPP_INLINE_VISIBILITY constexpr
2236  __compressed_pair(_U1&& __t1, _U2&& __t2)
2237      : _Base1(std::forward<_U1>(__t1)), _Base2(std::forward<_U2>(__t2)) {}
2238
2239  template <class... _Args1, class... _Args2>
2240  _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14
2241  __compressed_pair(piecewise_construct_t __pc, tuple<_Args1...> __first_args,
2242                    tuple<_Args2...> __second_args)
2243      : _Base1(__pc, _VSTD::move(__first_args),
2244               typename __make_tuple_indices<sizeof...(_Args1)>::type()),
2245        _Base2(__pc, _VSTD::move(__second_args),
2246               typename __make_tuple_indices<sizeof...(_Args2)>::type()) {}
2247
2248#else
2249  _LIBCPP_INLINE_VISIBILITY
2250  __compressed_pair() {}
2251
2252  _LIBCPP_INLINE_VISIBILITY explicit
2253  __compressed_pair(_T1 __t1) : _Base1(_VSTD::forward<_T1>(__t1)) {}
2254
2255  _LIBCPP_INLINE_VISIBILITY
2256  __compressed_pair(__second_tag, _T2 __t2)
2257      : _Base1(), _Base2(_VSTD::forward<_T2>(__t2)) {}
2258
2259  _LIBCPP_INLINE_VISIBILITY
2260  __compressed_pair(_T1 __t1, _T2 __t2)
2261      : _Base1(_VSTD::forward<_T1>(__t1)), _Base2(_VSTD::forward<_T2>(__t2)) {}
2262#endif
2263
2264  _LIBCPP_INLINE_VISIBILITY
2265  typename _Base1::reference first() _NOEXCEPT {
2266    return static_cast<_Base1&>(*this).__get();
2267  }
2268
2269  _LIBCPP_INLINE_VISIBILITY
2270  typename _Base1::const_reference first() const _NOEXCEPT {
2271    return static_cast<_Base1 const&>(*this).__get();
2272  }
2273
2274  _LIBCPP_INLINE_VISIBILITY
2275  typename _Base2::reference second() _NOEXCEPT {
2276    return static_cast<_Base2&>(*this).__get();
2277  }
2278
2279  _LIBCPP_INLINE_VISIBILITY
2280  typename _Base2::const_reference second() const _NOEXCEPT {
2281    return static_cast<_Base2 const&>(*this).__get();
2282  }
2283
2284  _LIBCPP_INLINE_VISIBILITY
2285  void swap(__compressed_pair& __x)
2286    _NOEXCEPT_(__is_nothrow_swappable<_T1>::value &&
2287               __is_nothrow_swappable<_T2>::value)
2288  {
2289    using std::swap;
2290    swap(first(), __x.first());
2291    swap(second(), __x.second());
2292  }
2293};
2294
2295template <class _T1, class _T2>
2296inline _LIBCPP_INLINE_VISIBILITY
2297void swap(__compressed_pair<_T1, _T2>& __x, __compressed_pair<_T1, _T2>& __y)
2298    _NOEXCEPT_(__is_nothrow_swappable<_T1>::value &&
2299               __is_nothrow_swappable<_T2>::value) {
2300  __x.swap(__y);
2301}
2302
2303// default_delete
2304
2305template <class _Tp>
2306struct _LIBCPP_TEMPLATE_VIS default_delete {
2307    static_assert(!is_function<_Tp>::value,
2308                  "default_delete cannot be instantiated for function types");
2309#ifndef _LIBCPP_CXX03_LANG
2310  _LIBCPP_INLINE_VISIBILITY constexpr default_delete() noexcept = default;
2311#else
2312  _LIBCPP_INLINE_VISIBILITY default_delete() {}
2313#endif
2314  template <class _Up>
2315  _LIBCPP_INLINE_VISIBILITY
2316  default_delete(const default_delete<_Up>&,
2317                 typename enable_if<is_convertible<_Up*, _Tp*>::value>::type* =
2318                     0) _NOEXCEPT {}
2319
2320  _LIBCPP_INLINE_VISIBILITY void operator()(_Tp* __ptr) const _NOEXCEPT {
2321    static_assert(sizeof(_Tp) > 0,
2322                  "default_delete can not delete incomplete type");
2323    static_assert(!is_void<_Tp>::value,
2324                  "default_delete can not delete incomplete type");
2325    delete __ptr;
2326  }
2327};
2328
2329template <class _Tp>
2330struct _LIBCPP_TEMPLATE_VIS default_delete<_Tp[]> {
2331private:
2332  template <class _Up>
2333  struct _EnableIfConvertible
2334      : enable_if<is_convertible<_Up(*)[], _Tp(*)[]>::value> {};
2335
2336public:
2337#ifndef _LIBCPP_CXX03_LANG
2338  _LIBCPP_INLINE_VISIBILITY constexpr default_delete() noexcept = default;
2339#else
2340  _LIBCPP_INLINE_VISIBILITY default_delete() {}
2341#endif
2342
2343  template <class _Up>
2344  _LIBCPP_INLINE_VISIBILITY
2345  default_delete(const default_delete<_Up[]>&,
2346                 typename _EnableIfConvertible<_Up>::type* = 0) _NOEXCEPT {}
2347
2348  template <class _Up>
2349  _LIBCPP_INLINE_VISIBILITY
2350  typename _EnableIfConvertible<_Up>::type
2351  operator()(_Up* __ptr) const _NOEXCEPT {
2352    static_assert(sizeof(_Tp) > 0,
2353                  "default_delete can not delete incomplete type");
2354    static_assert(!is_void<_Tp>::value,
2355                  "default_delete can not delete void type");
2356    delete[] __ptr;
2357  }
2358};
2359
2360
2361
2362#ifndef _LIBCPP_CXX03_LANG
2363template <class _Deleter>
2364struct __unique_ptr_deleter_sfinae {
2365  static_assert(!is_reference<_Deleter>::value, "incorrect specialization");
2366  typedef const _Deleter& __lval_ref_type;
2367  typedef _Deleter&& __good_rval_ref_type;
2368  typedef true_type __enable_rval_overload;
2369};
2370
2371template <class _Deleter>
2372struct __unique_ptr_deleter_sfinae<_Deleter const&> {
2373  typedef const _Deleter& __lval_ref_type;
2374  typedef const _Deleter&& __bad_rval_ref_type;
2375  typedef false_type __enable_rval_overload;
2376};
2377
2378template <class _Deleter>
2379struct __unique_ptr_deleter_sfinae<_Deleter&> {
2380  typedef _Deleter& __lval_ref_type;
2381  typedef _Deleter&& __bad_rval_ref_type;
2382  typedef false_type __enable_rval_overload;
2383};
2384#endif // !defined(_LIBCPP_CXX03_LANG)
2385
2386template <class _Tp, class _Dp = default_delete<_Tp> >
2387class _LIBCPP_TEMPLATE_VIS unique_ptr {
2388public:
2389  typedef _Tp element_type;
2390  typedef _Dp deleter_type;
2391  typedef typename __pointer_type<_Tp, deleter_type>::type pointer;
2392
2393  static_assert(!is_rvalue_reference<deleter_type>::value,
2394                "the specified deleter type cannot be an rvalue reference");
2395
2396private:
2397  __compressed_pair<pointer, deleter_type> __ptr_;
2398
2399  struct __nat { int __for_bool_; };
2400
2401#ifndef _LIBCPP_CXX03_LANG
2402  typedef __unique_ptr_deleter_sfinae<_Dp> _DeleterSFINAE;
2403
2404  template <bool _Dummy>
2405  using _LValRefType =
2406      typename __dependent_type<_DeleterSFINAE, _Dummy>::__lval_ref_type;
2407
2408  template <bool _Dummy>
2409  using _GoodRValRefType =
2410      typename __dependent_type<_DeleterSFINAE, _Dummy>::__good_rval_ref_type;
2411
2412  template <bool _Dummy>
2413  using _BadRValRefType =
2414      typename __dependent_type<_DeleterSFINAE, _Dummy>::__bad_rval_ref_type;
2415
2416  template <bool _Dummy, class _Deleter = typename __dependent_type<
2417                             __identity<deleter_type>, _Dummy>::type>
2418  using _EnableIfDeleterDefaultConstructible =
2419      typename enable_if<is_default_constructible<_Deleter>::value &&
2420                         !is_pointer<_Deleter>::value>::type;
2421
2422  template <class _ArgType>
2423  using _EnableIfDeleterConstructible =
2424      typename enable_if<is_constructible<deleter_type, _ArgType>::value>::type;
2425
2426  template <class _UPtr, class _Up>
2427  using _EnableIfMoveConvertible = typename enable_if<
2428      is_convertible<typename _UPtr::pointer, pointer>::value &&
2429      !is_array<_Up>::value
2430  >::type;
2431
2432  template <class _UDel>
2433  using _EnableIfDeleterConvertible = typename enable_if<
2434      (is_reference<_Dp>::value && is_same<_Dp, _UDel>::value) ||
2435      (!is_reference<_Dp>::value && is_convertible<_UDel, _Dp>::value)
2436    >::type;
2437
2438  template <class _UDel>
2439  using _EnableIfDeleterAssignable = typename enable_if<
2440      is_assignable<_Dp&, _UDel&&>::value
2441    >::type;
2442
2443public:
2444  template <bool _Dummy = true,
2445            class = _EnableIfDeleterDefaultConstructible<_Dummy>>
2446  _LIBCPP_INLINE_VISIBILITY
2447  constexpr unique_ptr() noexcept : __ptr_(pointer()) {}
2448
2449  template <bool _Dummy = true,
2450            class = _EnableIfDeleterDefaultConstructible<_Dummy>>
2451  _LIBCPP_INLINE_VISIBILITY
2452  constexpr unique_ptr(nullptr_t) noexcept : __ptr_(pointer()) {}
2453
2454  template <bool _Dummy = true,
2455            class = _EnableIfDeleterDefaultConstructible<_Dummy>>
2456  _LIBCPP_INLINE_VISIBILITY
2457  explicit unique_ptr(pointer __p) noexcept : __ptr_(__p) {}
2458
2459  template <bool _Dummy = true,
2460            class = _EnableIfDeleterConstructible<_LValRefType<_Dummy>>>
2461  _LIBCPP_INLINE_VISIBILITY
2462  unique_ptr(pointer __p, _LValRefType<_Dummy> __d) noexcept
2463      : __ptr_(__p, __d) {}
2464
2465  template <bool _Dummy = true,
2466            class = _EnableIfDeleterConstructible<_GoodRValRefType<_Dummy>>>
2467  _LIBCPP_INLINE_VISIBILITY
2468  unique_ptr(pointer __p, _GoodRValRefType<_Dummy> __d) noexcept
2469      : __ptr_(__p, _VSTD::move(__d)) {
2470    static_assert(!is_reference<deleter_type>::value,
2471                  "rvalue deleter bound to reference");
2472  }
2473
2474  template <bool _Dummy = true,
2475            class = _EnableIfDeleterConstructible<_BadRValRefType<_Dummy>>>
2476  _LIBCPP_INLINE_VISIBILITY
2477  unique_ptr(pointer __p, _BadRValRefType<_Dummy> __d) = delete;
2478
2479  _LIBCPP_INLINE_VISIBILITY
2480  unique_ptr(unique_ptr&& __u) noexcept
2481      : __ptr_(__u.release(), _VSTD::forward<deleter_type>(__u.get_deleter())) {
2482  }
2483
2484  template <class _Up, class _Ep,
2485      class = _EnableIfMoveConvertible<unique_ptr<_Up, _Ep>, _Up>,
2486      class = _EnableIfDeleterConvertible<_Ep>
2487  >
2488  _LIBCPP_INLINE_VISIBILITY
2489  unique_ptr(unique_ptr<_Up, _Ep>&& __u) _NOEXCEPT
2490      : __ptr_(__u.release(), _VSTD::forward<_Ep>(__u.get_deleter())) {}
2491
2492#if _LIBCPP_STD_VER <= 14 || defined(_LIBCPP_ENABLE_CXX17_REMOVED_AUTO_PTR)
2493  template <class _Up>
2494  _LIBCPP_INLINE_VISIBILITY
2495  unique_ptr(auto_ptr<_Up>&& __p,
2496             typename enable_if<is_convertible<_Up*, _Tp*>::value &&
2497                                    is_same<_Dp, default_delete<_Tp>>::value,
2498                                __nat>::type = __nat()) _NOEXCEPT
2499      : __ptr_(__p.release()) {}
2500#endif
2501
2502  _LIBCPP_INLINE_VISIBILITY
2503  unique_ptr& operator=(unique_ptr&& __u) _NOEXCEPT {
2504    reset(__u.release());
2505    __ptr_.second() = _VSTD::forward<deleter_type>(__u.get_deleter());
2506    return *this;
2507  }
2508
2509  template <class _Up, class _Ep,
2510      class = _EnableIfMoveConvertible<unique_ptr<_Up, _Ep>, _Up>,
2511      class = _EnableIfDeleterAssignable<_Ep>
2512  >
2513  _LIBCPP_INLINE_VISIBILITY
2514  unique_ptr& operator=(unique_ptr<_Up, _Ep>&& __u) _NOEXCEPT {
2515    reset(__u.release());
2516    __ptr_.second() = _VSTD::forward<_Ep>(__u.get_deleter());
2517    return *this;
2518  }
2519
2520#else  // _LIBCPP_CXX03_LANG
2521private:
2522  unique_ptr(unique_ptr&);
2523  template <class _Up, class _Ep> unique_ptr(unique_ptr<_Up, _Ep>&);
2524
2525  unique_ptr& operator=(unique_ptr&);
2526  template <class _Up, class _Ep> unique_ptr& operator=(unique_ptr<_Up, _Ep>&);
2527
2528public:
2529  _LIBCPP_INLINE_VISIBILITY
2530  unique_ptr() : __ptr_(pointer())
2531  {
2532    static_assert(!is_pointer<deleter_type>::value,
2533                  "unique_ptr constructed with null function pointer deleter");
2534    static_assert(is_default_constructible<deleter_type>::value,
2535                  "unique_ptr::deleter_type is not default constructible");
2536  }
2537  _LIBCPP_INLINE_VISIBILITY
2538  unique_ptr(nullptr_t) : __ptr_(pointer())
2539  {
2540    static_assert(!is_pointer<deleter_type>::value,
2541                  "unique_ptr constructed with null function pointer deleter");
2542  }
2543  _LIBCPP_INLINE_VISIBILITY
2544  explicit unique_ptr(pointer __p)
2545      : __ptr_(_VSTD::move(__p)) {
2546    static_assert(!is_pointer<deleter_type>::value,
2547                  "unique_ptr constructed with null function pointer deleter");
2548  }
2549
2550  _LIBCPP_INLINE_VISIBILITY
2551  operator __rv<unique_ptr>() {
2552    return __rv<unique_ptr>(*this);
2553  }
2554
2555  _LIBCPP_INLINE_VISIBILITY
2556  unique_ptr(__rv<unique_ptr> __u)
2557      : __ptr_(__u->release(),
2558               _VSTD::forward<deleter_type>(__u->get_deleter())) {}
2559
2560  template <class _Up, class _Ep>
2561  _LIBCPP_INLINE_VISIBILITY
2562  typename enable_if<
2563      !is_array<_Up>::value &&
2564          is_convertible<typename unique_ptr<_Up, _Ep>::pointer,
2565                         pointer>::value &&
2566          is_assignable<deleter_type&, _Ep&>::value,
2567      unique_ptr&>::type
2568  operator=(unique_ptr<_Up, _Ep> __u) {
2569    reset(__u.release());
2570    __ptr_.second() = _VSTD::forward<_Ep>(__u.get_deleter());
2571    return *this;
2572  }
2573
2574  _LIBCPP_INLINE_VISIBILITY
2575  unique_ptr(pointer __p, deleter_type __d)
2576      : __ptr_(_VSTD::move(__p), _VSTD::move(__d)) {}
2577#endif // _LIBCPP_CXX03_LANG
2578
2579#if _LIBCPP_STD_VER <= 14 || defined(_LIBCPP_ENABLE_CXX17_REMOVED_AUTO_PTR)
2580  template <class _Up>
2581  _LIBCPP_INLINE_VISIBILITY
2582      typename enable_if<is_convertible<_Up*, _Tp*>::value &&
2583                             is_same<_Dp, default_delete<_Tp> >::value,
2584                         unique_ptr&>::type
2585      operator=(auto_ptr<_Up> __p) {
2586    reset(__p.release());
2587    return *this;
2588  }
2589#endif
2590
2591  _LIBCPP_INLINE_VISIBILITY
2592  ~unique_ptr() { reset(); }
2593
2594  _LIBCPP_INLINE_VISIBILITY
2595  unique_ptr& operator=(nullptr_t) _NOEXCEPT {
2596    reset();
2597    return *this;
2598  }
2599
2600  _LIBCPP_INLINE_VISIBILITY
2601  typename add_lvalue_reference<_Tp>::type
2602  operator*() const {
2603    return *__ptr_.first();
2604  }
2605  _LIBCPP_INLINE_VISIBILITY
2606  pointer operator->() const _NOEXCEPT {
2607    return __ptr_.first();
2608  }
2609  _LIBCPP_INLINE_VISIBILITY
2610  pointer get() const _NOEXCEPT {
2611    return __ptr_.first();
2612  }
2613  _LIBCPP_INLINE_VISIBILITY
2614  deleter_type& get_deleter() _NOEXCEPT {
2615    return __ptr_.second();
2616  }
2617  _LIBCPP_INLINE_VISIBILITY
2618  const deleter_type& get_deleter() const _NOEXCEPT {
2619    return __ptr_.second();
2620  }
2621  _LIBCPP_INLINE_VISIBILITY
2622  _LIBCPP_EXPLICIT operator bool() const _NOEXCEPT {
2623    return __ptr_.first() != nullptr;
2624  }
2625
2626  _LIBCPP_INLINE_VISIBILITY
2627  pointer release() _NOEXCEPT {
2628    pointer __t = __ptr_.first();
2629    __ptr_.first() = pointer();
2630    return __t;
2631  }
2632
2633  _LIBCPP_INLINE_VISIBILITY
2634  void reset(pointer __p = pointer()) _NOEXCEPT {
2635    pointer __tmp = __ptr_.first();
2636    __ptr_.first() = __p;
2637    if (__tmp)
2638      __ptr_.second()(__tmp);
2639  }
2640
2641  _LIBCPP_INLINE_VISIBILITY
2642  void swap(unique_ptr& __u) _NOEXCEPT {
2643    __ptr_.swap(__u.__ptr_);
2644  }
2645};
2646
2647
2648template <class _Tp, class _Dp>
2649class _LIBCPP_TEMPLATE_VIS unique_ptr<_Tp[], _Dp> {
2650public:
2651  typedef _Tp element_type;
2652  typedef _Dp deleter_type;
2653  typedef typename __pointer_type<_Tp, deleter_type>::type pointer;
2654
2655private:
2656  __compressed_pair<pointer, deleter_type> __ptr_;
2657
2658  template <class _From>
2659  struct _CheckArrayPointerConversion : is_same<_From, pointer> {};
2660
2661  template <class _FromElem>
2662  struct _CheckArrayPointerConversion<_FromElem*>
2663      : integral_constant<bool,
2664          is_same<_FromElem*, pointer>::value ||
2665            (is_same<pointer, element_type*>::value &&
2666             is_convertible<_FromElem(*)[], element_type(*)[]>::value)
2667      >
2668  {};
2669
2670#ifndef _LIBCPP_CXX03_LANG
2671  typedef __unique_ptr_deleter_sfinae<_Dp> _DeleterSFINAE;
2672
2673  template <bool _Dummy>
2674  using _LValRefType =
2675      typename __dependent_type<_DeleterSFINAE, _Dummy>::__lval_ref_type;
2676
2677  template <bool _Dummy>
2678  using _GoodRValRefType =
2679      typename __dependent_type<_DeleterSFINAE, _Dummy>::__good_rval_ref_type;
2680
2681  template <bool _Dummy>
2682  using _BadRValRefType =
2683      typename __dependent_type<_DeleterSFINAE, _Dummy>::__bad_rval_ref_type;
2684
2685  template <bool _Dummy, class _Deleter = typename __dependent_type<
2686                             __identity<deleter_type>, _Dummy>::type>
2687  using _EnableIfDeleterDefaultConstructible =
2688      typename enable_if<is_default_constructible<_Deleter>::value &&
2689                         !is_pointer<_Deleter>::value>::type;
2690
2691  template <class _ArgType>
2692  using _EnableIfDeleterConstructible =
2693      typename enable_if<is_constructible<deleter_type, _ArgType>::value>::type;
2694
2695  template <class _Pp>
2696  using _EnableIfPointerConvertible = typename enable_if<
2697      _CheckArrayPointerConversion<_Pp>::value
2698  >::type;
2699
2700  template <class _UPtr, class _Up,
2701        class _ElemT = typename _UPtr::element_type>
2702  using _EnableIfMoveConvertible = typename enable_if<
2703      is_array<_Up>::value &&
2704      is_same<pointer, element_type*>::value &&
2705      is_same<typename _UPtr::pointer, _ElemT*>::value &&
2706      is_convertible<_ElemT(*)[], element_type(*)[]>::value
2707    >::type;
2708
2709  template <class _UDel>
2710  using _EnableIfDeleterConvertible = typename enable_if<
2711      (is_reference<_Dp>::value && is_same<_Dp, _UDel>::value) ||
2712      (!is_reference<_Dp>::value && is_convertible<_UDel, _Dp>::value)
2713    >::type;
2714
2715  template <class _UDel>
2716  using _EnableIfDeleterAssignable = typename enable_if<
2717      is_assignable<_Dp&, _UDel&&>::value
2718    >::type;
2719
2720public:
2721  template <bool _Dummy = true,
2722            class = _EnableIfDeleterDefaultConstructible<_Dummy>>
2723  _LIBCPP_INLINE_VISIBILITY
2724  constexpr unique_ptr() noexcept : __ptr_(pointer()) {}
2725
2726  template <bool _Dummy = true,
2727            class = _EnableIfDeleterDefaultConstructible<_Dummy>>
2728  _LIBCPP_INLINE_VISIBILITY
2729  constexpr unique_ptr(nullptr_t) noexcept : __ptr_(pointer()) {}
2730
2731  template <class _Pp, bool _Dummy = true,
2732            class = _EnableIfDeleterDefaultConstructible<_Dummy>,
2733            class = _EnableIfPointerConvertible<_Pp>>
2734  _LIBCPP_INLINE_VISIBILITY
2735  explicit unique_ptr(_Pp __p) noexcept
2736      : __ptr_(__p) {}
2737
2738  template <class _Pp, bool _Dummy = true,
2739            class = _EnableIfDeleterConstructible<_LValRefType<_Dummy>>,
2740            class = _EnableIfPointerConvertible<_Pp>>
2741  _LIBCPP_INLINE_VISIBILITY
2742  unique_ptr(_Pp __p, _LValRefType<_Dummy> __d) noexcept
2743      : __ptr_(__p, __d) {}
2744
2745  template <bool _Dummy = true,
2746            class = _EnableIfDeleterConstructible<_LValRefType<_Dummy>>>
2747  _LIBCPP_INLINE_VISIBILITY
2748  unique_ptr(nullptr_t, _LValRefType<_Dummy> __d) noexcept
2749      : __ptr_(nullptr, __d) {}
2750
2751  template <class _Pp, bool _Dummy = true,
2752            class = _EnableIfDeleterConstructible<_GoodRValRefType<_Dummy>>,
2753            class = _EnableIfPointerConvertible<_Pp>>
2754  _LIBCPP_INLINE_VISIBILITY
2755  unique_ptr(_Pp __p, _GoodRValRefType<_Dummy> __d) noexcept
2756      : __ptr_(__p, _VSTD::move(__d)) {
2757    static_assert(!is_reference<deleter_type>::value,
2758                  "rvalue deleter bound to reference");
2759  }
2760
2761  template <bool _Dummy = true,
2762            class = _EnableIfDeleterConstructible<_GoodRValRefType<_Dummy>>>
2763  _LIBCPP_INLINE_VISIBILITY
2764  unique_ptr(nullptr_t, _GoodRValRefType<_Dummy> __d) noexcept
2765      : __ptr_(nullptr, _VSTD::move(__d)) {
2766    static_assert(!is_reference<deleter_type>::value,
2767                  "rvalue deleter bound to reference");
2768  }
2769
2770  template <class _Pp, bool _Dummy = true,
2771            class = _EnableIfDeleterConstructible<_BadRValRefType<_Dummy>>,
2772            class = _EnableIfPointerConvertible<_Pp>>
2773  _LIBCPP_INLINE_VISIBILITY
2774  unique_ptr(_Pp __p, _BadRValRefType<_Dummy> __d) = delete;
2775
2776  _LIBCPP_INLINE_VISIBILITY
2777  unique_ptr(unique_ptr&& __u) noexcept
2778      : __ptr_(__u.release(), _VSTD::forward<deleter_type>(__u.get_deleter())) {
2779  }
2780
2781  _LIBCPP_INLINE_VISIBILITY
2782  unique_ptr& operator=(unique_ptr&& __u) noexcept {
2783    reset(__u.release());
2784    __ptr_.second() = _VSTD::forward<deleter_type>(__u.get_deleter());
2785    return *this;
2786  }
2787
2788  template <class _Up, class _Ep,
2789      class = _EnableIfMoveConvertible<unique_ptr<_Up, _Ep>, _Up>,
2790      class = _EnableIfDeleterConvertible<_Ep>
2791  >
2792  _LIBCPP_INLINE_VISIBILITY
2793  unique_ptr(unique_ptr<_Up, _Ep>&& __u) noexcept
2794      : __ptr_(__u.release(), _VSTD::forward<_Ep>(__u.get_deleter())) {
2795  }
2796
2797  template <class _Up, class _Ep,
2798      class = _EnableIfMoveConvertible<unique_ptr<_Up, _Ep>, _Up>,
2799      class = _EnableIfDeleterAssignable<_Ep>
2800  >
2801  _LIBCPP_INLINE_VISIBILITY
2802  unique_ptr&
2803  operator=(unique_ptr<_Up, _Ep>&& __u) noexcept {
2804    reset(__u.release());
2805    __ptr_.second() = _VSTD::forward<_Ep>(__u.get_deleter());
2806    return *this;
2807  }
2808
2809#else // _LIBCPP_CXX03_LANG
2810private:
2811  template <class _Up> explicit unique_ptr(_Up);
2812
2813  unique_ptr(unique_ptr&);
2814  template <class _Up> unique_ptr(unique_ptr<_Up>&);
2815
2816  unique_ptr& operator=(unique_ptr&);
2817  template <class _Up> unique_ptr& operator=(unique_ptr<_Up>&);
2818
2819  template <class _Up>
2820  unique_ptr(_Up __u,
2821             typename conditional<
2822                 is_reference<deleter_type>::value, deleter_type,
2823                 typename add_lvalue_reference<const deleter_type>::type>::type,
2824             typename enable_if<is_convertible<_Up, pointer>::value,
2825                                __nat>::type = __nat());
2826public:
2827  _LIBCPP_INLINE_VISIBILITY
2828  unique_ptr() : __ptr_(pointer()) {
2829    static_assert(!is_pointer<deleter_type>::value,
2830                  "unique_ptr constructed with null function pointer deleter");
2831  }
2832  _LIBCPP_INLINE_VISIBILITY
2833  unique_ptr(nullptr_t) : __ptr_(pointer()) {
2834    static_assert(!is_pointer<deleter_type>::value,
2835                  "unique_ptr constructed with null function pointer deleter");
2836  }
2837
2838  _LIBCPP_INLINE_VISIBILITY
2839  explicit unique_ptr(pointer __p) : __ptr_(__p) {
2840    static_assert(!is_pointer<deleter_type>::value,
2841                  "unique_ptr constructed with null function pointer deleter");
2842  }
2843
2844  _LIBCPP_INLINE_VISIBILITY
2845  unique_ptr(pointer __p, deleter_type __d)
2846      : __ptr_(__p, _VSTD::forward<deleter_type>(__d)) {}
2847
2848  _LIBCPP_INLINE_VISIBILITY
2849  unique_ptr(nullptr_t, deleter_type __d)
2850      : __ptr_(pointer(), _VSTD::forward<deleter_type>(__d)) {}
2851
2852  _LIBCPP_INLINE_VISIBILITY
2853  operator __rv<unique_ptr>() {
2854    return __rv<unique_ptr>(*this);
2855  }
2856
2857  _LIBCPP_INLINE_VISIBILITY
2858  unique_ptr(__rv<unique_ptr> __u)
2859      : __ptr_(__u->release(),
2860               _VSTD::forward<deleter_type>(__u->get_deleter())) {}
2861
2862  _LIBCPP_INLINE_VISIBILITY
2863  unique_ptr& operator=(__rv<unique_ptr> __u) {
2864    reset(__u->release());
2865    __ptr_.second() = _VSTD::forward<deleter_type>(__u->get_deleter());
2866    return *this;
2867  }
2868
2869#endif // _LIBCPP_CXX03_LANG
2870
2871public:
2872  _LIBCPP_INLINE_VISIBILITY
2873  ~unique_ptr() { reset(); }
2874
2875  _LIBCPP_INLINE_VISIBILITY
2876  unique_ptr& operator=(nullptr_t) _NOEXCEPT {
2877    reset();
2878    return *this;
2879  }
2880
2881  _LIBCPP_INLINE_VISIBILITY
2882  typename add_lvalue_reference<_Tp>::type
2883  operator[](size_t __i) const {
2884    return __ptr_.first()[__i];
2885  }
2886  _LIBCPP_INLINE_VISIBILITY
2887  pointer get() const _NOEXCEPT {
2888    return __ptr_.first();
2889  }
2890
2891  _LIBCPP_INLINE_VISIBILITY
2892  deleter_type& get_deleter() _NOEXCEPT {
2893    return __ptr_.second();
2894  }
2895
2896  _LIBCPP_INLINE_VISIBILITY
2897  const deleter_type& get_deleter() const _NOEXCEPT {
2898    return __ptr_.second();
2899  }
2900  _LIBCPP_INLINE_VISIBILITY
2901  _LIBCPP_EXPLICIT operator bool() const _NOEXCEPT {
2902    return __ptr_.first() != nullptr;
2903  }
2904
2905  _LIBCPP_INLINE_VISIBILITY
2906  pointer release() _NOEXCEPT {
2907    pointer __t = __ptr_.first();
2908    __ptr_.first() = pointer();
2909    return __t;
2910  }
2911
2912  template <class _Pp>
2913  _LIBCPP_INLINE_VISIBILITY
2914  typename enable_if<
2915      _CheckArrayPointerConversion<_Pp>::value
2916  >::type
2917  reset(_Pp __p) _NOEXCEPT {
2918    pointer __tmp = __ptr_.first();
2919    __ptr_.first() = __p;
2920    if (__tmp)
2921      __ptr_.second()(__tmp);
2922  }
2923
2924  _LIBCPP_INLINE_VISIBILITY
2925  void reset(nullptr_t = nullptr) _NOEXCEPT {
2926    pointer __tmp = __ptr_.first();
2927    __ptr_.first() = nullptr;
2928    if (__tmp)
2929      __ptr_.second()(__tmp);
2930  }
2931
2932  _LIBCPP_INLINE_VISIBILITY
2933  void swap(unique_ptr& __u) _NOEXCEPT {
2934    __ptr_.swap(__u.__ptr_);
2935  }
2936
2937};
2938
2939template <class _Tp, class _Dp>
2940inline _LIBCPP_INLINE_VISIBILITY
2941typename enable_if<
2942    __is_swappable<_Dp>::value,
2943    void
2944>::type
2945swap(unique_ptr<_Tp, _Dp>& __x, unique_ptr<_Tp, _Dp>& __y) _NOEXCEPT {__x.swap(__y);}
2946
2947template <class _T1, class _D1, class _T2, class _D2>
2948inline _LIBCPP_INLINE_VISIBILITY
2949bool
2950operator==(const unique_ptr<_T1, _D1>& __x, const unique_ptr<_T2, _D2>& __y) {return __x.get() == __y.get();}
2951
2952template <class _T1, class _D1, class _T2, class _D2>
2953inline _LIBCPP_INLINE_VISIBILITY
2954bool
2955operator!=(const unique_ptr<_T1, _D1>& __x, const unique_ptr<_T2, _D2>& __y) {return !(__x == __y);}
2956
2957template <class _T1, class _D1, class _T2, class _D2>
2958inline _LIBCPP_INLINE_VISIBILITY
2959bool
2960operator< (const unique_ptr<_T1, _D1>& __x, const unique_ptr<_T2, _D2>& __y)
2961{
2962    typedef typename unique_ptr<_T1, _D1>::pointer _P1;
2963    typedef typename unique_ptr<_T2, _D2>::pointer _P2;
2964    typedef typename common_type<_P1, _P2>::type _Vp;
2965    return less<_Vp>()(__x.get(), __y.get());
2966}
2967
2968template <class _T1, class _D1, class _T2, class _D2>
2969inline _LIBCPP_INLINE_VISIBILITY
2970bool
2971operator> (const unique_ptr<_T1, _D1>& __x, const unique_ptr<_T2, _D2>& __y) {return __y < __x;}
2972
2973template <class _T1, class _D1, class _T2, class _D2>
2974inline _LIBCPP_INLINE_VISIBILITY
2975bool
2976operator<=(const unique_ptr<_T1, _D1>& __x, const unique_ptr<_T2, _D2>& __y) {return !(__y < __x);}
2977
2978template <class _T1, class _D1, class _T2, class _D2>
2979inline _LIBCPP_INLINE_VISIBILITY
2980bool
2981operator>=(const unique_ptr<_T1, _D1>& __x, const unique_ptr<_T2, _D2>& __y) {return !(__x < __y);}
2982
2983template <class _T1, class _D1>
2984inline _LIBCPP_INLINE_VISIBILITY
2985bool
2986operator==(const unique_ptr<_T1, _D1>& __x, nullptr_t) _NOEXCEPT
2987{
2988    return !__x;
2989}
2990
2991template <class _T1, class _D1>
2992inline _LIBCPP_INLINE_VISIBILITY
2993bool
2994operator==(nullptr_t, const unique_ptr<_T1, _D1>& __x) _NOEXCEPT
2995{
2996    return !__x;
2997}
2998
2999template <class _T1, class _D1>
3000inline _LIBCPP_INLINE_VISIBILITY
3001bool
3002operator!=(const unique_ptr<_T1, _D1>& __x, nullptr_t) _NOEXCEPT
3003{
3004    return static_cast<bool>(__x);
3005}
3006
3007template <class _T1, class _D1>
3008inline _LIBCPP_INLINE_VISIBILITY
3009bool
3010operator!=(nullptr_t, const unique_ptr<_T1, _D1>& __x) _NOEXCEPT
3011{
3012    return static_cast<bool>(__x);
3013}
3014
3015template <class _T1, class _D1>
3016inline _LIBCPP_INLINE_VISIBILITY
3017bool
3018operator<(const unique_ptr<_T1, _D1>& __x, nullptr_t)
3019{
3020    typedef typename unique_ptr<_T1, _D1>::pointer _P1;
3021    return less<_P1>()(__x.get(), nullptr);
3022}
3023
3024template <class _T1, class _D1>
3025inline _LIBCPP_INLINE_VISIBILITY
3026bool
3027operator<(nullptr_t, const unique_ptr<_T1, _D1>& __x)
3028{
3029    typedef typename unique_ptr<_T1, _D1>::pointer _P1;
3030    return less<_P1>()(nullptr, __x.get());
3031}
3032
3033template <class _T1, class _D1>
3034inline _LIBCPP_INLINE_VISIBILITY
3035bool
3036operator>(const unique_ptr<_T1, _D1>& __x, nullptr_t)
3037{
3038    return nullptr < __x;
3039}
3040
3041template <class _T1, class _D1>
3042inline _LIBCPP_INLINE_VISIBILITY
3043bool
3044operator>(nullptr_t, const unique_ptr<_T1, _D1>& __x)
3045{
3046    return __x < nullptr;
3047}
3048
3049template <class _T1, class _D1>
3050inline _LIBCPP_INLINE_VISIBILITY
3051bool
3052operator<=(const unique_ptr<_T1, _D1>& __x, nullptr_t)
3053{
3054    return !(nullptr < __x);
3055}
3056
3057template <class _T1, class _D1>
3058inline _LIBCPP_INLINE_VISIBILITY
3059bool
3060operator<=(nullptr_t, const unique_ptr<_T1, _D1>& __x)
3061{
3062    return !(__x < nullptr);
3063}
3064
3065template <class _T1, class _D1>
3066inline _LIBCPP_INLINE_VISIBILITY
3067bool
3068operator>=(const unique_ptr<_T1, _D1>& __x, nullptr_t)
3069{
3070    return !(__x < nullptr);
3071}
3072
3073template <class _T1, class _D1>
3074inline _LIBCPP_INLINE_VISIBILITY
3075bool
3076operator>=(nullptr_t, const unique_ptr<_T1, _D1>& __x)
3077{
3078    return !(nullptr < __x);
3079}
3080
3081#ifdef _LIBCPP_HAS_NO_RVALUE_REFERENCES
3082
3083template <class _Tp, class _Dp>
3084inline _LIBCPP_INLINE_VISIBILITY
3085unique_ptr<_Tp, _Dp>
3086move(unique_ptr<_Tp, _Dp>& __t)
3087{
3088    return unique_ptr<_Tp, _Dp>(__rv<unique_ptr<_Tp, _Dp> >(__t));
3089}
3090
3091#endif
3092
3093#if _LIBCPP_STD_VER > 11
3094
3095template<class _Tp>
3096struct __unique_if
3097{
3098    typedef unique_ptr<_Tp> __unique_single;
3099};
3100
3101template<class _Tp>
3102struct __unique_if<_Tp[]>
3103{
3104    typedef unique_ptr<_Tp[]> __unique_array_unknown_bound;
3105};
3106
3107template<class _Tp, size_t _Np>
3108struct __unique_if<_Tp[_Np]>
3109{
3110    typedef void __unique_array_known_bound;
3111};
3112
3113template<class _Tp, class... _Args>
3114inline _LIBCPP_INLINE_VISIBILITY
3115typename __unique_if<_Tp>::__unique_single
3116make_unique(_Args&&... __args)
3117{
3118    return unique_ptr<_Tp>(new _Tp(_VSTD::forward<_Args>(__args)...));
3119}
3120
3121template<class _Tp>
3122inline _LIBCPP_INLINE_VISIBILITY
3123typename __unique_if<_Tp>::__unique_array_unknown_bound
3124make_unique(size_t __n)
3125{
3126    typedef typename remove_extent<_Tp>::type _Up;
3127    return unique_ptr<_Tp>(new _Up[__n]());
3128}
3129
3130template<class _Tp, class... _Args>
3131    typename __unique_if<_Tp>::__unique_array_known_bound
3132    make_unique(_Args&&...) = delete;
3133
3134#endif  // _LIBCPP_STD_VER > 11
3135
3136template <class _Tp, class _Dp>
3137#ifdef _LIBCPP_CXX03_LANG
3138struct _LIBCPP_TEMPLATE_VIS hash<unique_ptr<_Tp, _Dp> >
3139#else
3140struct _LIBCPP_TEMPLATE_VIS hash<__enable_hash_helper<
3141    unique_ptr<_Tp, _Dp>, typename unique_ptr<_Tp, _Dp>::pointer>>
3142#endif
3143{
3144    typedef unique_ptr<_Tp, _Dp> argument_type;
3145    typedef size_t               result_type;
3146    _LIBCPP_INLINE_VISIBILITY
3147    result_type operator()(const argument_type& __ptr) const
3148    {
3149        typedef typename argument_type::pointer pointer;
3150        return hash<pointer>()(__ptr.get());
3151    }
3152};
3153
3154struct __destruct_n
3155{
3156private:
3157    size_t __size_;
3158
3159    template <class _Tp>
3160    _LIBCPP_INLINE_VISIBILITY void __process(_Tp* __p, false_type) _NOEXCEPT
3161        {for (size_t __i = 0; __i < __size_; ++__i, ++__p) __p->~_Tp();}
3162
3163    template <class _Tp>
3164    _LIBCPP_INLINE_VISIBILITY void __process(_Tp*, true_type) _NOEXCEPT
3165        {}
3166
3167    _LIBCPP_INLINE_VISIBILITY void __incr(false_type) _NOEXCEPT
3168        {++__size_;}
3169    _LIBCPP_INLINE_VISIBILITY void __incr(true_type) _NOEXCEPT
3170        {}
3171
3172    _LIBCPP_INLINE_VISIBILITY void __set(size_t __s, false_type) _NOEXCEPT
3173        {__size_ = __s;}
3174    _LIBCPP_INLINE_VISIBILITY void __set(size_t, true_type) _NOEXCEPT
3175        {}
3176public:
3177    _LIBCPP_INLINE_VISIBILITY explicit __destruct_n(size_t __s) _NOEXCEPT
3178        : __size_(__s) {}
3179
3180    template <class _Tp>
3181    _LIBCPP_INLINE_VISIBILITY void __incr(_Tp*) _NOEXCEPT
3182        {__incr(integral_constant<bool, is_trivially_destructible<_Tp>::value>());}
3183
3184    template <class _Tp>
3185    _LIBCPP_INLINE_VISIBILITY void __set(size_t __s, _Tp*) _NOEXCEPT
3186        {__set(__s, integral_constant<bool, is_trivially_destructible<_Tp>::value>());}
3187
3188    template <class _Tp>
3189    _LIBCPP_INLINE_VISIBILITY void operator()(_Tp* __p) _NOEXCEPT
3190        {__process(__p, integral_constant<bool, is_trivially_destructible<_Tp>::value>());}
3191};
3192
3193template <class _Alloc>
3194class __allocator_destructor
3195{
3196    typedef allocator_traits<_Alloc> __alloc_traits;
3197public:
3198    typedef typename __alloc_traits::pointer pointer;
3199    typedef typename __alloc_traits::size_type size_type;
3200private:
3201    _Alloc& __alloc_;
3202    size_type __s_;
3203public:
3204    _LIBCPP_INLINE_VISIBILITY __allocator_destructor(_Alloc& __a, size_type __s)
3205             _NOEXCEPT
3206        : __alloc_(__a), __s_(__s) {}
3207    _LIBCPP_INLINE_VISIBILITY
3208    void operator()(pointer __p) _NOEXCEPT
3209        {__alloc_traits::deallocate(__alloc_, __p, __s_);}
3210};
3211
3212template <class _InputIterator, class _ForwardIterator>
3213_ForwardIterator
3214uninitialized_copy(_InputIterator __f, _InputIterator __l, _ForwardIterator __r)
3215{
3216    typedef typename iterator_traits<_ForwardIterator>::value_type value_type;
3217#ifndef _LIBCPP_NO_EXCEPTIONS
3218    _ForwardIterator __s = __r;
3219    try
3220    {
3221#endif
3222        for (; __f != __l; ++__f, (void) ++__r)
3223            ::new (static_cast<void*>(_VSTD::addressof(*__r))) value_type(*__f);
3224#ifndef _LIBCPP_NO_EXCEPTIONS
3225    }
3226    catch (...)
3227    {
3228        for (; __s != __r; ++__s)
3229            __s->~value_type();
3230        throw;
3231    }
3232#endif
3233    return __r;
3234}
3235
3236template <class _InputIterator, class _Size, class _ForwardIterator>
3237_ForwardIterator
3238uninitialized_copy_n(_InputIterator __f, _Size __n, _ForwardIterator __r)
3239{
3240    typedef typename iterator_traits<_ForwardIterator>::value_type value_type;
3241#ifndef _LIBCPP_NO_EXCEPTIONS
3242    _ForwardIterator __s = __r;
3243    try
3244    {
3245#endif
3246        for (; __n > 0; ++__f, (void) ++__r, (void) --__n)
3247            ::new (static_cast<void*>(_VSTD::addressof(*__r))) value_type(*__f);
3248#ifndef _LIBCPP_NO_EXCEPTIONS
3249    }
3250    catch (...)
3251    {
3252        for (; __s != __r; ++__s)
3253            __s->~value_type();
3254        throw;
3255    }
3256#endif
3257    return __r;
3258}
3259
3260template <class _ForwardIterator, class _Tp>
3261void
3262uninitialized_fill(_ForwardIterator __f, _ForwardIterator __l, const _Tp& __x)
3263{
3264    typedef typename iterator_traits<_ForwardIterator>::value_type value_type;
3265#ifndef _LIBCPP_NO_EXCEPTIONS
3266    _ForwardIterator __s = __f;
3267    try
3268    {
3269#endif
3270        for (; __f != __l; ++__f)
3271            ::new (static_cast<void*>(_VSTD::addressof(*__f))) value_type(__x);
3272#ifndef _LIBCPP_NO_EXCEPTIONS
3273    }
3274    catch (...)
3275    {
3276        for (; __s != __f; ++__s)
3277            __s->~value_type();
3278        throw;
3279    }
3280#endif
3281}
3282
3283template <class _ForwardIterator, class _Size, class _Tp>
3284_ForwardIterator
3285uninitialized_fill_n(_ForwardIterator __f, _Size __n, const _Tp& __x)
3286{
3287    typedef typename iterator_traits<_ForwardIterator>::value_type value_type;
3288#ifndef _LIBCPP_NO_EXCEPTIONS
3289    _ForwardIterator __s = __f;
3290    try
3291    {
3292#endif
3293        for (; __n > 0; ++__f, (void) --__n)
3294            ::new (static_cast<void*>(_VSTD::addressof(*__f))) value_type(__x);
3295#ifndef _LIBCPP_NO_EXCEPTIONS
3296    }
3297    catch (...)
3298    {
3299        for (; __s != __f; ++__s)
3300            __s->~value_type();
3301        throw;
3302    }
3303#endif
3304    return __f;
3305}
3306
3307#if _LIBCPP_STD_VER > 14
3308
3309template <class _Tp>
3310inline _LIBCPP_INLINE_VISIBILITY
3311void destroy_at(_Tp* __loc) {
3312    _LIBCPP_ASSERT(__loc, "null pointer given to destroy_at");
3313    __loc->~_Tp();
3314}
3315
3316template <class _ForwardIterator>
3317inline _LIBCPP_INLINE_VISIBILITY
3318void destroy(_ForwardIterator __first, _ForwardIterator __last) {
3319    for (; __first != __last; ++__first)
3320        _VSTD::destroy_at(_VSTD::addressof(*__first));
3321}
3322
3323template <class _ForwardIterator, class _Size>
3324inline _LIBCPP_INLINE_VISIBILITY
3325_ForwardIterator destroy_n(_ForwardIterator __first, _Size __n) {
3326    for (; __n > 0; (void)++__first, --__n)
3327        _VSTD::destroy_at(_VSTD::addressof(*__first));
3328    return __first;
3329}
3330
3331template <class _ForwardIterator>
3332inline _LIBCPP_INLINE_VISIBILITY
3333void uninitialized_default_construct(_ForwardIterator __first, _ForwardIterator __last) {
3334    using _Vt = typename iterator_traits<_ForwardIterator>::value_type;
3335    auto __idx = __first;
3336#ifndef _LIBCPP_NO_EXCEPTIONS
3337    try {
3338#endif
3339    for (; __idx != __last; ++__idx)
3340        ::new((void*)_VSTD::addressof(*__idx)) _Vt;
3341#ifndef _LIBCPP_NO_EXCEPTIONS
3342    } catch (...) {
3343        _VSTD::destroy(__first, __idx);
3344        throw;
3345    }
3346#endif
3347}
3348
3349template <class _ForwardIterator, class _Size>
3350inline _LIBCPP_INLINE_VISIBILITY
3351_ForwardIterator uninitialized_default_construct_n(_ForwardIterator __first, _Size __n) {
3352    using _Vt = typename iterator_traits<_ForwardIterator>::value_type;
3353    auto __idx = __first;
3354#ifndef _LIBCPP_NO_EXCEPTIONS
3355    try {
3356#endif
3357    for (; __n > 0; (void)++__idx, --__n)
3358        ::new((void*)_VSTD::addressof(*__idx)) _Vt;
3359    return __idx;
3360#ifndef _LIBCPP_NO_EXCEPTIONS
3361    } catch (...) {
3362        _VSTD::destroy(__first, __idx);
3363        throw;
3364    }
3365#endif
3366}
3367
3368
3369template <class _ForwardIterator>
3370inline _LIBCPP_INLINE_VISIBILITY
3371void uninitialized_value_construct(_ForwardIterator __first, _ForwardIterator __last) {
3372    using _Vt = typename iterator_traits<_ForwardIterator>::value_type;
3373    auto __idx = __first;
3374#ifndef _LIBCPP_NO_EXCEPTIONS
3375    try {
3376#endif
3377    for (; __idx != __last; ++__idx)
3378        ::new((void*)_VSTD::addressof(*__idx)) _Vt();
3379#ifndef _LIBCPP_NO_EXCEPTIONS
3380    } catch (...) {
3381        _VSTD::destroy(__first, __idx);
3382        throw;
3383    }
3384#endif
3385}
3386
3387template <class _ForwardIterator, class _Size>
3388inline _LIBCPP_INLINE_VISIBILITY
3389_ForwardIterator uninitialized_value_construct_n(_ForwardIterator __first, _Size __n) {
3390    using _Vt = typename iterator_traits<_ForwardIterator>::value_type;
3391    auto __idx = __first;
3392#ifndef _LIBCPP_NO_EXCEPTIONS
3393    try {
3394#endif
3395    for (; __n > 0; (void)++__idx, --__n)
3396        ::new((void*)_VSTD::addressof(*__idx)) _Vt();
3397    return __idx;
3398#ifndef _LIBCPP_NO_EXCEPTIONS
3399    } catch (...) {
3400        _VSTD::destroy(__first, __idx);
3401        throw;
3402    }
3403#endif
3404}
3405
3406
3407template <class _InputIt, class _ForwardIt>
3408inline _LIBCPP_INLINE_VISIBILITY
3409_ForwardIt uninitialized_move(_InputIt __first, _InputIt __last, _ForwardIt __first_res) {
3410    using _Vt = typename iterator_traits<_ForwardIt>::value_type;
3411    auto __idx = __first_res;
3412#ifndef _LIBCPP_NO_EXCEPTIONS
3413    try {
3414#endif
3415    for (; __first != __last; (void)++__idx, ++__first)
3416        ::new((void*)_VSTD::addressof(*__idx)) _Vt(std::move(*__first));
3417    return __idx;
3418#ifndef _LIBCPP_NO_EXCEPTIONS
3419    } catch (...) {
3420        _VSTD::destroy(__first_res, __idx);
3421        throw;
3422    }
3423#endif
3424}
3425
3426template <class _InputIt, class _Size, class _ForwardIt>
3427inline _LIBCPP_INLINE_VISIBILITY
3428pair<_InputIt, _ForwardIt>
3429uninitialized_move_n(_InputIt __first, _Size __n, _ForwardIt __first_res) {
3430    using _Vt = typename iterator_traits<_ForwardIt>::value_type;
3431    auto __idx = __first_res;
3432#ifndef _LIBCPP_NO_EXCEPTIONS
3433    try {
3434#endif
3435    for (; __n > 0; ++__idx, (void)++__first, --__n)
3436        ::new((void*)_VSTD::addressof(*__idx)) _Vt(std::move(*__first));
3437    return {__first, __idx};
3438#ifndef _LIBCPP_NO_EXCEPTIONS
3439    } catch (...) {
3440        _VSTD::destroy(__first_res, __idx);
3441        throw;
3442    }
3443#endif
3444}
3445
3446
3447#endif // _LIBCPP_STD_VER > 14
3448
3449// NOTE: Relaxed and acq/rel atomics (for increment and decrement respectively)
3450// should be sufficient for thread safety.
3451// See https://bugs.llvm.org/show_bug.cgi?id=22803
3452#if defined(__clang__) && __has_builtin(__atomic_add_fetch)          \
3453                       && defined(__ATOMIC_RELAXED)                  \
3454                       && defined(__ATOMIC_ACQ_REL)
3455#   define _LIBCPP_HAS_BUILTIN_ATOMIC_SUPPORT
3456#elif !defined(__clang__) && defined(_GNUC_VER) && _GNUC_VER >= 407
3457#   define _LIBCPP_HAS_BUILTIN_ATOMIC_SUPPORT
3458#endif
3459
3460template <class _Tp>
3461inline _LIBCPP_INLINE_VISIBILITY _Tp
3462__libcpp_atomic_refcount_increment(_Tp& __t) _NOEXCEPT
3463{
3464#if defined(_LIBCPP_HAS_BUILTIN_ATOMIC_SUPPORT) && !defined(_LIBCPP_HAS_NO_THREADS)
3465    return __atomic_add_fetch(&__t, 1, __ATOMIC_RELAXED);
3466#else
3467    return __t += 1;
3468#endif
3469}
3470
3471template <class _Tp>
3472inline _LIBCPP_INLINE_VISIBILITY _Tp
3473__libcpp_atomic_refcount_decrement(_Tp& __t) _NOEXCEPT
3474{
3475#if defined(_LIBCPP_HAS_BUILTIN_ATOMIC_SUPPORT) && !defined(_LIBCPP_HAS_NO_THREADS)
3476    return __atomic_add_fetch(&__t, -1, __ATOMIC_ACQ_REL);
3477#else
3478    return __t -= 1;
3479#endif
3480}
3481
3482class _LIBCPP_EXCEPTION_ABI bad_weak_ptr
3483    : public std::exception
3484{
3485public:
3486    virtual ~bad_weak_ptr() _NOEXCEPT;
3487    virtual const char* what() const  _NOEXCEPT;
3488};
3489
3490_LIBCPP_NORETURN inline _LIBCPP_INLINE_VISIBILITY
3491void __throw_bad_weak_ptr()
3492{
3493#ifndef _LIBCPP_NO_EXCEPTIONS
3494    throw bad_weak_ptr();
3495#else
3496    _VSTD::abort();
3497#endif
3498}
3499
3500template<class _Tp> class _LIBCPP_TEMPLATE_VIS weak_ptr;
3501
3502class _LIBCPP_TYPE_VIS __shared_count
3503{
3504    __shared_count(const __shared_count&);
3505    __shared_count& operator=(const __shared_count&);
3506
3507protected:
3508    long __shared_owners_;
3509    virtual ~__shared_count();
3510private:
3511    virtual void __on_zero_shared() _NOEXCEPT = 0;
3512
3513public:
3514    _LIBCPP_INLINE_VISIBILITY
3515    explicit __shared_count(long __refs = 0) _NOEXCEPT
3516        : __shared_owners_(__refs) {}
3517
3518#if defined(_LIBCPP_BUILDING_LIBRARY) && \
3519    defined(_LIBCPP_DEPRECATED_ABI_LEGACY_LIBRARY_DEFINITIONS_FOR_INLINE_FUNCTIONS)
3520    void __add_shared() _NOEXCEPT;
3521    bool __release_shared() _NOEXCEPT;
3522#else
3523    _LIBCPP_INLINE_VISIBILITY
3524    void __add_shared() _NOEXCEPT {
3525      __libcpp_atomic_refcount_increment(__shared_owners_);
3526    }
3527    _LIBCPP_INLINE_VISIBILITY
3528    bool __release_shared() _NOEXCEPT {
3529      if (__libcpp_atomic_refcount_decrement(__shared_owners_) == -1) {
3530        __on_zero_shared();
3531        return true;
3532      }
3533      return false;
3534    }
3535#endif
3536    _LIBCPP_INLINE_VISIBILITY
3537    long use_count() const _NOEXCEPT {
3538        return __libcpp_relaxed_load(&__shared_owners_) + 1;
3539    }
3540};
3541
3542class _LIBCPP_TYPE_VIS __shared_weak_count
3543    : private __shared_count
3544{
3545    long __shared_weak_owners_;
3546
3547public:
3548    _LIBCPP_INLINE_VISIBILITY
3549    explicit __shared_weak_count(long __refs = 0) _NOEXCEPT
3550        : __shared_count(__refs),
3551          __shared_weak_owners_(__refs) {}
3552protected:
3553    virtual ~__shared_weak_count();
3554
3555public:
3556#if defined(_LIBCPP_BUILDING_LIBRARY) && \
3557    defined(_LIBCPP_DEPRECATED_ABI_LEGACY_LIBRARY_DEFINITIONS_FOR_INLINE_FUNCTIONS)
3558    void __add_shared() _NOEXCEPT;
3559    void __add_weak() _NOEXCEPT;
3560    void __release_shared() _NOEXCEPT;
3561#else
3562    _LIBCPP_INLINE_VISIBILITY
3563    void __add_shared() _NOEXCEPT {
3564      __shared_count::__add_shared();
3565    }
3566    _LIBCPP_INLINE_VISIBILITY
3567    void __add_weak() _NOEXCEPT {
3568      __libcpp_atomic_refcount_increment(__shared_weak_owners_);
3569    }
3570    _LIBCPP_INLINE_VISIBILITY
3571    void __release_shared() _NOEXCEPT {
3572      if (__shared_count::__release_shared())
3573        __release_weak();
3574    }
3575#endif
3576    void __release_weak() _NOEXCEPT;
3577    _LIBCPP_INLINE_VISIBILITY
3578    long use_count() const _NOEXCEPT {return __shared_count::use_count();}
3579    __shared_weak_count* lock() _NOEXCEPT;
3580
3581    // Define the function out only if we build static libc++ without RTTI.
3582    // Otherwise we may break clients who need to compile their projects with
3583    // -fno-rtti and yet link against a libc++.dylib compiled
3584    // without -fno-rtti.
3585#if !defined(_LIBCPP_NO_RTTI) || !defined(_LIBCPP_BUILD_STATIC)
3586    virtual const void* __get_deleter(const type_info&) const _NOEXCEPT;
3587#endif
3588private:
3589    virtual void __on_zero_shared_weak() _NOEXCEPT = 0;
3590};
3591
3592template <class _Tp, class _Dp, class _Alloc>
3593class __shared_ptr_pointer
3594    : public __shared_weak_count
3595{
3596    __compressed_pair<__compressed_pair<_Tp, _Dp>, _Alloc> __data_;
3597public:
3598    _LIBCPP_INLINE_VISIBILITY
3599    __shared_ptr_pointer(_Tp __p, _Dp __d, _Alloc __a)
3600        :  __data_(__compressed_pair<_Tp, _Dp>(__p, _VSTD::move(__d)), _VSTD::move(__a)) {}
3601
3602#ifndef _LIBCPP_NO_RTTI
3603    virtual const void* __get_deleter(const type_info&) const _NOEXCEPT;
3604#endif
3605
3606private:
3607    virtual void __on_zero_shared() _NOEXCEPT;
3608    virtual void __on_zero_shared_weak() _NOEXCEPT;
3609};
3610
3611#ifndef _LIBCPP_NO_RTTI
3612
3613template <class _Tp, class _Dp, class _Alloc>
3614const void*
3615__shared_ptr_pointer<_Tp, _Dp, _Alloc>::__get_deleter(const type_info& __t) const _NOEXCEPT
3616{
3617    return __t == typeid(_Dp) ? _VSTD::addressof(__data_.first().second()) : nullptr;
3618}
3619
3620#endif  // _LIBCPP_NO_RTTI
3621
3622template <class _Tp, class _Dp, class _Alloc>
3623void
3624__shared_ptr_pointer<_Tp, _Dp, _Alloc>::__on_zero_shared() _NOEXCEPT
3625{
3626    __data_.first().second()(__data_.first().first());
3627    __data_.first().second().~_Dp();
3628}
3629
3630template <class _Tp, class _Dp, class _Alloc>
3631void
3632__shared_ptr_pointer<_Tp, _Dp, _Alloc>::__on_zero_shared_weak() _NOEXCEPT
3633{
3634    typedef typename __allocator_traits_rebind<_Alloc, __shared_ptr_pointer>::type _Al;
3635    typedef allocator_traits<_Al> _ATraits;
3636    typedef pointer_traits<typename _ATraits::pointer> _PTraits;
3637
3638    _Al __a(__data_.second());
3639    __data_.second().~_Alloc();
3640    __a.deallocate(_PTraits::pointer_to(*this), 1);
3641}
3642
3643template <class _Tp, class _Alloc>
3644class __shared_ptr_emplace
3645    : public __shared_weak_count
3646{
3647    __compressed_pair<_Alloc, _Tp> __data_;
3648public:
3649#ifndef _LIBCPP_HAS_NO_VARIADICS
3650
3651    _LIBCPP_INLINE_VISIBILITY
3652    __shared_ptr_emplace(_Alloc __a)
3653        :  __data_(_VSTD::move(__a)) {}
3654
3655    template <class ..._Args>
3656        _LIBCPP_INLINE_VISIBILITY
3657        __shared_ptr_emplace(_Alloc __a, _Args&& ...__args)
3658            :  __data_(piecewise_construct, _VSTD::forward_as_tuple(__a),
3659                   _VSTD::forward_as_tuple(_VSTD::forward<_Args>(__args)...)) {}
3660
3661#else  // _LIBCPP_HAS_NO_VARIADICS
3662
3663    _LIBCPP_INLINE_VISIBILITY
3664    __shared_ptr_emplace(_Alloc __a)
3665        :  __data_(__a) {}
3666
3667    template <class _A0>
3668        _LIBCPP_INLINE_VISIBILITY
3669        __shared_ptr_emplace(_Alloc __a, _A0& __a0)
3670            :  __data_(__a, _Tp(__a0)) {}
3671
3672    template <class _A0, class _A1>
3673        _LIBCPP_INLINE_VISIBILITY
3674        __shared_ptr_emplace(_Alloc __a, _A0& __a0, _A1& __a1)
3675            :  __data_(__a, _Tp(__a0, __a1)) {}
3676
3677    template <class _A0, class _A1, class _A2>
3678        _LIBCPP_INLINE_VISIBILITY
3679        __shared_ptr_emplace(_Alloc __a, _A0& __a0, _A1& __a1, _A2& __a2)
3680            :  __data_(__a, _Tp(__a0, __a1, __a2)) {}
3681
3682#endif  // _LIBCPP_HAS_NO_VARIADICS
3683
3684private:
3685    virtual void __on_zero_shared() _NOEXCEPT;
3686    virtual void __on_zero_shared_weak() _NOEXCEPT;
3687public:
3688    _LIBCPP_INLINE_VISIBILITY
3689    _Tp* get() _NOEXCEPT {return _VSTD::addressof(__data_.second());}
3690};
3691
3692template <class _Tp, class _Alloc>
3693void
3694__shared_ptr_emplace<_Tp, _Alloc>::__on_zero_shared() _NOEXCEPT
3695{
3696    __data_.second().~_Tp();
3697}
3698
3699template <class _Tp, class _Alloc>
3700void
3701__shared_ptr_emplace<_Tp, _Alloc>::__on_zero_shared_weak() _NOEXCEPT
3702{
3703    typedef typename __allocator_traits_rebind<_Alloc, __shared_ptr_emplace>::type _Al;
3704    typedef allocator_traits<_Al> _ATraits;
3705    typedef pointer_traits<typename _ATraits::pointer> _PTraits;
3706    _Al __a(__data_.first());
3707    __data_.first().~_Alloc();
3708    __a.deallocate(_PTraits::pointer_to(*this), 1);
3709}
3710
3711struct __shared_ptr_dummy_rebind_allocator_type;
3712template <>
3713class _LIBCPP_TEMPLATE_VIS allocator<__shared_ptr_dummy_rebind_allocator_type>
3714{
3715public:
3716    template <class _Other>
3717    struct rebind
3718    {
3719        typedef allocator<_Other> other;
3720    };
3721};
3722
3723template<class _Tp> class _LIBCPP_TEMPLATE_VIS enable_shared_from_this;
3724
3725template<class _Tp>
3726class _LIBCPP_TEMPLATE_VIS shared_ptr
3727{
3728public:
3729    typedef _Tp element_type;
3730
3731#if _LIBCPP_STD_VER > 14
3732    typedef weak_ptr<_Tp> weak_type;
3733#endif
3734private:
3735    element_type*      __ptr_;
3736    __shared_weak_count* __cntrl_;
3737
3738    struct __nat {int __for_bool_;};
3739public:
3740    _LIBCPP_INLINE_VISIBILITY
3741    _LIBCPP_CONSTEXPR shared_ptr() _NOEXCEPT;
3742    _LIBCPP_INLINE_VISIBILITY
3743    _LIBCPP_CONSTEXPR shared_ptr(nullptr_t) _NOEXCEPT;
3744    template<class _Yp>
3745        explicit shared_ptr(_Yp* __p,
3746                            typename enable_if<is_convertible<_Yp*, element_type*>::value, __nat>::type = __nat());
3747    template<class _Yp, class _Dp>
3748        shared_ptr(_Yp* __p, _Dp __d,
3749                   typename enable_if<is_convertible<_Yp*, element_type*>::value, __nat>::type = __nat());
3750    template<class _Yp, class _Dp, class _Alloc>
3751        shared_ptr(_Yp* __p, _Dp __d, _Alloc __a,
3752                   typename enable_if<is_convertible<_Yp*, element_type*>::value, __nat>::type = __nat());
3753    template <class _Dp> shared_ptr(nullptr_t __p, _Dp __d);
3754    template <class _Dp, class _Alloc> shared_ptr(nullptr_t __p, _Dp __d, _Alloc __a);
3755    template<class _Yp> _LIBCPP_INLINE_VISIBILITY shared_ptr(const shared_ptr<_Yp>& __r, element_type* __p) _NOEXCEPT;
3756    _LIBCPP_INLINE_VISIBILITY
3757    shared_ptr(const shared_ptr& __r) _NOEXCEPT;
3758    template<class _Yp>
3759        _LIBCPP_INLINE_VISIBILITY
3760        shared_ptr(const shared_ptr<_Yp>& __r,
3761                   typename enable_if<is_convertible<_Yp*, element_type*>::value, __nat>::type = __nat())
3762                       _NOEXCEPT;
3763#ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES
3764    _LIBCPP_INLINE_VISIBILITY
3765    shared_ptr(shared_ptr&& __r) _NOEXCEPT;
3766    template<class _Yp> _LIBCPP_INLINE_VISIBILITY  shared_ptr(shared_ptr<_Yp>&& __r,
3767                   typename enable_if<is_convertible<_Yp*, element_type*>::value, __nat>::type = __nat())
3768                       _NOEXCEPT;
3769#endif  // _LIBCPP_HAS_NO_RVALUE_REFERENCES
3770    template<class _Yp> explicit shared_ptr(const weak_ptr<_Yp>& __r,
3771                   typename enable_if<is_convertible<_Yp*, element_type*>::value, __nat>::type= __nat());
3772#if _LIBCPP_STD_VER <= 14 || defined(_LIBCPP_ENABLE_CXX17_REMOVED_AUTO_PTR)
3773#ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES
3774    template<class _Yp>
3775        shared_ptr(auto_ptr<_Yp>&& __r,
3776                   typename enable_if<is_convertible<_Yp*, element_type*>::value, __nat>::type = __nat());
3777#else
3778    template<class _Yp>
3779        shared_ptr(auto_ptr<_Yp> __r,
3780                   typename enable_if<is_convertible<_Yp*, element_type*>::value, __nat>::type = __nat());
3781#endif
3782#endif
3783#ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES
3784    template <class _Yp, class _Dp>
3785        shared_ptr(unique_ptr<_Yp, _Dp>&&,
3786                   typename enable_if
3787                   <
3788                       !is_lvalue_reference<_Dp>::value &&
3789                       !is_array<_Yp>::value &&
3790                       is_convertible<typename unique_ptr<_Yp, _Dp>::pointer, element_type*>::value,
3791                       __nat
3792                   >::type = __nat());
3793    template <class _Yp, class _Dp>
3794        shared_ptr(unique_ptr<_Yp, _Dp>&&,
3795                   typename enable_if
3796                   <
3797                       is_lvalue_reference<_Dp>::value &&
3798                       !is_array<_Yp>::value &&
3799                       is_convertible<typename unique_ptr<_Yp, _Dp>::pointer, element_type*>::value,
3800                       __nat
3801                   >::type = __nat());
3802#else  // _LIBCPP_HAS_NO_RVALUE_REFERENCES
3803    template <class _Yp, class _Dp>
3804        shared_ptr(unique_ptr<_Yp, _Dp>,
3805                   typename enable_if
3806                   <
3807                       !is_lvalue_reference<_Dp>::value &&
3808                       !is_array<_Yp>::value &&
3809                       is_convertible<typename unique_ptr<_Yp, _Dp>::pointer, element_type*>::value,
3810                       __nat
3811                   >::type = __nat());
3812    template <class _Yp, class _Dp>
3813        shared_ptr(unique_ptr<_Yp, _Dp>,
3814                   typename enable_if
3815                   <
3816                       is_lvalue_reference<_Dp>::value &&
3817                       !is_array<_Yp>::value &&
3818                       is_convertible<typename unique_ptr<_Yp, _Dp>::pointer, element_type*>::value,
3819                       __nat
3820                   >::type = __nat());
3821#endif  // _LIBCPP_HAS_NO_RVALUE_REFERENCES
3822
3823    ~shared_ptr();
3824
3825    _LIBCPP_INLINE_VISIBILITY
3826    shared_ptr& operator=(const shared_ptr& __r) _NOEXCEPT;
3827    template<class _Yp>
3828        typename enable_if
3829        <
3830            is_convertible<_Yp*, element_type*>::value,
3831            shared_ptr&
3832        >::type
3833        _LIBCPP_INLINE_VISIBILITY
3834        operator=(const shared_ptr<_Yp>& __r) _NOEXCEPT;
3835#ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES
3836    _LIBCPP_INLINE_VISIBILITY
3837    shared_ptr& operator=(shared_ptr&& __r) _NOEXCEPT;
3838    template<class _Yp>
3839        typename enable_if
3840        <
3841            is_convertible<_Yp*, element_type*>::value,
3842            shared_ptr<_Tp>&
3843        >::type
3844        _LIBCPP_INLINE_VISIBILITY
3845        operator=(shared_ptr<_Yp>&& __r);
3846#if _LIBCPP_STD_VER <= 14 || defined(_LIBCPP_ENABLE_CXX17_REMOVED_AUTO_PTR)
3847    template<class _Yp>
3848        _LIBCPP_INLINE_VISIBILITY
3849        typename enable_if
3850        <
3851            !is_array<_Yp>::value &&
3852            is_convertible<_Yp*, element_type*>::value,
3853            shared_ptr
3854        >::type&
3855        operator=(auto_ptr<_Yp>&& __r);
3856#endif
3857#else  // _LIBCPP_HAS_NO_RVALUE_REFERENCES
3858#if _LIBCPP_STD_VER <= 14 || defined(_LIBCPP_ENABLE_CXX17_REMOVED_AUTO_PTR)
3859    template<class _Yp>
3860        _LIBCPP_INLINE_VISIBILITY
3861        typename enable_if
3862        <
3863            !is_array<_Yp>::value &&
3864            is_convertible<_Yp*, element_type*>::value,
3865            shared_ptr&
3866        >::type
3867        operator=(auto_ptr<_Yp> __r);
3868#endif
3869#endif
3870    template <class _Yp, class _Dp>
3871        typename enable_if
3872        <
3873            !is_array<_Yp>::value &&
3874            is_convertible<typename unique_ptr<_Yp, _Dp>::pointer, element_type*>::value,
3875            shared_ptr&
3876        >::type
3877#ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES
3878        _LIBCPP_INLINE_VISIBILITY
3879        operator=(unique_ptr<_Yp, _Dp>&& __r);
3880#else  // _LIBCPP_HAS_NO_RVALUE_REFERENCES
3881        _LIBCPP_INLINE_VISIBILITY
3882        operator=(unique_ptr<_Yp, _Dp> __r);
3883#endif
3884
3885    _LIBCPP_INLINE_VISIBILITY
3886    void swap(shared_ptr& __r) _NOEXCEPT;
3887    _LIBCPP_INLINE_VISIBILITY
3888    void reset() _NOEXCEPT;
3889    template<class _Yp>
3890        typename enable_if
3891        <
3892            is_convertible<_Yp*, element_type*>::value,
3893            void
3894        >::type
3895        _LIBCPP_INLINE_VISIBILITY
3896        reset(_Yp* __p);
3897    template<class _Yp, class _Dp>
3898        typename enable_if
3899        <
3900            is_convertible<_Yp*, element_type*>::value,
3901            void
3902        >::type
3903        _LIBCPP_INLINE_VISIBILITY
3904        reset(_Yp* __p, _Dp __d);
3905    template<class _Yp, class _Dp, class _Alloc>
3906        typename enable_if
3907        <
3908            is_convertible<_Yp*, element_type*>::value,
3909            void
3910        >::type
3911        _LIBCPP_INLINE_VISIBILITY
3912        reset(_Yp* __p, _Dp __d, _Alloc __a);
3913
3914    _LIBCPP_INLINE_VISIBILITY
3915    element_type* get() const _NOEXCEPT {return __ptr_;}
3916    _LIBCPP_INLINE_VISIBILITY
3917    typename add_lvalue_reference<element_type>::type operator*() const _NOEXCEPT
3918        {return *__ptr_;}
3919    _LIBCPP_INLINE_VISIBILITY
3920    element_type* operator->() const _NOEXCEPT {return __ptr_;}
3921    _LIBCPP_INLINE_VISIBILITY
3922    long use_count() const _NOEXCEPT {return __cntrl_ ? __cntrl_->use_count() : 0;}
3923    _LIBCPP_INLINE_VISIBILITY
3924    bool unique() const _NOEXCEPT {return use_count() == 1;}
3925    _LIBCPP_INLINE_VISIBILITY
3926    _LIBCPP_EXPLICIT operator bool() const _NOEXCEPT {return get() != 0;}
3927    template <class _Up>
3928        _LIBCPP_INLINE_VISIBILITY
3929        bool owner_before(shared_ptr<_Up> const& __p) const _NOEXCEPT
3930        {return __cntrl_ < __p.__cntrl_;}
3931    template <class _Up>
3932        _LIBCPP_INLINE_VISIBILITY
3933        bool owner_before(weak_ptr<_Up> const& __p) const _NOEXCEPT
3934        {return __cntrl_ < __p.__cntrl_;}
3935    _LIBCPP_INLINE_VISIBILITY
3936    bool
3937    __owner_equivalent(const shared_ptr& __p) const
3938        {return __cntrl_ == __p.__cntrl_;}
3939
3940#ifndef _LIBCPP_NO_RTTI
3941    template <class _Dp>
3942        _LIBCPP_INLINE_VISIBILITY
3943        _Dp* __get_deleter() const _NOEXCEPT
3944            {return static_cast<_Dp*>(__cntrl_
3945                    ? const_cast<void *>(__cntrl_->__get_deleter(typeid(_Dp)))
3946                      : nullptr);}
3947#endif  // _LIBCPP_NO_RTTI
3948
3949#ifndef _LIBCPP_HAS_NO_VARIADICS
3950
3951    template<class ..._Args>
3952        static
3953        shared_ptr<_Tp>
3954        make_shared(_Args&& ...__args);
3955
3956    template<class _Alloc, class ..._Args>
3957        static
3958        shared_ptr<_Tp>
3959        allocate_shared(const _Alloc& __a, _Args&& ...__args);
3960
3961#else  // _LIBCPP_HAS_NO_VARIADICS
3962
3963    static shared_ptr<_Tp> make_shared();
3964
3965    template<class _A0>
3966        static shared_ptr<_Tp> make_shared(_A0&);
3967
3968    template<class _A0, class _A1>
3969        static shared_ptr<_Tp> make_shared(_A0&, _A1&);
3970
3971    template<class _A0, class _A1, class _A2>
3972        static shared_ptr<_Tp> make_shared(_A0&, _A1&, _A2&);
3973
3974    template<class _Alloc>
3975        static shared_ptr<_Tp>
3976        allocate_shared(const _Alloc& __a);
3977
3978    template<class _Alloc, class _A0>
3979        static shared_ptr<_Tp>
3980        allocate_shared(const _Alloc& __a, _A0& __a0);
3981
3982    template<class _Alloc, class _A0, class _A1>
3983        static shared_ptr<_Tp>
3984        allocate_shared(const _Alloc& __a, _A0& __a0, _A1& __a1);
3985
3986    template<class _Alloc, class _A0, class _A1, class _A2>
3987        static shared_ptr<_Tp>
3988        allocate_shared(const _Alloc& __a, _A0& __a0, _A1& __a1, _A2& __a2);
3989
3990#endif  // _LIBCPP_HAS_NO_VARIADICS
3991
3992private:
3993    template <class _Yp, bool = is_function<_Yp>::value>
3994        struct __shared_ptr_default_allocator
3995        {
3996            typedef allocator<_Yp> type;
3997        };
3998
3999    template <class _Yp>
4000        struct __shared_ptr_default_allocator<_Yp, true>
4001        {
4002            typedef allocator<__shared_ptr_dummy_rebind_allocator_type> type;
4003        };
4004
4005    template <class _Yp, class _OrigPtr>
4006        _LIBCPP_INLINE_VISIBILITY
4007        typename enable_if<is_convertible<_OrigPtr*,
4008                                          const enable_shared_from_this<_Yp>*
4009        >::value,
4010            void>::type
4011        __enable_weak_this(const enable_shared_from_this<_Yp>* __e,
4012                           _OrigPtr* __ptr) _NOEXCEPT
4013        {
4014            typedef typename remove_cv<_Yp>::type _RawYp;
4015            if (__e && __e->__weak_this_.expired())
4016            {
4017                __e->__weak_this_ = shared_ptr<_RawYp>(*this,
4018                    const_cast<_RawYp*>(static_cast<const _Yp*>(__ptr)));
4019            }
4020        }
4021
4022    _LIBCPP_INLINE_VISIBILITY void __enable_weak_this(...) _NOEXCEPT {}
4023
4024    template <class _Up> friend class _LIBCPP_TEMPLATE_VIS shared_ptr;
4025    template <class _Up> friend class _LIBCPP_TEMPLATE_VIS weak_ptr;
4026};
4027
4028
4029template<class _Tp>
4030inline
4031_LIBCPP_CONSTEXPR
4032shared_ptr<_Tp>::shared_ptr() _NOEXCEPT
4033    : __ptr_(0),
4034      __cntrl_(0)
4035{
4036}
4037
4038template<class _Tp>
4039inline
4040_LIBCPP_CONSTEXPR
4041shared_ptr<_Tp>::shared_ptr(nullptr_t) _NOEXCEPT
4042    : __ptr_(0),
4043      __cntrl_(0)
4044{
4045}
4046
4047template<class _Tp>
4048template<class _Yp>
4049shared_ptr<_Tp>::shared_ptr(_Yp* __p,
4050                            typename enable_if<is_convertible<_Yp*, element_type*>::value, __nat>::type)
4051    : __ptr_(__p)
4052{
4053    unique_ptr<_Yp> __hold(__p);
4054    typedef typename __shared_ptr_default_allocator<_Yp>::type _AllocT;
4055    typedef __shared_ptr_pointer<_Yp*, default_delete<_Yp>, _AllocT > _CntrlBlk;
4056    __cntrl_ = new _CntrlBlk(__p, default_delete<_Yp>(), _AllocT());
4057    __hold.release();
4058    __enable_weak_this(__p, __p);
4059}
4060
4061template<class _Tp>
4062template<class _Yp, class _Dp>
4063shared_ptr<_Tp>::shared_ptr(_Yp* __p, _Dp __d,
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 typename __shared_ptr_default_allocator<_Yp>::type _AllocT;
4072        typedef __shared_ptr_pointer<_Yp*, _Dp, _AllocT > _CntrlBlk;
4073        __cntrl_ = new _CntrlBlk(__p, __d, _AllocT());
4074        __enable_weak_this(__p, __p);
4075#ifndef _LIBCPP_NO_EXCEPTIONS
4076    }
4077    catch (...)
4078    {
4079        __d(__p);
4080        throw;
4081    }
4082#endif  // _LIBCPP_NO_EXCEPTIONS
4083}
4084
4085template<class _Tp>
4086template<class _Dp>
4087shared_ptr<_Tp>::shared_ptr(nullptr_t __p, _Dp __d)
4088    : __ptr_(0)
4089{
4090#ifndef _LIBCPP_NO_EXCEPTIONS
4091    try
4092    {
4093#endif  // _LIBCPP_NO_EXCEPTIONS
4094        typedef typename __shared_ptr_default_allocator<_Tp>::type _AllocT;
4095        typedef __shared_ptr_pointer<nullptr_t, _Dp, _AllocT > _CntrlBlk;
4096        __cntrl_ = new _CntrlBlk(__p, __d, _AllocT());
4097#ifndef _LIBCPP_NO_EXCEPTIONS
4098    }
4099    catch (...)
4100    {
4101        __d(__p);
4102        throw;
4103    }
4104#endif  // _LIBCPP_NO_EXCEPTIONS
4105}
4106
4107template<class _Tp>
4108template<class _Yp, class _Dp, class _Alloc>
4109shared_ptr<_Tp>::shared_ptr(_Yp* __p, _Dp __d, _Alloc __a,
4110                            typename enable_if<is_convertible<_Yp*, element_type*>::value, __nat>::type)
4111    : __ptr_(__p)
4112{
4113#ifndef _LIBCPP_NO_EXCEPTIONS
4114    try
4115    {
4116#endif  // _LIBCPP_NO_EXCEPTIONS
4117        typedef __shared_ptr_pointer<_Yp*, _Dp, _Alloc> _CntrlBlk;
4118        typedef typename __allocator_traits_rebind<_Alloc, _CntrlBlk>::type _A2;
4119        typedef __allocator_destructor<_A2> _D2;
4120        _A2 __a2(__a);
4121        unique_ptr<_CntrlBlk, _D2> __hold2(__a2.allocate(1), _D2(__a2, 1));
4122        ::new(static_cast<void*>(_VSTD::addressof(*__hold2.get())))
4123            _CntrlBlk(__p, __d, __a);
4124        __cntrl_ = _VSTD::addressof(*__hold2.release());
4125        __enable_weak_this(__p, __p);
4126#ifndef _LIBCPP_NO_EXCEPTIONS
4127    }
4128    catch (...)
4129    {
4130        __d(__p);
4131        throw;
4132    }
4133#endif  // _LIBCPP_NO_EXCEPTIONS
4134}
4135
4136template<class _Tp>
4137template<class _Dp, class _Alloc>
4138shared_ptr<_Tp>::shared_ptr(nullptr_t __p, _Dp __d, _Alloc __a)
4139    : __ptr_(0)
4140{
4141#ifndef _LIBCPP_NO_EXCEPTIONS
4142    try
4143    {
4144#endif  // _LIBCPP_NO_EXCEPTIONS
4145        typedef __shared_ptr_pointer<nullptr_t, _Dp, _Alloc> _CntrlBlk;
4146        typedef typename __allocator_traits_rebind<_Alloc, _CntrlBlk>::type _A2;
4147        typedef __allocator_destructor<_A2> _D2;
4148        _A2 __a2(__a);
4149        unique_ptr<_CntrlBlk, _D2> __hold2(__a2.allocate(1), _D2(__a2, 1));
4150        ::new(static_cast<void*>(_VSTD::addressof(*__hold2.get())))
4151            _CntrlBlk(__p, __d, __a);
4152        __cntrl_ = _VSTD::addressof(*__hold2.release());
4153#ifndef _LIBCPP_NO_EXCEPTIONS
4154    }
4155    catch (...)
4156    {
4157        __d(__p);
4158        throw;
4159    }
4160#endif  // _LIBCPP_NO_EXCEPTIONS
4161}
4162
4163template<class _Tp>
4164template<class _Yp>
4165inline
4166shared_ptr<_Tp>::shared_ptr(const shared_ptr<_Yp>& __r, element_type *__p) _NOEXCEPT
4167    : __ptr_(__p),
4168      __cntrl_(__r.__cntrl_)
4169{
4170    if (__cntrl_)
4171        __cntrl_->__add_shared();
4172}
4173
4174template<class _Tp>
4175inline
4176shared_ptr<_Tp>::shared_ptr(const shared_ptr& __r) _NOEXCEPT
4177    : __ptr_(__r.__ptr_),
4178      __cntrl_(__r.__cntrl_)
4179{
4180    if (__cntrl_)
4181        __cntrl_->__add_shared();
4182}
4183
4184template<class _Tp>
4185template<class _Yp>
4186inline
4187shared_ptr<_Tp>::shared_ptr(const shared_ptr<_Yp>& __r,
4188                            typename enable_if<is_convertible<_Yp*, element_type*>::value, __nat>::type)
4189         _NOEXCEPT
4190    : __ptr_(__r.__ptr_),
4191      __cntrl_(__r.__cntrl_)
4192{
4193    if (__cntrl_)
4194        __cntrl_->__add_shared();
4195}
4196
4197#ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES
4198
4199template<class _Tp>
4200inline
4201shared_ptr<_Tp>::shared_ptr(shared_ptr&& __r) _NOEXCEPT
4202    : __ptr_(__r.__ptr_),
4203      __cntrl_(__r.__cntrl_)
4204{
4205    __r.__ptr_ = 0;
4206    __r.__cntrl_ = 0;
4207}
4208
4209template<class _Tp>
4210template<class _Yp>
4211inline
4212shared_ptr<_Tp>::shared_ptr(shared_ptr<_Yp>&& __r,
4213                            typename enable_if<is_convertible<_Yp*, element_type*>::value, __nat>::type)
4214         _NOEXCEPT
4215    : __ptr_(__r.__ptr_),
4216      __cntrl_(__r.__cntrl_)
4217{
4218    __r.__ptr_ = 0;
4219    __r.__cntrl_ = 0;
4220}
4221
4222#endif  // _LIBCPP_HAS_NO_RVALUE_REFERENCES
4223
4224#if _LIBCPP_STD_VER <= 14 || defined(_LIBCPP_ENABLE_CXX17_REMOVED_AUTO_PTR)
4225template<class _Tp>
4226template<class _Yp>
4227#ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES
4228shared_ptr<_Tp>::shared_ptr(auto_ptr<_Yp>&& __r,
4229#else
4230shared_ptr<_Tp>::shared_ptr(auto_ptr<_Yp> __r,
4231#endif
4232                            typename enable_if<is_convertible<_Yp*, element_type*>::value, __nat>::type)
4233    : __ptr_(__r.get())
4234{
4235    typedef __shared_ptr_pointer<_Yp*, default_delete<_Yp>, allocator<_Yp> > _CntrlBlk;
4236    __cntrl_ = new _CntrlBlk(__r.get(), default_delete<_Yp>(), allocator<_Yp>());
4237    __enable_weak_this(__r.get(), __r.get());
4238    __r.release();
4239}
4240#endif
4241
4242template<class _Tp>
4243template <class _Yp, class _Dp>
4244#ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES
4245shared_ptr<_Tp>::shared_ptr(unique_ptr<_Yp, _Dp>&& __r,
4246#else
4247shared_ptr<_Tp>::shared_ptr(unique_ptr<_Yp, _Dp> __r,
4248#endif
4249                            typename enable_if
4250                            <
4251                                !is_lvalue_reference<_Dp>::value &&
4252                                !is_array<_Yp>::value &&
4253                                is_convertible<typename unique_ptr<_Yp, _Dp>::pointer, element_type*>::value,
4254                                __nat
4255                            >::type)
4256    : __ptr_(__r.get())
4257{
4258#if _LIBCPP_STD_VER > 11
4259    if (__ptr_ == nullptr)
4260        __cntrl_ = nullptr;
4261    else
4262#endif
4263    {
4264        typedef typename __shared_ptr_default_allocator<_Yp>::type _AllocT;
4265        typedef __shared_ptr_pointer<_Yp*, _Dp, _AllocT > _CntrlBlk;
4266        __cntrl_ = new _CntrlBlk(__r.get(), __r.get_deleter(), _AllocT());
4267        __enable_weak_this(__r.get(), __r.get());
4268    }
4269    __r.release();
4270}
4271
4272template<class _Tp>
4273template <class _Yp, class _Dp>
4274#ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES
4275shared_ptr<_Tp>::shared_ptr(unique_ptr<_Yp, _Dp>&& __r,
4276#else
4277shared_ptr<_Tp>::shared_ptr(unique_ptr<_Yp, _Dp> __r,
4278#endif
4279                            typename enable_if
4280                            <
4281                                is_lvalue_reference<_Dp>::value &&
4282                                !is_array<_Yp>::value &&
4283                                is_convertible<typename unique_ptr<_Yp, _Dp>::pointer, element_type*>::value,
4284                                __nat
4285                            >::type)
4286    : __ptr_(__r.get())
4287{
4288#if _LIBCPP_STD_VER > 11
4289    if (__ptr_ == nullptr)
4290        __cntrl_ = nullptr;
4291    else
4292#endif
4293    {
4294        typedef typename __shared_ptr_default_allocator<_Yp>::type _AllocT;
4295        typedef __shared_ptr_pointer<_Yp*,
4296                                     reference_wrapper<typename remove_reference<_Dp>::type>,
4297                                     _AllocT > _CntrlBlk;
4298        __cntrl_ = new _CntrlBlk(__r.get(), ref(__r.get_deleter()), _AllocT());
4299        __enable_weak_this(__r.get(), __r.get());
4300    }
4301    __r.release();
4302}
4303
4304#ifndef _LIBCPP_HAS_NO_VARIADICS
4305
4306template<class _Tp>
4307template<class ..._Args>
4308shared_ptr<_Tp>
4309shared_ptr<_Tp>::make_shared(_Args&& ...__args)
4310{
4311    static_assert( is_constructible<_Tp, _Args...>::value, "Can't construct object in make_shared" );
4312    typedef __shared_ptr_emplace<_Tp, allocator<_Tp> > _CntrlBlk;
4313    typedef allocator<_CntrlBlk> _A2;
4314    typedef __allocator_destructor<_A2> _D2;
4315    _A2 __a2;
4316    unique_ptr<_CntrlBlk, _D2> __hold2(__a2.allocate(1), _D2(__a2, 1));
4317    ::new(__hold2.get()) _CntrlBlk(__a2, _VSTD::forward<_Args>(__args)...);
4318    shared_ptr<_Tp> __r;
4319    __r.__ptr_ = __hold2.get()->get();
4320    __r.__cntrl_ = __hold2.release();
4321    __r.__enable_weak_this(__r.__ptr_, __r.__ptr_);
4322    return __r;
4323}
4324
4325template<class _Tp>
4326template<class _Alloc, class ..._Args>
4327shared_ptr<_Tp>
4328shared_ptr<_Tp>::allocate_shared(const _Alloc& __a, _Args&& ...__args)
4329{
4330    static_assert( is_constructible<_Tp, _Args...>::value, "Can't construct object in allocate_shared" );
4331    typedef __shared_ptr_emplace<_Tp, _Alloc> _CntrlBlk;
4332    typedef typename __allocator_traits_rebind<_Alloc, _CntrlBlk>::type _A2;
4333    typedef __allocator_destructor<_A2> _D2;
4334    _A2 __a2(__a);
4335    unique_ptr<_CntrlBlk, _D2> __hold2(__a2.allocate(1), _D2(__a2, 1));
4336    ::new(static_cast<void*>(_VSTD::addressof(*__hold2.get())))
4337        _CntrlBlk(__a, _VSTD::forward<_Args>(__args)...);
4338    shared_ptr<_Tp> __r;
4339    __r.__ptr_ = __hold2.get()->get();
4340    __r.__cntrl_ = _VSTD::addressof(*__hold2.release());
4341    __r.__enable_weak_this(__r.__ptr_, __r.__ptr_);
4342    return __r;
4343}
4344
4345#else  // _LIBCPP_HAS_NO_VARIADICS
4346
4347template<class _Tp>
4348shared_ptr<_Tp>
4349shared_ptr<_Tp>::make_shared()
4350{
4351    static_assert((is_constructible<_Tp>::value), "Can't construct object in make_shared" );
4352    typedef __shared_ptr_emplace<_Tp, allocator<_Tp> > _CntrlBlk;
4353    typedef allocator<_CntrlBlk> _Alloc2;
4354    typedef __allocator_destructor<_Alloc2> _D2;
4355    _Alloc2 __alloc2;
4356    unique_ptr<_CntrlBlk, _D2> __hold2(__alloc2.allocate(1), _D2(__alloc2, 1));
4357    ::new(__hold2.get()) _CntrlBlk(__alloc2);
4358    shared_ptr<_Tp> __r;
4359    __r.__ptr_ = __hold2.get()->get();
4360    __r.__cntrl_ = __hold2.release();
4361    __r.__enable_weak_this(__r.__ptr_, __r.__ptr_);
4362    return __r;
4363}
4364
4365template<class _Tp>
4366template<class _A0>
4367shared_ptr<_Tp>
4368shared_ptr<_Tp>::make_shared(_A0& __a0)
4369{
4370    static_assert((is_constructible<_Tp, _A0>::value), "Can't construct object in make_shared" );
4371    typedef __shared_ptr_emplace<_Tp, allocator<_Tp> > _CntrlBlk;
4372    typedef allocator<_CntrlBlk> _Alloc2;
4373    typedef __allocator_destructor<_Alloc2> _D2;
4374    _Alloc2 __alloc2;
4375    unique_ptr<_CntrlBlk, _D2> __hold2(__alloc2.allocate(1), _D2(__alloc2, 1));
4376    ::new(__hold2.get()) _CntrlBlk(__alloc2, __a0);
4377    shared_ptr<_Tp> __r;
4378    __r.__ptr_ = __hold2.get()->get();
4379    __r.__cntrl_ = __hold2.release();
4380    __r.__enable_weak_this(__r.__ptr_, __r.__ptr_);
4381    return __r;
4382}
4383
4384template<class _Tp>
4385template<class _A0, class _A1>
4386shared_ptr<_Tp>
4387shared_ptr<_Tp>::make_shared(_A0& __a0, _A1& __a1)
4388{
4389    static_assert((is_constructible<_Tp, _A0, _A1>::value), "Can't construct object in make_shared" );
4390    typedef __shared_ptr_emplace<_Tp, allocator<_Tp> > _CntrlBlk;
4391    typedef allocator<_CntrlBlk> _Alloc2;
4392    typedef __allocator_destructor<_Alloc2> _D2;
4393    _Alloc2 __alloc2;
4394    unique_ptr<_CntrlBlk, _D2> __hold2(__alloc2.allocate(1), _D2(__alloc2, 1));
4395    ::new(__hold2.get()) _CntrlBlk(__alloc2, __a0, __a1);
4396    shared_ptr<_Tp> __r;
4397    __r.__ptr_ = __hold2.get()->get();
4398    __r.__cntrl_ = __hold2.release();
4399    __r.__enable_weak_this(__r.__ptr_, __r.__ptr_);
4400    return __r;
4401}
4402
4403template<class _Tp>
4404template<class _A0, class _A1, class _A2>
4405shared_ptr<_Tp>
4406shared_ptr<_Tp>::make_shared(_A0& __a0, _A1& __a1, _A2& __a2)
4407{
4408    static_assert((is_constructible<_Tp, _A0, _A1, _A2>::value), "Can't construct object in make_shared" );
4409    typedef __shared_ptr_emplace<_Tp, allocator<_Tp> > _CntrlBlk;
4410    typedef allocator<_CntrlBlk> _Alloc2;
4411    typedef __allocator_destructor<_Alloc2> _D2;
4412    _Alloc2 __alloc2;
4413    unique_ptr<_CntrlBlk, _D2> __hold2(__alloc2.allocate(1), _D2(__alloc2, 1));
4414    ::new(__hold2.get()) _CntrlBlk(__alloc2, __a0, __a1, __a2);
4415    shared_ptr<_Tp> __r;
4416    __r.__ptr_ = __hold2.get()->get();
4417    __r.__cntrl_ = __hold2.release();
4418    __r.__enable_weak_this(__r.__ptr_, __r.__ptr_);
4419    return __r;
4420}
4421
4422template<class _Tp>
4423template<class _Alloc>
4424shared_ptr<_Tp>
4425shared_ptr<_Tp>::allocate_shared(const _Alloc& __a)
4426{
4427    static_assert((is_constructible<_Tp>::value), "Can't construct object in allocate_shared" );
4428    typedef __shared_ptr_emplace<_Tp, _Alloc> _CntrlBlk;
4429    typedef typename __allocator_traits_rebind<_Alloc, _CntrlBlk>::type _Alloc2;
4430    typedef __allocator_destructor<_Alloc2> _D2;
4431    _Alloc2 __alloc2(__a);
4432    unique_ptr<_CntrlBlk, _D2> __hold2(__alloc2.allocate(1), _D2(__alloc2, 1));
4433    ::new(static_cast<void*>(_VSTD::addressof(*__hold2.get())))
4434        _CntrlBlk(__a);
4435    shared_ptr<_Tp> __r;
4436    __r.__ptr_ = __hold2.get()->get();
4437    __r.__cntrl_ = _VSTD::addressof(*__hold2.release());
4438    __r.__enable_weak_this(__r.__ptr_, __r.__ptr_);
4439    return __r;
4440}
4441
4442template<class _Tp>
4443template<class _Alloc, class _A0>
4444shared_ptr<_Tp>
4445shared_ptr<_Tp>::allocate_shared(const _Alloc& __a, _A0& __a0)
4446{
4447    static_assert((is_constructible<_Tp, _A0>::value), "Can't construct object in allocate_shared" );
4448    typedef __shared_ptr_emplace<_Tp, _Alloc> _CntrlBlk;
4449    typedef typename __allocator_traits_rebind<_Alloc, _CntrlBlk>::type _Alloc2;
4450    typedef __allocator_destructor<_Alloc2> _D2;
4451    _Alloc2 __alloc2(__a);
4452    unique_ptr<_CntrlBlk, _D2> __hold2(__alloc2.allocate(1), _D2(__alloc2, 1));
4453    ::new(static_cast<void*>(_VSTD::addressof(*__hold2.get())))
4454        _CntrlBlk(__a, __a0);
4455    shared_ptr<_Tp> __r;
4456    __r.__ptr_ = __hold2.get()->get();
4457    __r.__cntrl_ = _VSTD::addressof(*__hold2.release());
4458    __r.__enable_weak_this(__r.__ptr_, __r.__ptr_);
4459    return __r;
4460}
4461
4462template<class _Tp>
4463template<class _Alloc, class _A0, class _A1>
4464shared_ptr<_Tp>
4465shared_ptr<_Tp>::allocate_shared(const _Alloc& __a, _A0& __a0, _A1& __a1)
4466{
4467    static_assert((is_constructible<_Tp, _A0, _A1>::value), "Can't construct object in allocate_shared" );
4468    typedef __shared_ptr_emplace<_Tp, _Alloc> _CntrlBlk;
4469    typedef typename __allocator_traits_rebind<_Alloc, _CntrlBlk>::type _Alloc2;
4470    typedef __allocator_destructor<_Alloc2> _D2;
4471    _Alloc2 __alloc2(__a);
4472    unique_ptr<_CntrlBlk, _D2> __hold2(__alloc2.allocate(1), _D2(__alloc2, 1));
4473    ::new(static_cast<void*>(_VSTD::addressof(*__hold2.get())))
4474        _CntrlBlk(__a, __a0, __a1);
4475    shared_ptr<_Tp> __r;
4476    __r.__ptr_ = __hold2.get()->get();
4477    __r.__cntrl_ = _VSTD::addressof(*__hold2.release());
4478    __r.__enable_weak_this(__r.__ptr_, __r.__ptr_);
4479    return __r;
4480}
4481
4482template<class _Tp>
4483template<class _Alloc, class _A0, class _A1, class _A2>
4484shared_ptr<_Tp>
4485shared_ptr<_Tp>::allocate_shared(const _Alloc& __a, _A0& __a0, _A1& __a1, _A2& __a2)
4486{
4487    static_assert((is_constructible<_Tp, _A0, _A1, _A2>::value), "Can't construct object in allocate_shared" );
4488    typedef __shared_ptr_emplace<_Tp, _Alloc> _CntrlBlk;
4489    typedef typename __allocator_traits_rebind<_Alloc, _CntrlBlk>::type _Alloc2;
4490    typedef __allocator_destructor<_Alloc2> _D2;
4491    _Alloc2 __alloc2(__a);
4492    unique_ptr<_CntrlBlk, _D2> __hold2(__alloc2.allocate(1), _D2(__alloc2, 1));
4493    ::new(static_cast<void*>(_VSTD::addressof(*__hold2.get())))
4494        _CntrlBlk(__a, __a0, __a1, __a2);
4495    shared_ptr<_Tp> __r;
4496    __r.__ptr_ = __hold2.get()->get();
4497    __r.__cntrl_ = _VSTD::addressof(*__hold2.release());
4498    __r.__enable_weak_this(__r.__ptr_, __r.__ptr_);
4499    return __r;
4500}
4501
4502#endif  // _LIBCPP_HAS_NO_VARIADICS
4503
4504template<class _Tp>
4505shared_ptr<_Tp>::~shared_ptr()
4506{
4507    if (__cntrl_)
4508        __cntrl_->__release_shared();
4509}
4510
4511template<class _Tp>
4512inline
4513shared_ptr<_Tp>&
4514shared_ptr<_Tp>::operator=(const shared_ptr& __r) _NOEXCEPT
4515{
4516    shared_ptr(__r).swap(*this);
4517    return *this;
4518}
4519
4520template<class _Tp>
4521template<class _Yp>
4522inline
4523typename enable_if
4524<
4525    is_convertible<_Yp*, typename shared_ptr<_Tp>::element_type*>::value,
4526    shared_ptr<_Tp>&
4527>::type
4528shared_ptr<_Tp>::operator=(const shared_ptr<_Yp>& __r) _NOEXCEPT
4529{
4530    shared_ptr(__r).swap(*this);
4531    return *this;
4532}
4533
4534#ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES
4535
4536template<class _Tp>
4537inline
4538shared_ptr<_Tp>&
4539shared_ptr<_Tp>::operator=(shared_ptr&& __r) _NOEXCEPT
4540{
4541    shared_ptr(_VSTD::move(__r)).swap(*this);
4542    return *this;
4543}
4544
4545template<class _Tp>
4546template<class _Yp>
4547inline
4548typename enable_if
4549<
4550    is_convertible<_Yp*, typename shared_ptr<_Tp>::element_type*>::value,
4551    shared_ptr<_Tp>&
4552>::type
4553shared_ptr<_Tp>::operator=(shared_ptr<_Yp>&& __r)
4554{
4555    shared_ptr(_VSTD::move(__r)).swap(*this);
4556    return *this;
4557}
4558
4559#if _LIBCPP_STD_VER <= 14 || defined(_LIBCPP_ENABLE_CXX17_REMOVED_AUTO_PTR)
4560template<class _Tp>
4561template<class _Yp>
4562inline
4563typename enable_if
4564<
4565    !is_array<_Yp>::value &&
4566    is_convertible<_Yp*, typename shared_ptr<_Tp>::element_type*>::value,
4567    shared_ptr<_Tp>
4568>::type&
4569shared_ptr<_Tp>::operator=(auto_ptr<_Yp>&& __r)
4570{
4571    shared_ptr(_VSTD::move(__r)).swap(*this);
4572    return *this;
4573}
4574#endif
4575
4576template<class _Tp>
4577template <class _Yp, class _Dp>
4578inline
4579typename enable_if
4580<
4581    !is_array<_Yp>::value &&
4582    is_convertible<typename unique_ptr<_Yp, _Dp>::pointer,
4583                   typename shared_ptr<_Tp>::element_type*>::value,
4584    shared_ptr<_Tp>&
4585>::type
4586shared_ptr<_Tp>::operator=(unique_ptr<_Yp, _Dp>&& __r)
4587{
4588    shared_ptr(_VSTD::move(__r)).swap(*this);
4589    return *this;
4590}
4591
4592#else  // _LIBCPP_HAS_NO_RVALUE_REFERENCES
4593
4594#if _LIBCPP_STD_VER <= 14 || defined(_LIBCPP_ENABLE_CXX17_REMOVED_AUTO_PTR)
4595template<class _Tp>
4596template<class _Yp>
4597inline _LIBCPP_INLINE_VISIBILITY
4598typename enable_if
4599<
4600    !is_array<_Yp>::value &&
4601    is_convertible<_Yp*, typename shared_ptr<_Tp>::element_type*>::value,
4602    shared_ptr<_Tp>&
4603>::type
4604shared_ptr<_Tp>::operator=(auto_ptr<_Yp> __r)
4605{
4606    shared_ptr(__r).swap(*this);
4607    return *this;
4608}
4609#endif
4610
4611template<class _Tp>
4612template <class _Yp, class _Dp>
4613inline _LIBCPP_INLINE_VISIBILITY
4614typename enable_if
4615<
4616    !is_array<_Yp>::value &&
4617    is_convertible<typename unique_ptr<_Yp, _Dp>::pointer,
4618                   typename shared_ptr<_Tp>::element_type*>::value,
4619    shared_ptr<_Tp>&
4620>::type
4621shared_ptr<_Tp>::operator=(unique_ptr<_Yp, _Dp> __r)
4622{
4623    shared_ptr(_VSTD::move(__r)).swap(*this);
4624    return *this;
4625}
4626
4627#endif  // _LIBCPP_HAS_NO_RVALUE_REFERENCES
4628
4629template<class _Tp>
4630inline
4631void
4632shared_ptr<_Tp>::swap(shared_ptr& __r) _NOEXCEPT
4633{
4634    _VSTD::swap(__ptr_, __r.__ptr_);
4635    _VSTD::swap(__cntrl_, __r.__cntrl_);
4636}
4637
4638template<class _Tp>
4639inline
4640void
4641shared_ptr<_Tp>::reset() _NOEXCEPT
4642{
4643    shared_ptr().swap(*this);
4644}
4645
4646template<class _Tp>
4647template<class _Yp>
4648inline
4649typename enable_if
4650<
4651    is_convertible<_Yp*, typename shared_ptr<_Tp>::element_type*>::value,
4652    void
4653>::type
4654shared_ptr<_Tp>::reset(_Yp* __p)
4655{
4656    shared_ptr(__p).swap(*this);
4657}
4658
4659template<class _Tp>
4660template<class _Yp, class _Dp>
4661inline
4662typename enable_if
4663<
4664    is_convertible<_Yp*, typename shared_ptr<_Tp>::element_type*>::value,
4665    void
4666>::type
4667shared_ptr<_Tp>::reset(_Yp* __p, _Dp __d)
4668{
4669    shared_ptr(__p, __d).swap(*this);
4670}
4671
4672template<class _Tp>
4673template<class _Yp, class _Dp, class _Alloc>
4674inline
4675typename enable_if
4676<
4677    is_convertible<_Yp*, typename shared_ptr<_Tp>::element_type*>::value,
4678    void
4679>::type
4680shared_ptr<_Tp>::reset(_Yp* __p, _Dp __d, _Alloc __a)
4681{
4682    shared_ptr(__p, __d, __a).swap(*this);
4683}
4684
4685#ifndef _LIBCPP_HAS_NO_VARIADICS
4686
4687template<class _Tp, class ..._Args>
4688inline _LIBCPP_INLINE_VISIBILITY
4689typename enable_if
4690<
4691    !is_array<_Tp>::value,
4692    shared_ptr<_Tp>
4693>::type
4694make_shared(_Args&& ...__args)
4695{
4696    return shared_ptr<_Tp>::make_shared(_VSTD::forward<_Args>(__args)...);
4697}
4698
4699template<class _Tp, class _Alloc, class ..._Args>
4700inline _LIBCPP_INLINE_VISIBILITY
4701typename enable_if
4702<
4703    !is_array<_Tp>::value,
4704    shared_ptr<_Tp>
4705>::type
4706allocate_shared(const _Alloc& __a, _Args&& ...__args)
4707{
4708    return shared_ptr<_Tp>::allocate_shared(__a, _VSTD::forward<_Args>(__args)...);
4709}
4710
4711#else  // _LIBCPP_HAS_NO_VARIADICS
4712
4713template<class _Tp>
4714inline _LIBCPP_INLINE_VISIBILITY
4715shared_ptr<_Tp>
4716make_shared()
4717{
4718    return shared_ptr<_Tp>::make_shared();
4719}
4720
4721template<class _Tp, class _A0>
4722inline _LIBCPP_INLINE_VISIBILITY
4723shared_ptr<_Tp>
4724make_shared(_A0& __a0)
4725{
4726    return shared_ptr<_Tp>::make_shared(__a0);
4727}
4728
4729template<class _Tp, class _A0, class _A1>
4730inline _LIBCPP_INLINE_VISIBILITY
4731shared_ptr<_Tp>
4732make_shared(_A0& __a0, _A1& __a1)
4733{
4734    return shared_ptr<_Tp>::make_shared(__a0, __a1);
4735}
4736
4737template<class _Tp, class _A0, class _A1, class _A2>
4738inline _LIBCPP_INLINE_VISIBILITY
4739shared_ptr<_Tp>
4740make_shared(_A0& __a0, _A1& __a1, _A2& __a2)
4741{
4742    return shared_ptr<_Tp>::make_shared(__a0, __a1, __a2);
4743}
4744
4745template<class _Tp, class _Alloc>
4746inline _LIBCPP_INLINE_VISIBILITY
4747shared_ptr<_Tp>
4748allocate_shared(const _Alloc& __a)
4749{
4750    return shared_ptr<_Tp>::allocate_shared(__a);
4751}
4752
4753template<class _Tp, class _Alloc, class _A0>
4754inline _LIBCPP_INLINE_VISIBILITY
4755shared_ptr<_Tp>
4756allocate_shared(const _Alloc& __a, _A0& __a0)
4757{
4758    return shared_ptr<_Tp>::allocate_shared(__a, __a0);
4759}
4760
4761template<class _Tp, class _Alloc, class _A0, class _A1>
4762inline _LIBCPP_INLINE_VISIBILITY
4763shared_ptr<_Tp>
4764allocate_shared(const _Alloc& __a, _A0& __a0, _A1& __a1)
4765{
4766    return shared_ptr<_Tp>::allocate_shared(__a, __a0, __a1);
4767}
4768
4769template<class _Tp, class _Alloc, class _A0, class _A1, class _A2>
4770inline _LIBCPP_INLINE_VISIBILITY
4771shared_ptr<_Tp>
4772allocate_shared(const _Alloc& __a, _A0& __a0, _A1& __a1, _A2& __a2)
4773{
4774    return shared_ptr<_Tp>::allocate_shared(__a, __a0, __a1, __a2);
4775}
4776
4777#endif  // _LIBCPP_HAS_NO_VARIADICS
4778
4779template<class _Tp, class _Up>
4780inline _LIBCPP_INLINE_VISIBILITY
4781bool
4782operator==(const shared_ptr<_Tp>& __x, const shared_ptr<_Up>& __y) _NOEXCEPT
4783{
4784    return __x.get() == __y.get();
4785}
4786
4787template<class _Tp, class _Up>
4788inline _LIBCPP_INLINE_VISIBILITY
4789bool
4790operator!=(const shared_ptr<_Tp>& __x, const shared_ptr<_Up>& __y) _NOEXCEPT
4791{
4792    return !(__x == __y);
4793}
4794
4795template<class _Tp, class _Up>
4796inline _LIBCPP_INLINE_VISIBILITY
4797bool
4798operator<(const shared_ptr<_Tp>& __x, const shared_ptr<_Up>& __y) _NOEXCEPT
4799{
4800#if _LIBCPP_STD_VER <= 11
4801    typedef typename common_type<_Tp*, _Up*>::type _Vp;
4802    return less<_Vp>()(__x.get(), __y.get());
4803#else
4804    return less<>()(__x.get(), __y.get());
4805#endif
4806
4807}
4808
4809template<class _Tp, class _Up>
4810inline _LIBCPP_INLINE_VISIBILITY
4811bool
4812operator>(const shared_ptr<_Tp>& __x, const shared_ptr<_Up>& __y) _NOEXCEPT
4813{
4814    return __y < __x;
4815}
4816
4817template<class _Tp, class _Up>
4818inline _LIBCPP_INLINE_VISIBILITY
4819bool
4820operator<=(const shared_ptr<_Tp>& __x, const shared_ptr<_Up>& __y) _NOEXCEPT
4821{
4822    return !(__y < __x);
4823}
4824
4825template<class _Tp, class _Up>
4826inline _LIBCPP_INLINE_VISIBILITY
4827bool
4828operator>=(const shared_ptr<_Tp>& __x, const shared_ptr<_Up>& __y) _NOEXCEPT
4829{
4830    return !(__x < __y);
4831}
4832
4833template<class _Tp>
4834inline _LIBCPP_INLINE_VISIBILITY
4835bool
4836operator==(const shared_ptr<_Tp>& __x, nullptr_t) _NOEXCEPT
4837{
4838    return !__x;
4839}
4840
4841template<class _Tp>
4842inline _LIBCPP_INLINE_VISIBILITY
4843bool
4844operator==(nullptr_t, const shared_ptr<_Tp>& __x) _NOEXCEPT
4845{
4846    return !__x;
4847}
4848
4849template<class _Tp>
4850inline _LIBCPP_INLINE_VISIBILITY
4851bool
4852operator!=(const shared_ptr<_Tp>& __x, nullptr_t) _NOEXCEPT
4853{
4854    return static_cast<bool>(__x);
4855}
4856
4857template<class _Tp>
4858inline _LIBCPP_INLINE_VISIBILITY
4859bool
4860operator!=(nullptr_t, const shared_ptr<_Tp>& __x) _NOEXCEPT
4861{
4862    return static_cast<bool>(__x);
4863}
4864
4865template<class _Tp>
4866inline _LIBCPP_INLINE_VISIBILITY
4867bool
4868operator<(const shared_ptr<_Tp>& __x, nullptr_t) _NOEXCEPT
4869{
4870    return less<_Tp*>()(__x.get(), nullptr);
4871}
4872
4873template<class _Tp>
4874inline _LIBCPP_INLINE_VISIBILITY
4875bool
4876operator<(nullptr_t, const shared_ptr<_Tp>& __x) _NOEXCEPT
4877{
4878    return less<_Tp*>()(nullptr, __x.get());
4879}
4880
4881template<class _Tp>
4882inline _LIBCPP_INLINE_VISIBILITY
4883bool
4884operator>(const shared_ptr<_Tp>& __x, nullptr_t) _NOEXCEPT
4885{
4886    return nullptr < __x;
4887}
4888
4889template<class _Tp>
4890inline _LIBCPP_INLINE_VISIBILITY
4891bool
4892operator>(nullptr_t, const shared_ptr<_Tp>& __x) _NOEXCEPT
4893{
4894    return __x < nullptr;
4895}
4896
4897template<class _Tp>
4898inline _LIBCPP_INLINE_VISIBILITY
4899bool
4900operator<=(const shared_ptr<_Tp>& __x, nullptr_t) _NOEXCEPT
4901{
4902    return !(nullptr < __x);
4903}
4904
4905template<class _Tp>
4906inline _LIBCPP_INLINE_VISIBILITY
4907bool
4908operator<=(nullptr_t, const shared_ptr<_Tp>& __x) _NOEXCEPT
4909{
4910    return !(__x < nullptr);
4911}
4912
4913template<class _Tp>
4914inline _LIBCPP_INLINE_VISIBILITY
4915bool
4916operator>=(const shared_ptr<_Tp>& __x, nullptr_t) _NOEXCEPT
4917{
4918    return !(__x < nullptr);
4919}
4920
4921template<class _Tp>
4922inline _LIBCPP_INLINE_VISIBILITY
4923bool
4924operator>=(nullptr_t, const shared_ptr<_Tp>& __x) _NOEXCEPT
4925{
4926    return !(nullptr < __x);
4927}
4928
4929template<class _Tp>
4930inline _LIBCPP_INLINE_VISIBILITY
4931void
4932swap(shared_ptr<_Tp>& __x, shared_ptr<_Tp>& __y) _NOEXCEPT
4933{
4934    __x.swap(__y);
4935}
4936
4937template<class _Tp, class _Up>
4938inline _LIBCPP_INLINE_VISIBILITY
4939typename enable_if
4940<
4941    !is_array<_Tp>::value && !is_array<_Up>::value,
4942    shared_ptr<_Tp>
4943>::type
4944static_pointer_cast(const shared_ptr<_Up>& __r) _NOEXCEPT
4945{
4946    return shared_ptr<_Tp>(__r, static_cast<_Tp*>(__r.get()));
4947}
4948
4949template<class _Tp, class _Up>
4950inline _LIBCPP_INLINE_VISIBILITY
4951typename enable_if
4952<
4953    !is_array<_Tp>::value && !is_array<_Up>::value,
4954    shared_ptr<_Tp>
4955>::type
4956dynamic_pointer_cast(const shared_ptr<_Up>& __r) _NOEXCEPT
4957{
4958    _Tp* __p = dynamic_cast<_Tp*>(__r.get());
4959    return __p ? shared_ptr<_Tp>(__r, __p) : shared_ptr<_Tp>();
4960}
4961
4962template<class _Tp, class _Up>
4963typename enable_if
4964<
4965    is_array<_Tp>::value == is_array<_Up>::value,
4966    shared_ptr<_Tp>
4967>::type
4968const_pointer_cast(const shared_ptr<_Up>& __r) _NOEXCEPT
4969{
4970    typedef typename remove_extent<_Tp>::type _RTp;
4971    return shared_ptr<_Tp>(__r, const_cast<_RTp*>(__r.get()));
4972}
4973
4974#ifndef _LIBCPP_NO_RTTI
4975
4976template<class _Dp, class _Tp>
4977inline _LIBCPP_INLINE_VISIBILITY
4978_Dp*
4979get_deleter(const shared_ptr<_Tp>& __p) _NOEXCEPT
4980{
4981    return __p.template __get_deleter<_Dp>();
4982}
4983
4984#endif  // _LIBCPP_NO_RTTI
4985
4986template<class _Tp>
4987class _LIBCPP_TEMPLATE_VIS weak_ptr
4988{
4989public:
4990    typedef _Tp element_type;
4991private:
4992    element_type*        __ptr_;
4993    __shared_weak_count* __cntrl_;
4994
4995public:
4996    _LIBCPP_INLINE_VISIBILITY
4997    _LIBCPP_CONSTEXPR weak_ptr() _NOEXCEPT;
4998    template<class _Yp> _LIBCPP_INLINE_VISIBILITY weak_ptr(shared_ptr<_Yp> const& __r,
4999                   typename enable_if<is_convertible<_Yp*, _Tp*>::value, __nat*>::type = 0)
5000                        _NOEXCEPT;
5001    _LIBCPP_INLINE_VISIBILITY
5002    weak_ptr(weak_ptr const& __r) _NOEXCEPT;
5003    template<class _Yp> _LIBCPP_INLINE_VISIBILITY weak_ptr(weak_ptr<_Yp> const& __r,
5004                   typename enable_if<is_convertible<_Yp*, _Tp*>::value, __nat*>::type = 0)
5005                         _NOEXCEPT;
5006
5007#ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES
5008    _LIBCPP_INLINE_VISIBILITY
5009    weak_ptr(weak_ptr&& __r) _NOEXCEPT;
5010    template<class _Yp> _LIBCPP_INLINE_VISIBILITY weak_ptr(weak_ptr<_Yp>&& __r,
5011                   typename enable_if<is_convertible<_Yp*, _Tp*>::value, __nat*>::type = 0)
5012                         _NOEXCEPT;
5013#endif  // _LIBCPP_HAS_NO_RVALUE_REFERENCES
5014    ~weak_ptr();
5015
5016    _LIBCPP_INLINE_VISIBILITY
5017    weak_ptr& operator=(weak_ptr const& __r) _NOEXCEPT;
5018    template<class _Yp>
5019        typename enable_if
5020        <
5021            is_convertible<_Yp*, element_type*>::value,
5022            weak_ptr&
5023        >::type
5024        _LIBCPP_INLINE_VISIBILITY
5025        operator=(weak_ptr<_Yp> const& __r) _NOEXCEPT;
5026
5027#ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES
5028
5029    _LIBCPP_INLINE_VISIBILITY
5030    weak_ptr& operator=(weak_ptr&& __r) _NOEXCEPT;
5031    template<class _Yp>
5032        typename enable_if
5033        <
5034            is_convertible<_Yp*, element_type*>::value,
5035            weak_ptr&
5036        >::type
5037        _LIBCPP_INLINE_VISIBILITY
5038        operator=(weak_ptr<_Yp>&& __r) _NOEXCEPT;
5039
5040#endif  // _LIBCPP_HAS_NO_RVALUE_REFERENCES
5041
5042    template<class _Yp>
5043        typename enable_if
5044        <
5045            is_convertible<_Yp*, element_type*>::value,
5046            weak_ptr&
5047        >::type
5048        _LIBCPP_INLINE_VISIBILITY
5049        operator=(shared_ptr<_Yp> const& __r) _NOEXCEPT;
5050
5051    _LIBCPP_INLINE_VISIBILITY
5052    void swap(weak_ptr& __r) _NOEXCEPT;
5053    _LIBCPP_INLINE_VISIBILITY
5054    void reset() _NOEXCEPT;
5055
5056    _LIBCPP_INLINE_VISIBILITY
5057    long use_count() const _NOEXCEPT
5058        {return __cntrl_ ? __cntrl_->use_count() : 0;}
5059    _LIBCPP_INLINE_VISIBILITY
5060    bool expired() const _NOEXCEPT
5061        {return __cntrl_ == 0 || __cntrl_->use_count() == 0;}
5062    shared_ptr<_Tp> lock() const _NOEXCEPT;
5063    template<class _Up>
5064        _LIBCPP_INLINE_VISIBILITY
5065        bool owner_before(const shared_ptr<_Up>& __r) const _NOEXCEPT
5066        {return __cntrl_ < __r.__cntrl_;}
5067    template<class _Up>
5068        _LIBCPP_INLINE_VISIBILITY
5069        bool owner_before(const weak_ptr<_Up>& __r) const _NOEXCEPT
5070        {return __cntrl_ < __r.__cntrl_;}
5071
5072    template <class _Up> friend class _LIBCPP_TEMPLATE_VIS weak_ptr;
5073    template <class _Up> friend class _LIBCPP_TEMPLATE_VIS shared_ptr;
5074};
5075
5076template<class _Tp>
5077inline
5078_LIBCPP_CONSTEXPR
5079weak_ptr<_Tp>::weak_ptr() _NOEXCEPT
5080    : __ptr_(0),
5081      __cntrl_(0)
5082{
5083}
5084
5085template<class _Tp>
5086inline
5087weak_ptr<_Tp>::weak_ptr(weak_ptr const& __r) _NOEXCEPT
5088    : __ptr_(__r.__ptr_),
5089      __cntrl_(__r.__cntrl_)
5090{
5091    if (__cntrl_)
5092        __cntrl_->__add_weak();
5093}
5094
5095template<class _Tp>
5096template<class _Yp>
5097inline
5098weak_ptr<_Tp>::weak_ptr(shared_ptr<_Yp> const& __r,
5099                        typename enable_if<is_convertible<_Yp*, _Tp*>::value, __nat*>::type)
5100                         _NOEXCEPT
5101    : __ptr_(__r.__ptr_),
5102      __cntrl_(__r.__cntrl_)
5103{
5104    if (__cntrl_)
5105        __cntrl_->__add_weak();
5106}
5107
5108template<class _Tp>
5109template<class _Yp>
5110inline
5111weak_ptr<_Tp>::weak_ptr(weak_ptr<_Yp> const& __r,
5112                        typename enable_if<is_convertible<_Yp*, _Tp*>::value, __nat*>::type)
5113         _NOEXCEPT
5114    : __ptr_(__r.__ptr_),
5115      __cntrl_(__r.__cntrl_)
5116{
5117    if (__cntrl_)
5118        __cntrl_->__add_weak();
5119}
5120
5121#ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES
5122
5123template<class _Tp>
5124inline
5125weak_ptr<_Tp>::weak_ptr(weak_ptr&& __r) _NOEXCEPT
5126    : __ptr_(__r.__ptr_),
5127      __cntrl_(__r.__cntrl_)
5128{
5129    __r.__ptr_ = 0;
5130    __r.__cntrl_ = 0;
5131}
5132
5133template<class _Tp>
5134template<class _Yp>
5135inline
5136weak_ptr<_Tp>::weak_ptr(weak_ptr<_Yp>&& __r,
5137                        typename enable_if<is_convertible<_Yp*, _Tp*>::value, __nat*>::type)
5138         _NOEXCEPT
5139    : __ptr_(__r.__ptr_),
5140      __cntrl_(__r.__cntrl_)
5141{
5142    __r.__ptr_ = 0;
5143    __r.__cntrl_ = 0;
5144}
5145
5146#endif  // _LIBCPP_HAS_NO_RVALUE_REFERENCES
5147
5148template<class _Tp>
5149weak_ptr<_Tp>::~weak_ptr()
5150{
5151    if (__cntrl_)
5152        __cntrl_->__release_weak();
5153}
5154
5155template<class _Tp>
5156inline
5157weak_ptr<_Tp>&
5158weak_ptr<_Tp>::operator=(weak_ptr const& __r) _NOEXCEPT
5159{
5160    weak_ptr(__r).swap(*this);
5161    return *this;
5162}
5163
5164template<class _Tp>
5165template<class _Yp>
5166inline
5167typename enable_if
5168<
5169    is_convertible<_Yp*, _Tp*>::value,
5170    weak_ptr<_Tp>&
5171>::type
5172weak_ptr<_Tp>::operator=(weak_ptr<_Yp> const& __r) _NOEXCEPT
5173{
5174    weak_ptr(__r).swap(*this);
5175    return *this;
5176}
5177
5178#ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES
5179
5180template<class _Tp>
5181inline
5182weak_ptr<_Tp>&
5183weak_ptr<_Tp>::operator=(weak_ptr&& __r) _NOEXCEPT
5184{
5185    weak_ptr(_VSTD::move(__r)).swap(*this);
5186    return *this;
5187}
5188
5189template<class _Tp>
5190template<class _Yp>
5191inline
5192typename enable_if
5193<
5194    is_convertible<_Yp*, _Tp*>::value,
5195    weak_ptr<_Tp>&
5196>::type
5197weak_ptr<_Tp>::operator=(weak_ptr<_Yp>&& __r) _NOEXCEPT
5198{
5199    weak_ptr(_VSTD::move(__r)).swap(*this);
5200    return *this;
5201}
5202
5203#endif  // _LIBCPP_HAS_NO_RVALUE_REFERENCES
5204
5205template<class _Tp>
5206template<class _Yp>
5207inline
5208typename enable_if
5209<
5210    is_convertible<_Yp*, _Tp*>::value,
5211    weak_ptr<_Tp>&
5212>::type
5213weak_ptr<_Tp>::operator=(shared_ptr<_Yp> const& __r) _NOEXCEPT
5214{
5215    weak_ptr(__r).swap(*this);
5216    return *this;
5217}
5218
5219template<class _Tp>
5220inline
5221void
5222weak_ptr<_Tp>::swap(weak_ptr& __r) _NOEXCEPT
5223{
5224    _VSTD::swap(__ptr_, __r.__ptr_);
5225    _VSTD::swap(__cntrl_, __r.__cntrl_);
5226}
5227
5228template<class _Tp>
5229inline _LIBCPP_INLINE_VISIBILITY
5230void
5231swap(weak_ptr<_Tp>& __x, weak_ptr<_Tp>& __y) _NOEXCEPT
5232{
5233    __x.swap(__y);
5234}
5235
5236template<class _Tp>
5237inline
5238void
5239weak_ptr<_Tp>::reset() _NOEXCEPT
5240{
5241    weak_ptr().swap(*this);
5242}
5243
5244template<class _Tp>
5245template<class _Yp>
5246shared_ptr<_Tp>::shared_ptr(const weak_ptr<_Yp>& __r,
5247                            typename enable_if<is_convertible<_Yp*, element_type*>::value, __nat>::type)
5248    : __ptr_(__r.__ptr_),
5249      __cntrl_(__r.__cntrl_ ? __r.__cntrl_->lock() : __r.__cntrl_)
5250{
5251    if (__cntrl_ == 0)
5252        __throw_bad_weak_ptr();
5253}
5254
5255template<class _Tp>
5256shared_ptr<_Tp>
5257weak_ptr<_Tp>::lock() const _NOEXCEPT
5258{
5259    shared_ptr<_Tp> __r;
5260    __r.__cntrl_ = __cntrl_ ? __cntrl_->lock() : __cntrl_;
5261    if (__r.__cntrl_)
5262        __r.__ptr_ = __ptr_;
5263    return __r;
5264}
5265
5266#if _LIBCPP_STD_VER > 14
5267template <class _Tp = void> struct owner_less;
5268#else
5269template <class _Tp> struct owner_less;
5270#endif
5271
5272template <class _Tp>
5273struct _LIBCPP_TEMPLATE_VIS owner_less<shared_ptr<_Tp> >
5274    : binary_function<shared_ptr<_Tp>, shared_ptr<_Tp>, bool>
5275{
5276    typedef bool result_type;
5277    _LIBCPP_INLINE_VISIBILITY
5278    bool operator()(shared_ptr<_Tp> const& __x, shared_ptr<_Tp> const& __y) const _NOEXCEPT
5279        {return __x.owner_before(__y);}
5280    _LIBCPP_INLINE_VISIBILITY
5281    bool operator()(shared_ptr<_Tp> const& __x,   weak_ptr<_Tp> const& __y) const _NOEXCEPT
5282        {return __x.owner_before(__y);}
5283    _LIBCPP_INLINE_VISIBILITY
5284    bool operator()(  weak_ptr<_Tp> const& __x, shared_ptr<_Tp> const& __y) const _NOEXCEPT
5285        {return __x.owner_before(__y);}
5286};
5287
5288template <class _Tp>
5289struct _LIBCPP_TEMPLATE_VIS owner_less<weak_ptr<_Tp> >
5290    : binary_function<weak_ptr<_Tp>, weak_ptr<_Tp>, bool>
5291{
5292    typedef bool result_type;
5293    _LIBCPP_INLINE_VISIBILITY
5294    bool operator()(  weak_ptr<_Tp> const& __x,   weak_ptr<_Tp> const& __y) const _NOEXCEPT
5295        {return __x.owner_before(__y);}
5296    _LIBCPP_INLINE_VISIBILITY
5297    bool operator()(shared_ptr<_Tp> const& __x,   weak_ptr<_Tp> const& __y) const _NOEXCEPT
5298        {return __x.owner_before(__y);}
5299    _LIBCPP_INLINE_VISIBILITY
5300    bool operator()(  weak_ptr<_Tp> const& __x, shared_ptr<_Tp> const& __y) const _NOEXCEPT
5301        {return __x.owner_before(__y);}
5302};
5303
5304#if _LIBCPP_STD_VER > 14
5305template <>
5306struct _LIBCPP_TEMPLATE_VIS owner_less<void>
5307{
5308    template <class _Tp, class _Up>
5309    _LIBCPP_INLINE_VISIBILITY
5310    bool operator()( shared_ptr<_Tp> const& __x, shared_ptr<_Up> const& __y) const _NOEXCEPT
5311        {return __x.owner_before(__y);}
5312    template <class _Tp, class _Up>
5313    _LIBCPP_INLINE_VISIBILITY
5314    bool operator()( shared_ptr<_Tp> const& __x,   weak_ptr<_Up> const& __y) const _NOEXCEPT
5315        {return __x.owner_before(__y);}
5316    template <class _Tp, class _Up>
5317    _LIBCPP_INLINE_VISIBILITY
5318    bool operator()(   weak_ptr<_Tp> const& __x, shared_ptr<_Up> const& __y) const _NOEXCEPT
5319        {return __x.owner_before(__y);}
5320    template <class _Tp, class _Up>
5321    _LIBCPP_INLINE_VISIBILITY
5322    bool operator()(   weak_ptr<_Tp> const& __x,   weak_ptr<_Up> const& __y) const _NOEXCEPT
5323        {return __x.owner_before(__y);}
5324    typedef void is_transparent;
5325};
5326#endif
5327
5328template<class _Tp>
5329class _LIBCPP_TEMPLATE_VIS enable_shared_from_this
5330{
5331    mutable weak_ptr<_Tp> __weak_this_;
5332protected:
5333    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR
5334    enable_shared_from_this() _NOEXCEPT {}
5335    _LIBCPP_INLINE_VISIBILITY
5336    enable_shared_from_this(enable_shared_from_this const&) _NOEXCEPT {}
5337    _LIBCPP_INLINE_VISIBILITY
5338    enable_shared_from_this& operator=(enable_shared_from_this const&) _NOEXCEPT
5339        {return *this;}
5340    _LIBCPP_INLINE_VISIBILITY
5341    ~enable_shared_from_this() {}
5342public:
5343    _LIBCPP_INLINE_VISIBILITY
5344    shared_ptr<_Tp> shared_from_this()
5345        {return shared_ptr<_Tp>(__weak_this_);}
5346    _LIBCPP_INLINE_VISIBILITY
5347    shared_ptr<_Tp const> shared_from_this() const
5348        {return shared_ptr<const _Tp>(__weak_this_);}
5349
5350#if _LIBCPP_STD_VER > 14
5351    _LIBCPP_INLINE_VISIBILITY
5352    weak_ptr<_Tp> weak_from_this() _NOEXCEPT
5353       { return __weak_this_; }
5354
5355    _LIBCPP_INLINE_VISIBILITY
5356    weak_ptr<const _Tp> weak_from_this() const _NOEXCEPT
5357        { return __weak_this_; }
5358#endif // _LIBCPP_STD_VER > 14
5359
5360    template <class _Up> friend class shared_ptr;
5361};
5362
5363template <class _Tp>
5364struct _LIBCPP_TEMPLATE_VIS hash<shared_ptr<_Tp> >
5365{
5366    typedef shared_ptr<_Tp>      argument_type;
5367    typedef size_t               result_type;
5368
5369    _LIBCPP_INLINE_VISIBILITY
5370    result_type operator()(const argument_type& __ptr) const _NOEXCEPT
5371    {
5372        return hash<_Tp*>()(__ptr.get());
5373    }
5374};
5375
5376template<class _CharT, class _Traits, class _Yp>
5377inline _LIBCPP_INLINE_VISIBILITY
5378basic_ostream<_CharT, _Traits>&
5379operator<<(basic_ostream<_CharT, _Traits>& __os, shared_ptr<_Yp> const& __p);
5380
5381
5382#if !defined(_LIBCPP_HAS_NO_ATOMIC_HEADER)
5383
5384class _LIBCPP_TYPE_VIS __sp_mut
5385{
5386    void* __lx;
5387public:
5388    void lock() _NOEXCEPT;
5389    void unlock() _NOEXCEPT;
5390
5391private:
5392    _LIBCPP_CONSTEXPR __sp_mut(void*) _NOEXCEPT;
5393    __sp_mut(const __sp_mut&);
5394    __sp_mut& operator=(const __sp_mut&);
5395
5396    friend _LIBCPP_FUNC_VIS __sp_mut& __get_sp_mut(const void*);
5397};
5398
5399_LIBCPP_FUNC_VIS _LIBCPP_AVAILABILITY_ATOMIC_SHARED_PTR
5400__sp_mut& __get_sp_mut(const void*);
5401
5402template <class _Tp>
5403inline _LIBCPP_INLINE_VISIBILITY
5404bool
5405atomic_is_lock_free(const shared_ptr<_Tp>*)
5406{
5407    return false;
5408}
5409
5410template <class _Tp>
5411_LIBCPP_AVAILABILITY_ATOMIC_SHARED_PTR
5412shared_ptr<_Tp>
5413atomic_load(const shared_ptr<_Tp>* __p)
5414{
5415    __sp_mut& __m = __get_sp_mut(__p);
5416    __m.lock();
5417    shared_ptr<_Tp> __q = *__p;
5418    __m.unlock();
5419    return __q;
5420}
5421
5422template <class _Tp>
5423inline _LIBCPP_INLINE_VISIBILITY
5424_LIBCPP_AVAILABILITY_ATOMIC_SHARED_PTR
5425shared_ptr<_Tp>
5426atomic_load_explicit(const shared_ptr<_Tp>* __p, memory_order)
5427{
5428    return atomic_load(__p);
5429}
5430
5431template <class _Tp>
5432_LIBCPP_AVAILABILITY_ATOMIC_SHARED_PTR
5433void
5434atomic_store(shared_ptr<_Tp>* __p, shared_ptr<_Tp> __r)
5435{
5436    __sp_mut& __m = __get_sp_mut(__p);
5437    __m.lock();
5438    __p->swap(__r);
5439    __m.unlock();
5440}
5441
5442template <class _Tp>
5443inline _LIBCPP_INLINE_VISIBILITY
5444_LIBCPP_AVAILABILITY_ATOMIC_SHARED_PTR
5445void
5446atomic_store_explicit(shared_ptr<_Tp>* __p, shared_ptr<_Tp> __r, memory_order)
5447{
5448    atomic_store(__p, __r);
5449}
5450
5451template <class _Tp>
5452_LIBCPP_AVAILABILITY_ATOMIC_SHARED_PTR
5453shared_ptr<_Tp>
5454atomic_exchange(shared_ptr<_Tp>* __p, shared_ptr<_Tp> __r)
5455{
5456    __sp_mut& __m = __get_sp_mut(__p);
5457    __m.lock();
5458    __p->swap(__r);
5459    __m.unlock();
5460    return __r;
5461}
5462
5463template <class _Tp>
5464inline _LIBCPP_INLINE_VISIBILITY
5465_LIBCPP_AVAILABILITY_ATOMIC_SHARED_PTR
5466shared_ptr<_Tp>
5467atomic_exchange_explicit(shared_ptr<_Tp>* __p, shared_ptr<_Tp> __r, memory_order)
5468{
5469    return atomic_exchange(__p, __r);
5470}
5471
5472template <class _Tp>
5473_LIBCPP_AVAILABILITY_ATOMIC_SHARED_PTR
5474bool
5475atomic_compare_exchange_strong(shared_ptr<_Tp>* __p, shared_ptr<_Tp>* __v, shared_ptr<_Tp> __w)
5476{
5477    shared_ptr<_Tp> __temp;
5478    __sp_mut& __m = __get_sp_mut(__p);
5479    __m.lock();
5480    if (__p->__owner_equivalent(*__v))
5481    {
5482        _VSTD::swap(__temp, *__p);
5483        *__p = __w;
5484        __m.unlock();
5485        return true;
5486    }
5487    _VSTD::swap(__temp, *__v);
5488    *__v = *__p;
5489    __m.unlock();
5490    return false;
5491}
5492
5493template <class _Tp>
5494inline _LIBCPP_INLINE_VISIBILITY
5495_LIBCPP_AVAILABILITY_ATOMIC_SHARED_PTR
5496bool
5497atomic_compare_exchange_weak(shared_ptr<_Tp>* __p, shared_ptr<_Tp>* __v, shared_ptr<_Tp> __w)
5498{
5499    return atomic_compare_exchange_strong(__p, __v, __w);
5500}
5501
5502template <class _Tp>
5503inline _LIBCPP_INLINE_VISIBILITY
5504_LIBCPP_AVAILABILITY_ATOMIC_SHARED_PTR
5505bool
5506atomic_compare_exchange_strong_explicit(shared_ptr<_Tp>* __p, shared_ptr<_Tp>* __v,
5507                                        shared_ptr<_Tp> __w, memory_order, memory_order)
5508{
5509    return atomic_compare_exchange_strong(__p, __v, __w);
5510}
5511
5512template <class _Tp>
5513inline _LIBCPP_INLINE_VISIBILITY
5514_LIBCPP_AVAILABILITY_ATOMIC_SHARED_PTR
5515bool
5516atomic_compare_exchange_weak_explicit(shared_ptr<_Tp>* __p, shared_ptr<_Tp>* __v,
5517                                      shared_ptr<_Tp> __w, memory_order, memory_order)
5518{
5519    return atomic_compare_exchange_weak(__p, __v, __w);
5520}
5521
5522#endif  // !defined(_LIBCPP_HAS_NO_ATOMIC_HEADER)
5523
5524//enum class
5525#if defined(_LIBCPP_ABI_POINTER_SAFETY_ENUM_TYPE)
5526# ifndef _LIBCPP_CXX03_LANG
5527enum class pointer_safety : unsigned char {
5528  relaxed,
5529  preferred,
5530  strict
5531};
5532# endif
5533#else
5534struct _LIBCPP_TYPE_VIS pointer_safety
5535{
5536    enum __lx
5537    {
5538        relaxed,
5539        preferred,
5540        strict
5541    };
5542
5543    __lx __v_;
5544
5545    _LIBCPP_INLINE_VISIBILITY
5546    pointer_safety() : __v_() {}
5547
5548    _LIBCPP_INLINE_VISIBILITY
5549    pointer_safety(__lx __v) : __v_(__v) {}
5550    _LIBCPP_INLINE_VISIBILITY
5551    operator int() const {return __v_;}
5552};
5553#endif
5554
5555#if !defined(_LIBCPP_ABI_POINTER_SAFETY_ENUM_TYPE) && \
5556    defined(_LIBCPP_BUILDING_LIBRARY)
5557_LIBCPP_FUNC_VIS pointer_safety get_pointer_safety() _NOEXCEPT;
5558#else
5559// This function is only offered in C++03 under ABI v1.
5560# if !defined(_LIBCPP_ABI_POINTER_SAFETY_ENUM_TYPE) || !defined(_LIBCPP_CXX03_LANG)
5561inline _LIBCPP_INLINE_VISIBILITY
5562pointer_safety get_pointer_safety() _NOEXCEPT {
5563  return pointer_safety::relaxed;
5564}
5565# endif
5566#endif
5567
5568
5569_LIBCPP_FUNC_VIS void declare_reachable(void* __p);
5570_LIBCPP_FUNC_VIS void declare_no_pointers(char* __p, size_t __n);
5571_LIBCPP_FUNC_VIS void undeclare_no_pointers(char* __p, size_t __n);
5572_LIBCPP_FUNC_VIS void* __undeclare_reachable(void* __p);
5573
5574template <class _Tp>
5575inline _LIBCPP_INLINE_VISIBILITY
5576_Tp*
5577undeclare_reachable(_Tp* __p)
5578{
5579    return static_cast<_Tp*>(__undeclare_reachable(__p));
5580}
5581
5582_LIBCPP_FUNC_VIS void* align(size_t __align, size_t __sz, void*& __ptr, size_t& __space);
5583
5584// --- Helper for container swap --
5585template <typename _Alloc>
5586inline _LIBCPP_INLINE_VISIBILITY
5587void __swap_allocator(_Alloc & __a1, _Alloc & __a2)
5588#if _LIBCPP_STD_VER >= 14
5589    _NOEXCEPT
5590#else
5591    _NOEXCEPT_(__is_nothrow_swappable<_Alloc>::value)
5592#endif
5593{
5594    __swap_allocator(__a1, __a2,
5595      integral_constant<bool, _VSTD::allocator_traits<_Alloc>::propagate_on_container_swap::value>());
5596}
5597
5598template <typename _Alloc>
5599_LIBCPP_INLINE_VISIBILITY
5600void __swap_allocator(_Alloc & __a1, _Alloc & __a2, true_type)
5601#if _LIBCPP_STD_VER >= 14
5602    _NOEXCEPT
5603#else
5604    _NOEXCEPT_(__is_nothrow_swappable<_Alloc>::value)
5605#endif
5606{
5607    using _VSTD::swap;
5608    swap(__a1, __a2);
5609}
5610
5611template <typename _Alloc>
5612inline _LIBCPP_INLINE_VISIBILITY
5613void __swap_allocator(_Alloc &, _Alloc &, false_type) _NOEXCEPT {}
5614
5615template <typename _Alloc, typename _Traits=allocator_traits<_Alloc> >
5616struct __noexcept_move_assign_container : public integral_constant<bool,
5617    _Traits::propagate_on_container_move_assignment::value
5618#if _LIBCPP_STD_VER > 14
5619        || _Traits::is_always_equal::value
5620#else
5621        && is_nothrow_move_assignable<_Alloc>::value
5622#endif
5623    > {};
5624
5625
5626#ifndef _LIBCPP_HAS_NO_VARIADICS
5627template <class _Tp, class _Alloc>
5628struct __temp_value {
5629    typedef allocator_traits<_Alloc> _Traits;
5630
5631    typename aligned_storage<sizeof(_Tp), alignof(_Tp)>::type __v;
5632    _Alloc &__a;
5633
5634    _Tp *__addr() { return reinterpret_cast<_Tp *>(addressof(__v)); }
5635    _Tp &   get() { return *__addr(); }
5636
5637    template<class... _Args>
5638    _LIBCPP_NO_CFI
5639    __temp_value(_Alloc &__alloc, _Args&& ... __args) : __a(__alloc) {
5640      _Traits::construct(__a, reinterpret_cast<_Tp*>(addressof(__v)),
5641                         _VSTD::forward<_Args>(__args)...);
5642    }
5643
5644    ~__temp_value() { _Traits::destroy(__a, __addr()); }
5645    };
5646#endif
5647
5648template<typename _Alloc, typename = void, typename = void>
5649struct __is_allocator : false_type {};
5650
5651template<typename _Alloc>
5652struct __is_allocator<_Alloc,
5653       typename __void_t<typename _Alloc::value_type>::type,
5654       typename __void_t<decltype(_VSTD::declval<_Alloc&>().allocate(size_t(0)))>::type
5655     >
5656   : true_type {};
5657
5658_LIBCPP_END_NAMESPACE_STD
5659
5660_LIBCPP_POP_MACROS
5661
5662#endif  // _LIBCPP_MEMORY
5663