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