xref: /llvm-project-15.0.7/libcxx/include/memory (revision fcef3e46)
1// -*- C++ -*-
2//===-------------------------- memory ------------------------------------===//
3//
4//                     The LLVM Compiler Infrastructure
5//
6// This file is dual licensed under the MIT and the University of Illinois Open
7// Source Licenses. See LICENSE.TXT for details.
8//
9//===----------------------------------------------------------------------===//
10
11#ifndef _LIBCPP_MEMORY
12#define _LIBCPP_MEMORY
13
14/*
15    memory synopsis
16
17namespace std
18{
19
20struct allocator_arg_t { };
21constexpr allocator_arg_t allocator_arg = allocator_arg_t();
22
23template <class T, class Alloc> struct uses_allocator;
24
25template <class Ptr>
26struct pointer_traits
27{
28    typedef Ptr pointer;
29    typedef <details> element_type;
30    typedef <details> difference_type;
31
32    template <class U> using rebind = <details>;
33
34    static pointer pointer_to(<details>);
35};
36
37template <class T>
38struct pointer_traits<T*>
39{
40    typedef T* pointer;
41    typedef T element_type;
42    typedef ptrdiff_t difference_type;
43
44    template <class U> using rebind = U*;
45
46    static pointer pointer_to(<details>) noexcept;
47};
48
49template <class Alloc>
50struct allocator_traits
51{
52    typedef Alloc                        allocator_type;
53    typedef typename allocator_type::value_type
54                                         value_type;
55
56    typedef Alloc::pointer | value_type* pointer;
57    typedef Alloc::const_pointer
58          | pointer_traits<pointer>::rebind<const value_type>
59                                         const_pointer;
60    typedef Alloc::void_pointer
61          | pointer_traits<pointer>::rebind<void>
62                                         void_pointer;
63    typedef Alloc::const_void_pointer
64          | pointer_traits<pointer>::rebind<const void>
65                                         const_void_pointer;
66    typedef Alloc::difference_type
67          | pointer_traits<pointer>::difference_type
68                                         difference_type;
69    typedef Alloc::size_type
70          | make_unsigned<difference_type>::type
71                                         size_type;
72    typedef Alloc::propagate_on_container_copy_assignment
73          | false_type                   propagate_on_container_copy_assignment;
74    typedef Alloc::propagate_on_container_move_assignment
75          | false_type                   propagate_on_container_move_assignment;
76    typedef Alloc::propagate_on_container_swap
77          | false_type                   propagate_on_container_swap;
78    typedef Alloc::is_always_equal
79          | is_empty                     is_always_equal;
80
81    template <class T> using rebind_alloc  = Alloc::rebind<U>::other | Alloc<T, Args...>;
82    template <class T> using rebind_traits = allocator_traits<rebind_alloc<T>>;
83
84    static pointer allocate(allocator_type& a, size_type n);
85    static pointer allocate(allocator_type& a, size_type n, const_void_pointer hint);
86
87    static void deallocate(allocator_type& a, pointer p, size_type n) noexcept;
88
89    template <class T, class... Args>
90        static void construct(allocator_type& a, T* p, Args&&... args);
91
92    template <class T>
93        static void destroy(allocator_type& a, T* p);
94
95    static size_type max_size(const allocator_type& a); // noexcept in C++14
96
97    static allocator_type
98        select_on_container_copy_construction(const allocator_type& a);
99};
100
101template <>
102class allocator<void>
103{
104public:
105    typedef void*                                 pointer;
106    typedef const void*                           const_pointer;
107    typedef void                                  value_type;
108
109    template <class _Up> struct rebind {typedef allocator<_Up> other;};
110};
111
112template <class T>
113class allocator
114{
115public:
116    typedef size_t                                size_type;
117    typedef ptrdiff_t                             difference_type;
118    typedef T*                                    pointer;
119    typedef const T*                              const_pointer;
120    typedef typename add_lvalue_reference<T>::type       reference;
121    typedef typename add_lvalue_reference<const T>::type const_reference;
122    typedef T                                     value_type;
123
124    template <class U> struct rebind {typedef allocator<U> other;};
125
126    allocator() noexcept;
127    allocator(const allocator&) noexcept;
128    template <class U> allocator(const allocator<U>&) noexcept;
129    ~allocator();
130    pointer address(reference x) const noexcept;
131    const_pointer address(const_reference x) const noexcept;
132    pointer allocate(size_type, allocator<void>::const_pointer hint = 0);
133    void deallocate(pointer p, size_type n) noexcept;
134    size_type max_size() const noexcept;
135    template<class U, class... Args>
136        void construct(U* p, Args&&... args);
137    template <class U>
138        void destroy(U* p);
139};
140
141template <class T, class U>
142bool operator==(const allocator<T>&, const allocator<U>&) noexcept;
143
144template <class T, class U>
145bool operator!=(const allocator<T>&, const allocator<U>&) noexcept;
146
147template <class OutputIterator, class T>
148class raw_storage_iterator
149    : public iterator<output_iterator_tag,
150                      T,                               // purposefully not C++03
151                      ptrdiff_t,                       // purposefully not C++03
152                      T*,                              // purposefully not C++03
153                      raw_storage_iterator&>           // purposefully not C++03
154{
155public:
156    explicit raw_storage_iterator(OutputIterator x);
157    raw_storage_iterator& operator*();
158    raw_storage_iterator& operator=(const T& element);
159    raw_storage_iterator& operator++();
160    raw_storage_iterator  operator++(int);
161};
162
163template <class T> pair<T*,ptrdiff_t> get_temporary_buffer(ptrdiff_t n) noexcept;
164template <class T> void               return_temporary_buffer(T* p) noexcept;
165
166template <class T> T* addressof(T& r) noexcept;
167
168template <class InputIterator, class ForwardIterator>
169ForwardIterator
170uninitialized_copy(InputIterator first, InputIterator last, ForwardIterator result);
171
172template <class InputIterator, class Size, class ForwardIterator>
173ForwardIterator
174uninitialized_copy_n(InputIterator first, Size n, ForwardIterator result);
175
176template <class ForwardIterator, class T>
177void uninitialized_fill(ForwardIterator first, ForwardIterator last, const T& x);
178
179template <class ForwardIterator, class Size, class T>
180ForwardIterator
181uninitialized_fill_n(ForwardIterator first, Size n, const T& x);
182
183template <class Y> struct auto_ptr_ref {};
184
185template<class X>
186class auto_ptr
187{
188public:
189    typedef X element_type;
190
191    explicit auto_ptr(X* p =0) throw();
192    auto_ptr(auto_ptr&) throw();
193    template<class Y> auto_ptr(auto_ptr<Y>&) throw();
194    auto_ptr& operator=(auto_ptr&) throw();
195    template<class Y> auto_ptr& operator=(auto_ptr<Y>&) throw();
196    auto_ptr& operator=(auto_ptr_ref<X> r) throw();
197    ~auto_ptr() throw();
198
199    typename add_lvalue_reference<X>::type operator*() const throw();
200    X* operator->() const throw();
201    X* get() const throw();
202    X* release() throw();
203    void reset(X* p =0) throw();
204
205    auto_ptr(auto_ptr_ref<X>) throw();
206    template<class Y> operator auto_ptr_ref<Y>() throw();
207    template<class Y> operator auto_ptr<Y>() throw();
208};
209
210template <class T>
211struct default_delete
212{
213    constexpr default_delete() noexcept = default;
214    template <class U> default_delete(const default_delete<U>&) noexcept;
215
216    void operator()(T*) const noexcept;
217};
218
219template <class T>
220struct default_delete<T[]>
221{
222    constexpr default_delete() noexcept = default;
223    void operator()(T*) const noexcept;
224    template <class U> void operator()(U*) const = delete;
225};
226
227template <class T, class D = default_delete<T>>
228class unique_ptr
229{
230public:
231    typedef see below pointer;
232    typedef T element_type;
233    typedef D deleter_type;
234
235    // constructors
236    constexpr unique_ptr() noexcept;
237    explicit unique_ptr(pointer p) noexcept;
238    unique_ptr(pointer p, see below d1) noexcept;
239    unique_ptr(pointer p, see below d2) noexcept;
240    unique_ptr(unique_ptr&& u) noexcept;
241    unique_ptr(nullptr_t) noexcept : unique_ptr() { }
242    template <class U, class E>
243        unique_ptr(unique_ptr<U, E>&& u) noexcept;
244    template <class U>
245        unique_ptr(auto_ptr<U>&& u) noexcept;
246
247    // destructor
248    ~unique_ptr();
249
250    // assignment
251    unique_ptr& operator=(unique_ptr&& u) noexcept;
252    template <class U, class E> unique_ptr& operator=(unique_ptr<U, E>&& u) noexcept;
253    unique_ptr& operator=(nullptr_t) noexcept;
254
255    // observers
256    typename add_lvalue_reference<T>::type operator*() const;
257    pointer operator->() const noexcept;
258    pointer get() const noexcept;
259    deleter_type& get_deleter() noexcept;
260    const deleter_type& get_deleter() const noexcept;
261    explicit operator bool() const noexcept;
262
263    // modifiers
264    pointer release() noexcept;
265    void reset(pointer p = pointer()) noexcept;
266    void swap(unique_ptr& u) noexcept;
267};
268
269template <class T, class D>
270class unique_ptr<T[], D>
271{
272public:
273    typedef implementation-defined pointer;
274    typedef T element_type;
275    typedef D deleter_type;
276
277    // constructors
278    constexpr unique_ptr() noexcept;
279    explicit unique_ptr(pointer p) noexcept;
280    unique_ptr(pointer p, see below d) noexcept;
281    unique_ptr(pointer p, see below d) noexcept;
282    unique_ptr(unique_ptr&& u) noexcept;
283    unique_ptr(nullptr_t) noexcept : unique_ptr() { }
284
285    // destructor
286    ~unique_ptr();
287
288    // assignment
289    unique_ptr& operator=(unique_ptr&& u) noexcept;
290    unique_ptr& operator=(nullptr_t) noexcept;
291
292    // observers
293    T& operator[](size_t i) const;
294    pointer get() const noexcept;
295    deleter_type& get_deleter() noexcept;
296    const deleter_type& get_deleter() const noexcept;
297    explicit operator bool() const noexcept;
298
299    // modifiers
300    pointer release() noexcept;
301    void reset(pointer p = pointer()) noexcept;
302    void reset(nullptr_t) noexcept;
303    template <class U> void reset(U) = delete;
304    void swap(unique_ptr& u) noexcept;
305};
306
307template <class T, class D>
308    void swap(unique_ptr<T, D>& x, unique_ptr<T, D>& y) noexcept;
309
310template <class T1, class D1, class T2, class D2>
311    bool operator==(const unique_ptr<T1, D1>& x, const unique_ptr<T2, D2>& y);
312template <class T1, class D1, class T2, class D2>
313    bool operator!=(const unique_ptr<T1, D1>& x, const unique_ptr<T2, D2>& y);
314template <class T1, class D1, class T2, class D2>
315    bool operator<(const unique_ptr<T1, D1>& x, const unique_ptr<T2, D2>& y);
316template <class T1, class D1, class T2, class D2>
317    bool operator<=(const unique_ptr<T1, D1>& x, const unique_ptr<T2, D2>& y);
318template <class T1, class D1, class T2, class D2>
319    bool operator>(const unique_ptr<T1, D1>& x, const unique_ptr<T2, D2>& y);
320template <class T1, class D1, class T2, class D2>
321    bool operator>=(const unique_ptr<T1, D1>& x, const unique_ptr<T2, D2>& y);
322
323template <class T, class D>
324    bool operator==(const unique_ptr<T, D>& x, nullptr_t) noexcept;
325template <class T, class D>
326    bool operator==(nullptr_t, const unique_ptr<T, D>& y) noexcept;
327template <class T, class D>
328    bool operator!=(const unique_ptr<T, D>& x, nullptr_t) noexcept;
329template <class T, class D>
330    bool operator!=(nullptr_t, const unique_ptr<T, D>& y) noexcept;
331
332template <class T, class D>
333    bool operator<(const unique_ptr<T, D>& x, nullptr_t);
334template <class T, class D>
335    bool operator<(nullptr_t, const unique_ptr<T, D>& y);
336template <class T, class D>
337    bool operator<=(const unique_ptr<T, D>& x, nullptr_t);
338template <class T, class D>
339    bool operator<=(nullptr_t, const unique_ptr<T, D>& y);
340template <class T, class D>
341    bool operator>(const unique_ptr<T, D>& x, nullptr_t);
342template <class T, class D>
343    bool operator>(nullptr_t, const unique_ptr<T, D>& y);
344template <class T, class D>
345    bool operator>=(const unique_ptr<T, D>& x, nullptr_t);
346template <class T, class D>
347    bool operator>=(nullptr_t, const unique_ptr<T, D>& y);
348
349class bad_weak_ptr
350    : public std::exception
351{
352    bad_weak_ptr() noexcept;
353};
354
355template<class T, class... Args> unique_ptr<T> make_unique(Args&&... args);     // C++14
356template<class T>                unique_ptr<T> make_unique(size_t n);           // C++14
357template<class T, class... Args> unspecified   make_unique(Args&&...) = delete; // C++14, T == U[N]
358
359template<class T>
360class shared_ptr
361{
362public:
363    typedef T element_type;
364
365    // constructors:
366    constexpr shared_ptr() noexcept;
367    template<class Y> explicit shared_ptr(Y* p);
368    template<class Y, class D> shared_ptr(Y* p, D d);
369    template<class Y, class D, class A> shared_ptr(Y* p, D d, A a);
370    template <class D> shared_ptr(nullptr_t p, D d);
371    template <class D, class A> shared_ptr(nullptr_t p, D d, A a);
372    template<class Y> shared_ptr(const shared_ptr<Y>& r, T *p) noexcept;
373    shared_ptr(const shared_ptr& r) noexcept;
374    template<class Y> shared_ptr(const shared_ptr<Y>& r) noexcept;
375    shared_ptr(shared_ptr&& r) noexcept;
376    template<class Y> shared_ptr(shared_ptr<Y>&& r) noexcept;
377    template<class Y> explicit shared_ptr(const weak_ptr<Y>& r);
378    template<class Y> shared_ptr(auto_ptr<Y>&& r);
379    template <class Y, class D> shared_ptr(unique_ptr<Y, D>&& r);
380    shared_ptr(nullptr_t) : shared_ptr() { }
381
382    // destructor:
383    ~shared_ptr();
384
385    // assignment:
386    shared_ptr& operator=(const shared_ptr& r) noexcept;
387    template<class Y> shared_ptr& operator=(const shared_ptr<Y>& r) noexcept;
388    shared_ptr& operator=(shared_ptr&& r) noexcept;
389    template<class Y> shared_ptr& operator=(shared_ptr<Y>&& r);
390    template<class Y> shared_ptr& operator=(auto_ptr<Y>&& r);
391    template <class Y, class D> shared_ptr& operator=(unique_ptr<Y, D>&& r);
392
393    // modifiers:
394    void swap(shared_ptr& r) noexcept;
395    void reset() noexcept;
396    template<class Y> void reset(Y* p);
397    template<class Y, class D> void reset(Y* p, D d);
398    template<class Y, class D, class A> void reset(Y* p, D d, A a);
399
400    // observers:
401    T* get() const noexcept;
402    T& operator*() const noexcept;
403    T* operator->() const noexcept;
404    long use_count() const noexcept;
405    bool unique() const noexcept;
406    explicit operator bool() const noexcept;
407    template<class U> bool owner_before(shared_ptr<U> const& b) const;
408    template<class U> bool owner_before(weak_ptr<U> const& b) const;
409};
410
411// shared_ptr comparisons:
412template<class T, class U>
413    bool operator==(shared_ptr<T> const& a, shared_ptr<U> const& b) noexcept;
414template<class T, class U>
415    bool operator!=(shared_ptr<T> const& a, shared_ptr<U> const& b) noexcept;
416template<class T, class U>
417    bool operator<(shared_ptr<T> const& a, shared_ptr<U> const& b) noexcept;
418template<class T, class U>
419    bool operator>(shared_ptr<T> const& a, shared_ptr<U> const& b) noexcept;
420template<class T, class U>
421    bool operator<=(shared_ptr<T> const& a, shared_ptr<U> const& b) noexcept;
422template<class T, class U>
423    bool operator>=(shared_ptr<T> const& a, shared_ptr<U> const& b) noexcept;
424
425template <class T>
426    bool operator==(const shared_ptr<T>& x, nullptr_t) noexcept;
427template <class T>
428    bool operator==(nullptr_t, const shared_ptr<T>& y) noexcept;
429template <class T>
430    bool operator!=(const shared_ptr<T>& x, nullptr_t) noexcept;
431template <class T>
432    bool operator!=(nullptr_t, const shared_ptr<T>& y) noexcept;
433template <class T>
434    bool operator<(const shared_ptr<T>& x, nullptr_t) noexcept;
435template <class T>
436bool operator<(nullptr_t, const shared_ptr<T>& y) noexcept;
437template <class T>
438    bool operator<=(const shared_ptr<T>& x, nullptr_t) noexcept;
439template <class T>
440    bool operator<=(nullptr_t, const shared_ptr<T>& y) noexcept;
441template <class T>
442    bool operator>(const shared_ptr<T>& x, nullptr_t) noexcept;
443template <class T>
444    bool operator>(nullptr_t, const shared_ptr<T>& y) noexcept;
445template <class T>
446    bool operator>=(const shared_ptr<T>& x, nullptr_t) noexcept;
447template <class T>
448    bool operator>=(nullptr_t, const shared_ptr<T>& y) noexcept;
449
450// shared_ptr specialized algorithms:
451template<class T> void swap(shared_ptr<T>& a, shared_ptr<T>& b) noexcept;
452
453// shared_ptr casts:
454template<class T, class U>
455    shared_ptr<T> static_pointer_cast(shared_ptr<U> const& r) noexcept;
456template<class T, class U>
457    shared_ptr<T> dynamic_pointer_cast(shared_ptr<U> const& r) noexcept;
458template<class T, class U>
459    shared_ptr<T> const_pointer_cast(shared_ptr<U> const& r) noexcept;
460
461// shared_ptr I/O:
462template<class E, class T, class Y>
463    basic_ostream<E, T>& operator<< (basic_ostream<E, T>& os, shared_ptr<Y> const& p);
464
465// shared_ptr get_deleter:
466template<class D, class T> D* get_deleter(shared_ptr<T> const& p) noexcept;
467
468template<class T, class... Args>
469    shared_ptr<T> make_shared(Args&&... args);
470template<class T, class A, class... Args>
471    shared_ptr<T> allocate_shared(const A& a, Args&&... args);
472
473template<class T>
474class weak_ptr
475{
476public:
477    typedef T element_type;
478
479    // constructors
480    constexpr weak_ptr() noexcept;
481    template<class Y> weak_ptr(shared_ptr<Y> const& r) noexcept;
482    weak_ptr(weak_ptr const& r) noexcept;
483    template<class Y> weak_ptr(weak_ptr<Y> const& r) noexcept;
484    weak_ptr(weak_ptr&& r) noexcept;                      // C++14
485    template<class Y> weak_ptr(weak_ptr<Y>&& r) noexcept; // C++14
486
487    // destructor
488    ~weak_ptr();
489
490    // assignment
491    weak_ptr& operator=(weak_ptr const& r) noexcept;
492    template<class Y> weak_ptr& operator=(weak_ptr<Y> const& r) noexcept;
493    template<class Y> weak_ptr& operator=(shared_ptr<Y> const& r) noexcept;
494    weak_ptr& operator=(weak_ptr&& r) noexcept;                      // C++14
495    template<class Y> weak_ptr& operator=(weak_ptr<Y>&& r) noexcept; // C++14
496
497    // modifiers
498    void swap(weak_ptr& r) noexcept;
499    void reset() noexcept;
500
501    // observers
502    long use_count() const noexcept;
503    bool expired() const noexcept;
504    shared_ptr<T> lock() const noexcept;
505    template<class U> bool owner_before(shared_ptr<U> const& b) const;
506    template<class U> bool owner_before(weak_ptr<U> const& b) const;
507};
508
509// weak_ptr specialized algorithms:
510template<class T> void swap(weak_ptr<T>& a, weak_ptr<T>& b) noexcept;
511
512// class owner_less:
513template<class T> struct owner_less;
514
515template<class T>
516struct owner_less<shared_ptr<T>>
517    : binary_function<shared_ptr<T>, shared_ptr<T>, bool>
518{
519    typedef bool result_type;
520    bool operator()(shared_ptr<T> const&, shared_ptr<T> const&) const;
521    bool operator()(shared_ptr<T> const&, weak_ptr<T> const&) const;
522    bool operator()(weak_ptr<T> const&, shared_ptr<T> const&) const;
523};
524
525template<class T>
526struct owner_less<weak_ptr<T>>
527    : binary_function<weak_ptr<T>, weak_ptr<T>, bool>
528{
529    typedef bool result_type;
530    bool operator()(weak_ptr<T> const&, weak_ptr<T> const&) const;
531    bool operator()(shared_ptr<T> const&, weak_ptr<T> const&) const;
532    bool operator()(weak_ptr<T> const&, shared_ptr<T> const&) const;
533};
534
535template<class T>
536class enable_shared_from_this
537{
538protected:
539    constexpr enable_shared_from_this() noexcept;
540    enable_shared_from_this(enable_shared_from_this const&) noexcept;
541    enable_shared_from_this& operator=(enable_shared_from_this const&) noexcept;
542    ~enable_shared_from_this();
543public:
544    shared_ptr<T> shared_from_this();
545    shared_ptr<T const> shared_from_this() const;
546};
547
548template<class T>
549    bool atomic_is_lock_free(const shared_ptr<T>* p);
550template<class T>
551    shared_ptr<T> atomic_load(const shared_ptr<T>* p);
552template<class T>
553    shared_ptr<T> atomic_load_explicit(const shared_ptr<T>* p, memory_order mo);
554template<class T>
555    void atomic_store(shared_ptr<T>* p, shared_ptr<T> r);
556template<class T>
557    void atomic_store_explicit(shared_ptr<T>* p, shared_ptr<T> r, memory_order mo);
558template<class T>
559    shared_ptr<T> atomic_exchange(shared_ptr<T>* p, shared_ptr<T> r);
560template<class T>
561    shared_ptr<T>
562    atomic_exchange_explicit(shared_ptr<T>* p, shared_ptr<T> r, memory_order mo);
563template<class T>
564    bool
565    atomic_compare_exchange_weak(shared_ptr<T>* p, shared_ptr<T>* v, shared_ptr<T> w);
566template<class T>
567    bool
568    atomic_compare_exchange_strong( shared_ptr<T>* p, shared_ptr<T>* v, shared_ptr<T> w);
569template<class T>
570    bool
571    atomic_compare_exchange_weak_explicit(shared_ptr<T>* p, shared_ptr<T>* v,
572                                          shared_ptr<T> w, memory_order success,
573                                          memory_order failure);
574template<class T>
575    bool
576    atomic_compare_exchange_strong_explicit(shared_ptr<T>* p, shared_ptr<T>* v,
577                                            shared_ptr<T> w, memory_order success,
578                                            memory_order failure);
579// Hash support
580template <class T> struct hash;
581template <class T, class D> struct hash<unique_ptr<T, D> >;
582template <class T> struct hash<shared_ptr<T> >;
583
584// Pointer safety
585enum class pointer_safety { relaxed, preferred, strict };
586void declare_reachable(void *p);
587template <class T> T *undeclare_reachable(T *p);
588void declare_no_pointers(char *p, size_t n);
589void undeclare_no_pointers(char *p, size_t n);
590pointer_safety get_pointer_safety() noexcept;
591
592void* align(size_t alignment, size_t size, void*& ptr, size_t& space);
593
594}  // std
595
596*/
597
598#include <__config>
599#include <type_traits>
600#include <typeinfo>
601#include <cstddef>
602#include <cstdint>
603#include <new>
604#include <utility>
605#include <limits>
606#include <iterator>
607#include <__functional_base>
608#include <iosfwd>
609#include <tuple>
610#include <cstring>
611#if defined(_LIBCPP_NO_EXCEPTIONS)
612    #include <cassert>
613#endif
614
615#if !defined(_LIBCPP_HAS_NO_ATOMIC_HEADER)
616#  include <atomic>
617#endif
618
619#include <__undef_min_max>
620#include <__undef___deallocate>
621
622#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
623#pragma GCC system_header
624#endif
625
626_LIBCPP_BEGIN_NAMESPACE_STD
627
628template <class _ValueType>
629inline _LIBCPP_ALWAYS_INLINE
630_ValueType __libcpp_relaxed_load(_ValueType const* __value) {
631#if !defined(_LIBCPP_HAS_NO_THREADS) && \
632    defined(__ATOMIC_RELAXED) &&        \
633    (__has_builtin(__atomic_load_n) || _GNUC_VER >= 407)
634    return __atomic_load_n(__value, __ATOMIC_RELAXED);
635#else
636    return *__value;
637#endif
638}
639
640// addressof moved to <__functional_base>
641
642template <class _Tp> class allocator;
643
644template <>
645class _LIBCPP_TYPE_VIS_ONLY allocator<void>
646{
647public:
648    typedef void*             pointer;
649    typedef const void*       const_pointer;
650    typedef void              value_type;
651
652    template <class _Up> struct rebind {typedef allocator<_Up> other;};
653};
654
655template <>
656class _LIBCPP_TYPE_VIS_ONLY allocator<const void>
657{
658public:
659    typedef const void*       pointer;
660    typedef const void*       const_pointer;
661    typedef const void        value_type;
662
663    template <class _Up> struct rebind {typedef allocator<_Up> other;};
664};
665
666// pointer_traits
667
668template <class _Tp>
669struct __has_element_type
670{
671private:
672    struct __two {char __lx; char __lxx;};
673    template <class _Up> static __two __test(...);
674    template <class _Up> static char __test(typename _Up::element_type* = 0);
675public:
676    static const bool value = sizeof(__test<_Tp>(0)) == 1;
677};
678
679template <class _Ptr, bool = __has_element_type<_Ptr>::value>
680struct __pointer_traits_element_type;
681
682template <class _Ptr>
683struct __pointer_traits_element_type<_Ptr, true>
684{
685    typedef typename _Ptr::element_type type;
686};
687
688#ifndef _LIBCPP_HAS_NO_VARIADICS
689
690template <template <class, class...> class _Sp, class _Tp, class ..._Args>
691struct __pointer_traits_element_type<_Sp<_Tp, _Args...>, true>
692{
693    typedef typename _Sp<_Tp, _Args...>::element_type type;
694};
695
696template <template <class, class...> class _Sp, class _Tp, class ..._Args>
697struct __pointer_traits_element_type<_Sp<_Tp, _Args...>, false>
698{
699    typedef _Tp type;
700};
701
702#else  // _LIBCPP_HAS_NO_VARIADICS
703
704template <template <class> class _Sp, class _Tp>
705struct __pointer_traits_element_type<_Sp<_Tp>, true>
706{
707    typedef typename _Sp<_Tp>::element_type type;
708};
709
710template <template <class> class _Sp, class _Tp>
711struct __pointer_traits_element_type<_Sp<_Tp>, false>
712{
713    typedef _Tp type;
714};
715
716template <template <class, class> class _Sp, class _Tp, class _A0>
717struct __pointer_traits_element_type<_Sp<_Tp, _A0>, true>
718{
719    typedef typename _Sp<_Tp, _A0>::element_type type;
720};
721
722template <template <class, class> class _Sp, class _Tp, class _A0>
723struct __pointer_traits_element_type<_Sp<_Tp, _A0>, false>
724{
725    typedef _Tp type;
726};
727
728template <template <class, class, class> class _Sp, class _Tp, class _A0, class _A1>
729struct __pointer_traits_element_type<_Sp<_Tp, _A0, _A1>, true>
730{
731    typedef typename _Sp<_Tp, _A0, _A1>::element_type type;
732};
733
734template <template <class, class, class> class _Sp, class _Tp, class _A0, class _A1>
735struct __pointer_traits_element_type<_Sp<_Tp, _A0, _A1>, false>
736{
737    typedef _Tp type;
738};
739
740template <template <class, class, class, class> class _Sp, class _Tp, class _A0,
741                                                           class _A1, class _A2>
742struct __pointer_traits_element_type<_Sp<_Tp, _A0, _A1, _A2>, true>
743{
744    typedef typename _Sp<_Tp, _A0, _A1, _A2>::element_type type;
745};
746
747template <template <class, class, class, class> class _Sp, class _Tp, class _A0,
748                                                           class _A1, class _A2>
749struct __pointer_traits_element_type<_Sp<_Tp, _A0, _A1, _A2>, false>
750{
751    typedef _Tp type;
752};
753
754#endif  // _LIBCPP_HAS_NO_VARIADICS
755
756template <class _Tp>
757struct __has_difference_type
758{
759private:
760    struct __two {char __lx; char __lxx;};
761    template <class _Up> static __two __test(...);
762    template <class _Up> static char __test(typename _Up::difference_type* = 0);
763public:
764    static const bool value = sizeof(__test<_Tp>(0)) == 1;
765};
766
767template <class _Ptr, bool = __has_difference_type<_Ptr>::value>
768struct __pointer_traits_difference_type
769{
770    typedef ptrdiff_t type;
771};
772
773template <class _Ptr>
774struct __pointer_traits_difference_type<_Ptr, true>
775{
776    typedef typename _Ptr::difference_type type;
777};
778
779template <class _Tp, class _Up>
780struct __has_rebind
781{
782private:
783    struct __two {char __lx; char __lxx;};
784    template <class _Xp> static __two __test(...);
785    template <class _Xp> static char __test(typename _Xp::template rebind<_Up>* = 0);
786public:
787    static const bool value = sizeof(__test<_Tp>(0)) == 1;
788};
789
790template <class _Tp, class _Up, bool = __has_rebind<_Tp, _Up>::value>
791struct __pointer_traits_rebind
792{
793#ifndef _LIBCPP_HAS_NO_TEMPLATE_ALIASES
794    typedef typename _Tp::template rebind<_Up> type;
795#else
796    typedef typename _Tp::template rebind<_Up>::other type;
797#endif
798};
799
800#ifndef _LIBCPP_HAS_NO_VARIADICS
801
802template <template <class, class...> class _Sp, class _Tp, class ..._Args, class _Up>
803struct __pointer_traits_rebind<_Sp<_Tp, _Args...>, _Up, true>
804{
805#ifndef _LIBCPP_HAS_NO_TEMPLATE_ALIASES
806    typedef typename _Sp<_Tp, _Args...>::template rebind<_Up> type;
807#else
808    typedef typename _Sp<_Tp, _Args...>::template rebind<_Up>::other type;
809#endif
810};
811
812template <template <class, class...> class _Sp, class _Tp, class ..._Args, class _Up>
813struct __pointer_traits_rebind<_Sp<_Tp, _Args...>, _Up, false>
814{
815    typedef _Sp<_Up, _Args...> type;
816};
817
818#else  // _LIBCPP_HAS_NO_VARIADICS
819
820template <template <class> class _Sp, class _Tp, class _Up>
821struct __pointer_traits_rebind<_Sp<_Tp>, _Up, true>
822{
823#ifndef _LIBCPP_HAS_NO_TEMPLATE_ALIASES
824    typedef typename _Sp<_Tp>::template rebind<_Up> type;
825#else
826    typedef typename _Sp<_Tp>::template rebind<_Up>::other type;
827#endif
828};
829
830template <template <class> class _Sp, class _Tp, class _Up>
831struct __pointer_traits_rebind<_Sp<_Tp>, _Up, false>
832{
833    typedef _Sp<_Up> type;
834};
835
836template <template <class, class> class _Sp, class _Tp, class _A0, class _Up>
837struct __pointer_traits_rebind<_Sp<_Tp, _A0>, _Up, true>
838{
839#ifndef _LIBCPP_HAS_NO_TEMPLATE_ALIASES
840    typedef typename _Sp<_Tp, _A0>::template rebind<_Up> type;
841#else
842    typedef typename _Sp<_Tp, _A0>::template rebind<_Up>::other type;
843#endif
844};
845
846template <template <class, class> class _Sp, class _Tp, class _A0, class _Up>
847struct __pointer_traits_rebind<_Sp<_Tp, _A0>, _Up, false>
848{
849    typedef _Sp<_Up, _A0> type;
850};
851
852template <template <class, class, class> class _Sp, class _Tp, class _A0,
853                                         class _A1, class _Up>
854struct __pointer_traits_rebind<_Sp<_Tp, _A0, _A1>, _Up, true>
855{
856#ifndef _LIBCPP_HAS_NO_TEMPLATE_ALIASES
857    typedef typename _Sp<_Tp, _A0, _A1>::template rebind<_Up> type;
858#else
859    typedef typename _Sp<_Tp, _A0, _A1>::template rebind<_Up>::other type;
860#endif
861};
862
863template <template <class, class, class> class _Sp, class _Tp, class _A0,
864                                         class _A1, class _Up>
865struct __pointer_traits_rebind<_Sp<_Tp, _A0, _A1>, _Up, false>
866{
867    typedef _Sp<_Up, _A0, _A1> type;
868};
869
870template <template <class, class, class, class> class _Sp, class _Tp, class _A0,
871                                                class _A1, class _A2, class _Up>
872struct __pointer_traits_rebind<_Sp<_Tp, _A0, _A1, _A2>, _Up, true>
873{
874#ifndef _LIBCPP_HAS_NO_TEMPLATE_ALIASES
875    typedef typename _Sp<_Tp, _A0, _A1, _A2>::template rebind<_Up> type;
876#else
877    typedef typename _Sp<_Tp, _A0, _A1, _A2>::template rebind<_Up>::other type;
878#endif
879};
880
881template <template <class, class, class, class> class _Sp, class _Tp, class _A0,
882                                                class _A1, class _A2, class _Up>
883struct __pointer_traits_rebind<_Sp<_Tp, _A0, _A1, _A2>, _Up, false>
884{
885    typedef _Sp<_Up, _A0, _A1, _A2> type;
886};
887
888#endif  // _LIBCPP_HAS_NO_VARIADICS
889
890template <class _Ptr>
891struct _LIBCPP_TYPE_VIS_ONLY pointer_traits
892{
893    typedef _Ptr                                                     pointer;
894    typedef typename __pointer_traits_element_type<pointer>::type    element_type;
895    typedef typename __pointer_traits_difference_type<pointer>::type difference_type;
896
897#ifndef _LIBCPP_HAS_NO_TEMPLATE_ALIASES
898    template <class _Up> using rebind = typename __pointer_traits_rebind<pointer, _Up>::type;
899#else
900    template <class _Up> struct rebind
901        {typedef typename __pointer_traits_rebind<pointer, _Up>::type other;};
902#endif  // _LIBCPP_HAS_NO_TEMPLATE_ALIASES
903
904private:
905    struct __nat {};
906public:
907    _LIBCPP_INLINE_VISIBILITY
908    static pointer pointer_to(typename conditional<is_void<element_type>::value,
909                                           __nat, element_type>::type& __r)
910        {return pointer::pointer_to(__r);}
911};
912
913template <class _Tp>
914struct _LIBCPP_TYPE_VIS_ONLY pointer_traits<_Tp*>
915{
916    typedef _Tp*      pointer;
917    typedef _Tp       element_type;
918    typedef ptrdiff_t difference_type;
919
920#ifndef _LIBCPP_HAS_NO_TEMPLATE_ALIASES
921    template <class _Up> using rebind = _Up*;
922#else
923    template <class _Up> struct rebind {typedef _Up* other;};
924#endif
925
926private:
927    struct __nat {};
928public:
929    _LIBCPP_INLINE_VISIBILITY
930    static pointer pointer_to(typename conditional<is_void<element_type>::value,
931                                      __nat, element_type>::type& __r) _NOEXCEPT
932        {return _VSTD::addressof(__r);}
933};
934
935template <class _From, class _To>
936struct __rebind_pointer {
937#ifndef _LIBCPP_HAS_NO_TEMPLATE_ALIASES
938    typedef typename pointer_traits<_From>::template rebind<_To>        type;
939#else
940    typedef typename pointer_traits<_From>::template rebind<_To>::other type;
941#endif
942};
943
944// allocator_traits
945
946namespace __has_pointer_type_imp
947{
948    template <class _Up> static __two __test(...);
949    template <class _Up> static char __test(typename _Up::pointer* = 0);
950}
951
952template <class _Tp>
953struct __has_pointer_type
954    : public integral_constant<bool, sizeof(__has_pointer_type_imp::__test<_Tp>(0)) == 1>
955{
956};
957
958namespace __pointer_type_imp
959{
960
961template <class _Tp, class _Dp, bool = __has_pointer_type<_Dp>::value>
962struct __pointer_type
963{
964    typedef typename _Dp::pointer type;
965};
966
967template <class _Tp, class _Dp>
968struct __pointer_type<_Tp, _Dp, false>
969{
970    typedef _Tp* type;
971};
972
973}  // __pointer_type_imp
974
975template <class _Tp, class _Dp>
976struct __pointer_type
977{
978    typedef typename __pointer_type_imp::__pointer_type<_Tp, typename remove_reference<_Dp>::type>::type type;
979};
980
981template <class _Tp>
982struct __has_const_pointer
983{
984private:
985    struct __two {char __lx; char __lxx;};
986    template <class _Up> static __two __test(...);
987    template <class _Up> static char __test(typename _Up::const_pointer* = 0);
988public:
989    static const bool value = sizeof(__test<_Tp>(0)) == 1;
990};
991
992template <class _Tp, class _Ptr, class _Alloc, bool = __has_const_pointer<_Alloc>::value>
993struct __const_pointer
994{
995    typedef typename _Alloc::const_pointer type;
996};
997
998template <class _Tp, class _Ptr, class _Alloc>
999struct __const_pointer<_Tp, _Ptr, _Alloc, false>
1000{
1001#ifndef _LIBCPP_HAS_NO_TEMPLATE_ALIASES
1002    typedef typename pointer_traits<_Ptr>::template rebind<const _Tp> type;
1003#else
1004    typedef typename pointer_traits<_Ptr>::template rebind<const _Tp>::other type;
1005#endif
1006};
1007
1008template <class _Tp>
1009struct __has_void_pointer
1010{
1011private:
1012    struct __two {char __lx; char __lxx;};
1013    template <class _Up> static __two __test(...);
1014    template <class _Up> static char __test(typename _Up::void_pointer* = 0);
1015public:
1016    static const bool value = sizeof(__test<_Tp>(0)) == 1;
1017};
1018
1019template <class _Ptr, class _Alloc, bool = __has_void_pointer<_Alloc>::value>
1020struct __void_pointer
1021{
1022    typedef typename _Alloc::void_pointer type;
1023};
1024
1025template <class _Ptr, class _Alloc>
1026struct __void_pointer<_Ptr, _Alloc, false>
1027{
1028#ifndef _LIBCPP_HAS_NO_TEMPLATE_ALIASES
1029    typedef typename pointer_traits<_Ptr>::template rebind<void> type;
1030#else
1031    typedef typename pointer_traits<_Ptr>::template rebind<void>::other type;
1032#endif
1033};
1034
1035template <class _Tp>
1036struct __has_const_void_pointer
1037{
1038private:
1039    struct __two {char __lx; char __lxx;};
1040    template <class _Up> static __two __test(...);
1041    template <class _Up> static char __test(typename _Up::const_void_pointer* = 0);
1042public:
1043    static const bool value = sizeof(__test<_Tp>(0)) == 1;
1044};
1045
1046template <class _Ptr, class _Alloc, bool = __has_const_void_pointer<_Alloc>::value>
1047struct __const_void_pointer
1048{
1049    typedef typename _Alloc::const_void_pointer type;
1050};
1051
1052template <class _Ptr, class _Alloc>
1053struct __const_void_pointer<_Ptr, _Alloc, false>
1054{
1055#ifndef _LIBCPP_HAS_NO_TEMPLATE_ALIASES
1056    typedef typename pointer_traits<_Ptr>::template rebind<const void> type;
1057#else
1058    typedef typename pointer_traits<_Ptr>::template rebind<const void>::other type;
1059#endif
1060};
1061
1062template <class _Tp>
1063inline _LIBCPP_INLINE_VISIBILITY
1064_Tp*
1065__to_raw_pointer(_Tp* __p) _NOEXCEPT
1066{
1067    return __p;
1068}
1069
1070template <class _Pointer>
1071inline _LIBCPP_INLINE_VISIBILITY
1072typename pointer_traits<_Pointer>::element_type*
1073__to_raw_pointer(_Pointer __p) _NOEXCEPT
1074{
1075    return _VSTD::__to_raw_pointer(__p.operator->());
1076}
1077
1078template <class _Tp>
1079struct __has_size_type
1080{
1081private:
1082    struct __two {char __lx; char __lxx;};
1083    template <class _Up> static __two __test(...);
1084    template <class _Up> static char __test(typename _Up::size_type* = 0);
1085public:
1086    static const bool value = sizeof(__test<_Tp>(0)) == 1;
1087};
1088
1089template <class _Alloc, class _DiffType, bool = __has_size_type<_Alloc>::value>
1090struct __size_type
1091{
1092    typedef typename make_unsigned<_DiffType>::type type;
1093};
1094
1095template <class _Alloc, class _DiffType>
1096struct __size_type<_Alloc, _DiffType, true>
1097{
1098    typedef typename _Alloc::size_type type;
1099};
1100
1101template <class _Tp>
1102struct __has_propagate_on_container_copy_assignment
1103{
1104private:
1105    struct __two {char __lx; char __lxx;};
1106    template <class _Up> static __two __test(...);
1107    template <class _Up> static char __test(typename _Up::propagate_on_container_copy_assignment* = 0);
1108public:
1109    static const bool value = sizeof(__test<_Tp>(0)) == 1;
1110};
1111
1112template <class _Alloc, bool = __has_propagate_on_container_copy_assignment<_Alloc>::value>
1113struct __propagate_on_container_copy_assignment
1114{
1115    typedef false_type type;
1116};
1117
1118template <class _Alloc>
1119struct __propagate_on_container_copy_assignment<_Alloc, true>
1120{
1121    typedef typename _Alloc::propagate_on_container_copy_assignment type;
1122};
1123
1124template <class _Tp>
1125struct __has_propagate_on_container_move_assignment
1126{
1127private:
1128    struct __two {char __lx; char __lxx;};
1129    template <class _Up> static __two __test(...);
1130    template <class _Up> static char __test(typename _Up::propagate_on_container_move_assignment* = 0);
1131public:
1132    static const bool value = sizeof(__test<_Tp>(0)) == 1;
1133};
1134
1135template <class _Alloc, bool = __has_propagate_on_container_move_assignment<_Alloc>::value>
1136struct __propagate_on_container_move_assignment
1137{
1138    typedef false_type type;
1139};
1140
1141template <class _Alloc>
1142struct __propagate_on_container_move_assignment<_Alloc, true>
1143{
1144    typedef typename _Alloc::propagate_on_container_move_assignment type;
1145};
1146
1147template <class _Tp>
1148struct __has_propagate_on_container_swap
1149{
1150private:
1151    struct __two {char __lx; char __lxx;};
1152    template <class _Up> static __two __test(...);
1153    template <class _Up> static char __test(typename _Up::propagate_on_container_swap* = 0);
1154public:
1155    static const bool value = sizeof(__test<_Tp>(0)) == 1;
1156};
1157
1158template <class _Alloc, bool = __has_propagate_on_container_swap<_Alloc>::value>
1159struct __propagate_on_container_swap
1160{
1161    typedef false_type type;
1162};
1163
1164template <class _Alloc>
1165struct __propagate_on_container_swap<_Alloc, true>
1166{
1167    typedef typename _Alloc::propagate_on_container_swap type;
1168};
1169
1170template <class _Tp>
1171struct __has_is_always_equal
1172{
1173private:
1174    struct __two {char __lx; char __lxx;};
1175    template <class _Up> static __two __test(...);
1176    template <class _Up> static char __test(typename _Up::is_always_equal* = 0);
1177public:
1178    static const bool value = sizeof(__test<_Tp>(0)) == 1;
1179};
1180
1181template <class _Alloc, bool = __has_is_always_equal<_Alloc>::value>
1182struct __is_always_equal
1183{
1184    typedef typename _VSTD::is_empty<_Alloc>::type type;
1185};
1186
1187template <class _Alloc>
1188struct __is_always_equal<_Alloc, true>
1189{
1190    typedef typename _Alloc::is_always_equal type;
1191};
1192
1193template <class _Tp, class _Up, bool = __has_rebind<_Tp, _Up>::value>
1194struct __has_rebind_other
1195{
1196private:
1197    struct __two {char __lx; char __lxx;};
1198    template <class _Xp> static __two __test(...);
1199    template <class _Xp> static char __test(typename _Xp::template rebind<_Up>::other* = 0);
1200public:
1201    static const bool value = sizeof(__test<_Tp>(0)) == 1;
1202};
1203
1204template <class _Tp, class _Up>
1205struct __has_rebind_other<_Tp, _Up, false>
1206{
1207    static const bool value = false;
1208};
1209
1210template <class _Tp, class _Up, bool = __has_rebind_other<_Tp, _Up>::value>
1211struct __allocator_traits_rebind
1212{
1213    typedef typename _Tp::template rebind<_Up>::other type;
1214};
1215
1216#ifndef _LIBCPP_HAS_NO_VARIADICS
1217
1218template <template <class, class...> class _Alloc, class _Tp, class ..._Args, class _Up>
1219struct __allocator_traits_rebind<_Alloc<_Tp, _Args...>, _Up, true>
1220{
1221    typedef typename _Alloc<_Tp, _Args...>::template rebind<_Up>::other type;
1222};
1223
1224template <template <class, class...> class _Alloc, class _Tp, class ..._Args, class _Up>
1225struct __allocator_traits_rebind<_Alloc<_Tp, _Args...>, _Up, false>
1226{
1227    typedef _Alloc<_Up, _Args...> type;
1228};
1229
1230#else  // _LIBCPP_HAS_NO_VARIADICS
1231
1232template <template <class> class _Alloc, class _Tp, class _Up>
1233struct __allocator_traits_rebind<_Alloc<_Tp>, _Up, true>
1234{
1235    typedef typename _Alloc<_Tp>::template rebind<_Up>::other type;
1236};
1237
1238template <template <class> class _Alloc, class _Tp, class _Up>
1239struct __allocator_traits_rebind<_Alloc<_Tp>, _Up, false>
1240{
1241    typedef _Alloc<_Up> type;
1242};
1243
1244template <template <class, class> class _Alloc, class _Tp, class _A0, class _Up>
1245struct __allocator_traits_rebind<_Alloc<_Tp, _A0>, _Up, true>
1246{
1247    typedef typename _Alloc<_Tp, _A0>::template rebind<_Up>::other type;
1248};
1249
1250template <template <class, class> class _Alloc, class _Tp, class _A0, class _Up>
1251struct __allocator_traits_rebind<_Alloc<_Tp, _A0>, _Up, false>
1252{
1253    typedef _Alloc<_Up, _A0> type;
1254};
1255
1256template <template <class, class, class> class _Alloc, class _Tp, class _A0,
1257                                         class _A1, class _Up>
1258struct __allocator_traits_rebind<_Alloc<_Tp, _A0, _A1>, _Up, true>
1259{
1260    typedef typename _Alloc<_Tp, _A0, _A1>::template rebind<_Up>::other type;
1261};
1262
1263template <template <class, class, class> class _Alloc, class _Tp, class _A0,
1264                                         class _A1, class _Up>
1265struct __allocator_traits_rebind<_Alloc<_Tp, _A0, _A1>, _Up, false>
1266{
1267    typedef _Alloc<_Up, _A0, _A1> type;
1268};
1269
1270template <template <class, class, class, class> class _Alloc, class _Tp, class _A0,
1271                                                class _A1, class _A2, class _Up>
1272struct __allocator_traits_rebind<_Alloc<_Tp, _A0, _A1, _A2>, _Up, true>
1273{
1274    typedef typename _Alloc<_Tp, _A0, _A1, _A2>::template rebind<_Up>::other type;
1275};
1276
1277template <template <class, class, class, class> class _Alloc, class _Tp, class _A0,
1278                                                class _A1, class _A2, class _Up>
1279struct __allocator_traits_rebind<_Alloc<_Tp, _A0, _A1, _A2>, _Up, false>
1280{
1281    typedef _Alloc<_Up, _A0, _A1, _A2> type;
1282};
1283
1284#endif  // _LIBCPP_HAS_NO_VARIADICS
1285
1286#ifndef _LIBCPP_HAS_NO_ADVANCED_SFINAE
1287
1288template <class _Alloc, class _SizeType, class _ConstVoidPtr>
1289auto
1290__has_allocate_hint_test(_Alloc&& __a, _SizeType&& __sz, _ConstVoidPtr&& __p)
1291    -> decltype(__a.allocate(__sz, __p), true_type());
1292
1293template <class _Alloc, class _SizeType, class _ConstVoidPtr>
1294auto
1295__has_allocate_hint_test(const _Alloc& __a, _SizeType&& __sz, _ConstVoidPtr&& __p)
1296    -> false_type;
1297
1298template <class _Alloc, class _SizeType, class _ConstVoidPtr>
1299struct __has_allocate_hint
1300    : integral_constant<bool,
1301        is_same<
1302            decltype(__has_allocate_hint_test(declval<_Alloc>(),
1303                                          declval<_SizeType>(),
1304                                          declval<_ConstVoidPtr>())),
1305            true_type>::value>
1306{
1307};
1308
1309#else  // _LIBCPP_HAS_NO_ADVANCED_SFINAE
1310
1311template <class _Alloc, class _SizeType, class _ConstVoidPtr>
1312struct __has_allocate_hint
1313    : true_type
1314{
1315};
1316
1317#endif  // _LIBCPP_HAS_NO_ADVANCED_SFINAE
1318
1319#if !defined(_LIBCPP_HAS_NO_ADVANCED_SFINAE) && !defined(_LIBCPP_HAS_NO_VARIADICS)
1320
1321template <class _Alloc, class _Tp, class ..._Args>
1322decltype(_VSTD::declval<_Alloc>().construct(_VSTD::declval<_Tp*>(),
1323                                           _VSTD::declval<_Args>()...),
1324                                           true_type())
1325__has_construct_test(_Alloc&& __a, _Tp* __p, _Args&& ...__args);
1326
1327template <class _Alloc, class _Pointer, class ..._Args>
1328false_type
1329__has_construct_test(const _Alloc& __a, _Pointer&& __p, _Args&& ...__args);
1330
1331template <class _Alloc, class _Pointer, class ..._Args>
1332struct __has_construct
1333    : integral_constant<bool,
1334        is_same<
1335            decltype(__has_construct_test(declval<_Alloc>(),
1336                                          declval<_Pointer>(),
1337                                          declval<_Args>()...)),
1338            true_type>::value>
1339{
1340};
1341
1342template <class _Alloc, class _Pointer>
1343auto
1344__has_destroy_test(_Alloc&& __a, _Pointer&& __p)
1345    -> decltype(__a.destroy(__p), true_type());
1346
1347template <class _Alloc, class _Pointer>
1348auto
1349__has_destroy_test(const _Alloc& __a, _Pointer&& __p)
1350    -> false_type;
1351
1352template <class _Alloc, class _Pointer>
1353struct __has_destroy
1354    : integral_constant<bool,
1355        is_same<
1356            decltype(__has_destroy_test(declval<_Alloc>(),
1357                                        declval<_Pointer>())),
1358            true_type>::value>
1359{
1360};
1361
1362template <class _Alloc>
1363auto
1364__has_max_size_test(_Alloc&& __a)
1365    -> decltype(__a.max_size(), true_type());
1366
1367template <class _Alloc>
1368auto
1369__has_max_size_test(const volatile _Alloc& __a)
1370    -> false_type;
1371
1372template <class _Alloc>
1373struct __has_max_size
1374    : integral_constant<bool,
1375        is_same<
1376            decltype(__has_max_size_test(declval<_Alloc&>())),
1377            true_type>::value>
1378{
1379};
1380
1381template <class _Alloc>
1382auto
1383__has_select_on_container_copy_construction_test(_Alloc&& __a)
1384    -> decltype(__a.select_on_container_copy_construction(), true_type());
1385
1386template <class _Alloc>
1387auto
1388__has_select_on_container_copy_construction_test(const volatile _Alloc& __a)
1389    -> false_type;
1390
1391template <class _Alloc>
1392struct __has_select_on_container_copy_construction
1393    : integral_constant<bool,
1394        is_same<
1395            decltype(__has_select_on_container_copy_construction_test(declval<_Alloc&>())),
1396            true_type>::value>
1397{
1398};
1399
1400#else  // _LIBCPP_HAS_NO_ADVANCED_SFINAE
1401
1402#ifndef _LIBCPP_HAS_NO_VARIADICS
1403
1404template <class _Alloc, class _Pointer, class ..._Args>
1405struct __has_construct
1406    : false_type
1407{
1408};
1409
1410#else  // _LIBCPP_HAS_NO_VARIADICS
1411
1412template <class _Alloc, class _Pointer, class _Args>
1413struct __has_construct
1414    : false_type
1415{
1416};
1417
1418#endif  // _LIBCPP_HAS_NO_VARIADICS
1419
1420template <class _Alloc, class _Pointer>
1421struct __has_destroy
1422    : false_type
1423{
1424};
1425
1426template <class _Alloc>
1427struct __has_max_size
1428    : true_type
1429{
1430};
1431
1432template <class _Alloc>
1433struct __has_select_on_container_copy_construction
1434    : false_type
1435{
1436};
1437
1438#endif  // _LIBCPP_HAS_NO_ADVANCED_SFINAE
1439
1440template <class _Alloc, class _Ptr, bool = __has_difference_type<_Alloc>::value>
1441struct __alloc_traits_difference_type
1442{
1443    typedef typename pointer_traits<_Ptr>::difference_type type;
1444};
1445
1446template <class _Alloc, class _Ptr>
1447struct __alloc_traits_difference_type<_Alloc, _Ptr, true>
1448{
1449    typedef typename _Alloc::difference_type type;
1450};
1451
1452template <class _Alloc>
1453struct _LIBCPP_TYPE_VIS_ONLY allocator_traits
1454{
1455    typedef _Alloc                              allocator_type;
1456    typedef typename allocator_type::value_type value_type;
1457
1458    typedef typename __pointer_type<value_type, allocator_type>::type pointer;
1459    typedef typename __const_pointer<value_type, pointer, allocator_type>::type const_pointer;
1460    typedef typename __void_pointer<pointer, allocator_type>::type void_pointer;
1461    typedef typename __const_void_pointer<pointer, allocator_type>::type const_void_pointer;
1462
1463    typedef typename __alloc_traits_difference_type<allocator_type, pointer>::type difference_type;
1464    typedef typename __size_type<allocator_type, difference_type>::type size_type;
1465
1466    typedef typename __propagate_on_container_copy_assignment<allocator_type>::type
1467                     propagate_on_container_copy_assignment;
1468    typedef typename __propagate_on_container_move_assignment<allocator_type>::type
1469                     propagate_on_container_move_assignment;
1470    typedef typename __propagate_on_container_swap<allocator_type>::type
1471                     propagate_on_container_swap;
1472    typedef typename __is_always_equal<allocator_type>::type
1473                     is_always_equal;
1474
1475#ifndef _LIBCPP_HAS_NO_TEMPLATE_ALIASES
1476    template <class _Tp> using rebind_alloc =
1477                  typename __allocator_traits_rebind<allocator_type, _Tp>::type;
1478    template <class _Tp> using rebind_traits = allocator_traits<rebind_alloc<_Tp>>;
1479#else  // _LIBCPP_HAS_NO_TEMPLATE_ALIASES
1480    template <class _Tp> struct rebind_alloc
1481        {typedef typename __allocator_traits_rebind<allocator_type, _Tp>::type other;};
1482    template <class _Tp> struct rebind_traits
1483        {typedef allocator_traits<typename rebind_alloc<_Tp>::other> other;};
1484#endif  // _LIBCPP_HAS_NO_TEMPLATE_ALIASES
1485
1486    _LIBCPP_INLINE_VISIBILITY
1487    static pointer allocate(allocator_type& __a, size_type __n)
1488        {return __a.allocate(__n);}
1489    _LIBCPP_INLINE_VISIBILITY
1490    static pointer allocate(allocator_type& __a, size_type __n, const_void_pointer __hint)
1491        {return allocate(__a, __n, __hint,
1492            __has_allocate_hint<allocator_type, size_type, const_void_pointer>());}
1493
1494    _LIBCPP_INLINE_VISIBILITY
1495    static void deallocate(allocator_type& __a, pointer __p, size_type __n) _NOEXCEPT
1496        {__a.deallocate(__p, __n);}
1497
1498#ifndef _LIBCPP_HAS_NO_VARIADICS
1499    template <class _Tp, class... _Args>
1500        _LIBCPP_INLINE_VISIBILITY
1501        static void construct(allocator_type& __a, _Tp* __p, _Args&&... __args)
1502            {__construct(__has_construct<allocator_type, _Tp*, _Args...>(),
1503                         __a, __p, _VSTD::forward<_Args>(__args)...);}
1504#else  // _LIBCPP_HAS_NO_VARIADICS
1505    template <class _Tp>
1506        _LIBCPP_INLINE_VISIBILITY
1507        static void construct(allocator_type& __a, _Tp* __p)
1508            {
1509                ::new ((void*)__p) _Tp();
1510            }
1511    template <class _Tp, class _A0>
1512        _LIBCPP_INLINE_VISIBILITY
1513        static void construct(allocator_type& __a, _Tp* __p, const _A0& __a0)
1514            {
1515                ::new ((void*)__p) _Tp(__a0);
1516            }
1517    template <class _Tp, class _A0, class _A1>
1518        _LIBCPP_INLINE_VISIBILITY
1519        static void construct(allocator_type& __a, _Tp* __p, const _A0& __a0,
1520                              const _A1& __a1)
1521            {
1522                ::new ((void*)__p) _Tp(__a0, __a1);
1523            }
1524    template <class _Tp, class _A0, class _A1, class _A2>
1525        _LIBCPP_INLINE_VISIBILITY
1526        static void construct(allocator_type& __a, _Tp* __p, const _A0& __a0,
1527                              const _A1& __a1, const _A2& __a2)
1528            {
1529                ::new ((void*)__p) _Tp(__a0, __a1, __a2);
1530            }
1531#endif  // _LIBCPP_HAS_NO_VARIADICS
1532
1533    template <class _Tp>
1534        _LIBCPP_INLINE_VISIBILITY
1535        static void destroy(allocator_type& __a, _Tp* __p)
1536            {__destroy(__has_destroy<allocator_type, _Tp*>(), __a, __p);}
1537
1538    _LIBCPP_INLINE_VISIBILITY
1539    static size_type max_size(const allocator_type& __a) _NOEXCEPT
1540        {return __max_size(__has_max_size<const allocator_type>(), __a);}
1541
1542    _LIBCPP_INLINE_VISIBILITY
1543    static allocator_type
1544        select_on_container_copy_construction(const allocator_type& __a)
1545            {return select_on_container_copy_construction(
1546                __has_select_on_container_copy_construction<const allocator_type>(),
1547                __a);}
1548
1549    template <class _Ptr>
1550        _LIBCPP_INLINE_VISIBILITY
1551        static
1552        void
1553        __construct_forward(allocator_type& __a, _Ptr __begin1, _Ptr __end1, _Ptr& __begin2)
1554        {
1555            for (; __begin1 != __end1; ++__begin1, ++__begin2)
1556                construct(__a, _VSTD::__to_raw_pointer(__begin2), _VSTD::move_if_noexcept(*__begin1));
1557        }
1558
1559    template <class _Tp>
1560        _LIBCPP_INLINE_VISIBILITY
1561        static
1562        typename enable_if
1563        <
1564            (is_same<allocator_type, allocator<_Tp> >::value
1565                || !__has_construct<allocator_type, _Tp*, _Tp>::value) &&
1566             is_trivially_move_constructible<_Tp>::value,
1567            void
1568        >::type
1569        __construct_forward(allocator_type& __a, _Tp* __begin1, _Tp* __end1, _Tp*& __begin2)
1570        {
1571            ptrdiff_t _Np = __end1 - __begin1;
1572            if (_Np > 0)
1573            {
1574                _VSTD::memcpy(__begin2, __begin1, _Np * sizeof(_Tp));
1575                __begin2 += _Np;
1576            }
1577        }
1578
1579    template <class _Iter, class _Ptr>
1580        _LIBCPP_INLINE_VISIBILITY
1581        static
1582        void
1583        __construct_range_forward(allocator_type& __a, _Iter __begin1, _Iter __end1, _Ptr& __begin2)
1584        {
1585            for (; __begin1 != __end1; ++__begin1, (void) ++__begin2)
1586                construct(__a, _VSTD::__to_raw_pointer(__begin2), *__begin1);
1587        }
1588
1589    template <class _Tp>
1590        _LIBCPP_INLINE_VISIBILITY
1591        static
1592        typename enable_if
1593        <
1594            (is_same<allocator_type, allocator<_Tp> >::value
1595                || !__has_construct<allocator_type, _Tp*, _Tp>::value) &&
1596             is_trivially_move_constructible<_Tp>::value,
1597            void
1598        >::type
1599        __construct_range_forward(allocator_type& __a, _Tp* __begin1, _Tp* __end1, _Tp*& __begin2)
1600        {
1601            typedef typename remove_const<_Tp>::type _Vp;
1602            ptrdiff_t _Np = __end1 - __begin1;
1603            if (_Np > 0)
1604            {
1605                _VSTD::memcpy(const_cast<_Vp*>(__begin2), __begin1, _Np * sizeof(_Tp));
1606                __begin2 += _Np;
1607            }
1608        }
1609
1610    template <class _Ptr>
1611        _LIBCPP_INLINE_VISIBILITY
1612        static
1613        void
1614        __construct_backward(allocator_type& __a, _Ptr __begin1, _Ptr __end1, _Ptr& __end2)
1615        {
1616            while (__end1 != __begin1)
1617            {
1618                construct(__a, _VSTD::__to_raw_pointer(__end2-1), _VSTD::move_if_noexcept(*--__end1));
1619                --__end2;
1620            }
1621        }
1622
1623    template <class _Tp>
1624        _LIBCPP_INLINE_VISIBILITY
1625        static
1626        typename enable_if
1627        <
1628            (is_same<allocator_type, allocator<_Tp> >::value
1629                || !__has_construct<allocator_type, _Tp*, _Tp>::value) &&
1630             is_trivially_move_constructible<_Tp>::value,
1631            void
1632        >::type
1633        __construct_backward(allocator_type& __a, _Tp* __begin1, _Tp* __end1, _Tp*& __end2)
1634        {
1635            ptrdiff_t _Np = __end1 - __begin1;
1636            __end2 -= _Np;
1637            if (_Np > 0)
1638                _VSTD::memcpy(__end2, __begin1, _Np * sizeof(_Tp));
1639        }
1640
1641private:
1642
1643    _LIBCPP_INLINE_VISIBILITY
1644    static pointer allocate(allocator_type& __a, size_type __n,
1645        const_void_pointer __hint, true_type)
1646        {return __a.allocate(__n, __hint);}
1647    _LIBCPP_INLINE_VISIBILITY
1648    static pointer allocate(allocator_type& __a, size_type __n,
1649        const_void_pointer, false_type)
1650        {return __a.allocate(__n);}
1651
1652#ifndef _LIBCPP_HAS_NO_VARIADICS
1653    template <class _Tp, class... _Args>
1654        _LIBCPP_INLINE_VISIBILITY
1655        static void __construct(true_type, allocator_type& __a, _Tp* __p, _Args&&... __args)
1656            {__a.construct(__p, _VSTD::forward<_Args>(__args)...);}
1657    template <class _Tp, class... _Args>
1658        _LIBCPP_INLINE_VISIBILITY
1659        static void __construct(false_type, allocator_type&, _Tp* __p, _Args&&... __args)
1660            {
1661                ::new ((void*)__p) _Tp(_VSTD::forward<_Args>(__args)...);
1662            }
1663#endif  // _LIBCPP_HAS_NO_VARIADICS
1664
1665    template <class _Tp>
1666        _LIBCPP_INLINE_VISIBILITY
1667        static void __destroy(true_type, allocator_type& __a, _Tp* __p)
1668            {__a.destroy(__p);}
1669    template <class _Tp>
1670        _LIBCPP_INLINE_VISIBILITY
1671        static void __destroy(false_type, allocator_type&, _Tp* __p)
1672            {
1673                __p->~_Tp();
1674            }
1675
1676    _LIBCPP_INLINE_VISIBILITY
1677    static size_type __max_size(true_type, const allocator_type& __a)
1678            {return __a.max_size();}
1679    _LIBCPP_INLINE_VISIBILITY
1680    static size_type __max_size(false_type, const allocator_type&)
1681            {return numeric_limits<size_type>::max() / sizeof(value_type);}
1682
1683    _LIBCPP_INLINE_VISIBILITY
1684    static allocator_type
1685        select_on_container_copy_construction(true_type, const allocator_type& __a)
1686            {return __a.select_on_container_copy_construction();}
1687    _LIBCPP_INLINE_VISIBILITY
1688    static allocator_type
1689        select_on_container_copy_construction(false_type, const allocator_type& __a)
1690            {return __a;}
1691};
1692
1693template <class _Traits, class _Tp>
1694struct __rebind_alloc_helper
1695{
1696#ifndef _LIBCPP_HAS_NO_TEMPLATE_ALIASES
1697    typedef typename _Traits::template rebind_alloc<_Tp>        type;
1698#else
1699    typedef typename _Traits::template rebind_alloc<_Tp>::other type;
1700#endif
1701};
1702
1703// allocator
1704
1705template <class _Tp>
1706class _LIBCPP_TYPE_VIS_ONLY allocator
1707{
1708public:
1709    typedef size_t            size_type;
1710    typedef ptrdiff_t         difference_type;
1711    typedef _Tp*              pointer;
1712    typedef const _Tp*        const_pointer;
1713    typedef _Tp&              reference;
1714    typedef const _Tp&        const_reference;
1715    typedef _Tp               value_type;
1716
1717    typedef true_type propagate_on_container_move_assignment;
1718    typedef true_type is_always_equal;
1719
1720    template <class _Up> struct rebind {typedef allocator<_Up> other;};
1721
1722    _LIBCPP_INLINE_VISIBILITY allocator() _NOEXCEPT {}
1723    template <class _Up> _LIBCPP_INLINE_VISIBILITY allocator(const allocator<_Up>&) _NOEXCEPT {}
1724    _LIBCPP_INLINE_VISIBILITY pointer address(reference __x) const _NOEXCEPT
1725        {return _VSTD::addressof(__x);}
1726    _LIBCPP_INLINE_VISIBILITY const_pointer address(const_reference __x) const _NOEXCEPT
1727        {return _VSTD::addressof(__x);}
1728    _LIBCPP_INLINE_VISIBILITY pointer allocate(size_type __n, allocator<void>::const_pointer = 0)
1729        {
1730        if (__n > max_size())
1731#ifndef _LIBCPP_NO_EXCEPTIONS
1732            throw bad_alloc();
1733#else
1734            assert(!"allocator<T>::allocate::bad_alloc");
1735#endif
1736        return static_cast<pointer>(_VSTD::__allocate(__n * sizeof(_Tp)));
1737        }
1738    _LIBCPP_INLINE_VISIBILITY void deallocate(pointer __p, size_type) _NOEXCEPT
1739        {_VSTD::__deallocate((void*)__p);}
1740    _LIBCPP_INLINE_VISIBILITY size_type max_size() const _NOEXCEPT
1741        {return size_type(~0) / sizeof(_Tp);}
1742#if !defined(_LIBCPP_HAS_NO_RVALUE_REFERENCES) && !defined(_LIBCPP_HAS_NO_VARIADICS)
1743    template <class _Up, class... _Args>
1744        _LIBCPP_INLINE_VISIBILITY
1745        void
1746        construct(_Up* __p, _Args&&... __args)
1747        {
1748            ::new((void*)__p) _Up(_VSTD::forward<_Args>(__args)...);
1749        }
1750#else  // !defined(_LIBCPP_HAS_NO_RVALUE_REFERENCES) && !defined(_LIBCPP_HAS_NO_VARIADICS)
1751        _LIBCPP_INLINE_VISIBILITY
1752        void
1753        construct(pointer __p)
1754        {
1755            ::new((void*)__p) _Tp();
1756        }
1757# if defined(_LIBCPP_HAS_NO_RVALUE_REFERENCES)
1758
1759    template <class _A0>
1760        _LIBCPP_INLINE_VISIBILITY
1761        void
1762        construct(pointer __p, _A0& __a0)
1763        {
1764            ::new((void*)__p) _Tp(__a0);
1765        }
1766    template <class _A0>
1767        _LIBCPP_INLINE_VISIBILITY
1768        void
1769        construct(pointer __p, const _A0& __a0)
1770        {
1771            ::new((void*)__p) _Tp(__a0);
1772        }
1773# endif  // defined(_LIBCPP_HAS_NO_RVALUE_REFERENCES)
1774    template <class _A0, class _A1>
1775        _LIBCPP_INLINE_VISIBILITY
1776        void
1777        construct(pointer __p, _A0& __a0, _A1& __a1)
1778        {
1779            ::new((void*)__p) _Tp(__a0, __a1);
1780        }
1781    template <class _A0, class _A1>
1782        _LIBCPP_INLINE_VISIBILITY
1783        void
1784        construct(pointer __p, const _A0& __a0, _A1& __a1)
1785        {
1786            ::new((void*)__p) _Tp(__a0, __a1);
1787        }
1788    template <class _A0, class _A1>
1789        _LIBCPP_INLINE_VISIBILITY
1790        void
1791        construct(pointer __p, _A0& __a0, const _A1& __a1)
1792        {
1793            ::new((void*)__p) _Tp(__a0, __a1);
1794        }
1795    template <class _A0, class _A1>
1796        _LIBCPP_INLINE_VISIBILITY
1797        void
1798        construct(pointer __p, const _A0& __a0, const _A1& __a1)
1799        {
1800            ::new((void*)__p) _Tp(__a0, __a1);
1801        }
1802#endif  // !defined(_LIBCPP_HAS_NO_RVALUE_REFERENCES) && !defined(_LIBCPP_HAS_NO_VARIADICS)
1803    _LIBCPP_INLINE_VISIBILITY void destroy(pointer __p) {__p->~_Tp();}
1804};
1805
1806template <class _Tp>
1807class _LIBCPP_TYPE_VIS_ONLY allocator<const _Tp>
1808{
1809public:
1810    typedef size_t            size_type;
1811    typedef ptrdiff_t         difference_type;
1812    typedef const _Tp*        pointer;
1813    typedef const _Tp*        const_pointer;
1814    typedef const _Tp&        reference;
1815    typedef const _Tp&        const_reference;
1816    typedef const _Tp         value_type;
1817
1818    typedef true_type propagate_on_container_move_assignment;
1819    typedef true_type is_always_equal;
1820
1821    template <class _Up> struct rebind {typedef allocator<_Up> other;};
1822
1823    _LIBCPP_INLINE_VISIBILITY allocator() _NOEXCEPT {}
1824    template <class _Up> _LIBCPP_INLINE_VISIBILITY allocator(const allocator<_Up>&) _NOEXCEPT {}
1825    _LIBCPP_INLINE_VISIBILITY const_pointer address(const_reference __x) const _NOEXCEPT
1826        {return _VSTD::addressof(__x);}
1827    _LIBCPP_INLINE_VISIBILITY pointer allocate(size_type __n, allocator<void>::const_pointer = 0)
1828    {
1829        if (__n > max_size())
1830#ifndef _LIBCPP_NO_EXCEPTIONS
1831            throw bad_alloc();
1832#else
1833            assert(!"allocator<const T>::allocate::bad_alloc");
1834#endif
1835        return static_cast<pointer>(_VSTD::__allocate(__n * sizeof(_Tp)));
1836        }
1837    _LIBCPP_INLINE_VISIBILITY void deallocate(pointer __p, size_type) _NOEXCEPT
1838        {_VSTD::__deallocate((void*)__p);}
1839    _LIBCPP_INLINE_VISIBILITY size_type max_size() const _NOEXCEPT
1840        {return size_type(~0) / sizeof(_Tp);}
1841#if !defined(_LIBCPP_HAS_NO_RVALUE_REFERENCES) && !defined(_LIBCPP_HAS_NO_VARIADICS)
1842    template <class _Up, class... _Args>
1843        _LIBCPP_INLINE_VISIBILITY
1844        void
1845        construct(_Up* __p, _Args&&... __args)
1846        {
1847            ::new((void*)__p) _Up(_VSTD::forward<_Args>(__args)...);
1848        }
1849#else  // !defined(_LIBCPP_HAS_NO_RVALUE_REFERENCES) && !defined(_LIBCPP_HAS_NO_VARIADICS)
1850        _LIBCPP_INLINE_VISIBILITY
1851        void
1852        construct(pointer __p)
1853        {
1854            ::new((void*)__p) _Tp();
1855        }
1856# if defined(_LIBCPP_HAS_NO_RVALUE_REFERENCES)
1857
1858    template <class _A0>
1859        _LIBCPP_INLINE_VISIBILITY
1860        void
1861        construct(pointer __p, _A0& __a0)
1862        {
1863            ::new((void*)__p) _Tp(__a0);
1864        }
1865    template <class _A0>
1866        _LIBCPP_INLINE_VISIBILITY
1867        void
1868        construct(pointer __p, const _A0& __a0)
1869        {
1870            ::new((void*)__p) _Tp(__a0);
1871        }
1872# endif  // defined(_LIBCPP_HAS_NO_RVALUE_REFERENCES)
1873    template <class _A0, class _A1>
1874        _LIBCPP_INLINE_VISIBILITY
1875        void
1876        construct(pointer __p, _A0& __a0, _A1& __a1)
1877        {
1878            ::new((void*)__p) _Tp(__a0, __a1);
1879        }
1880    template <class _A0, class _A1>
1881        _LIBCPP_INLINE_VISIBILITY
1882        void
1883        construct(pointer __p, const _A0& __a0, _A1& __a1)
1884        {
1885            ::new((void*)__p) _Tp(__a0, __a1);
1886        }
1887    template <class _A0, class _A1>
1888        _LIBCPP_INLINE_VISIBILITY
1889        void
1890        construct(pointer __p, _A0& __a0, const _A1& __a1)
1891        {
1892            ::new((void*)__p) _Tp(__a0, __a1);
1893        }
1894    template <class _A0, class _A1>
1895        _LIBCPP_INLINE_VISIBILITY
1896        void
1897        construct(pointer __p, const _A0& __a0, const _A1& __a1)
1898        {
1899            ::new((void*)__p) _Tp(__a0, __a1);
1900        }
1901#endif  // !defined(_LIBCPP_HAS_NO_RVALUE_REFERENCES) && !defined(_LIBCPP_HAS_NO_VARIADICS)
1902    _LIBCPP_INLINE_VISIBILITY void destroy(pointer __p) {__p->~_Tp();}
1903};
1904
1905template <class _Tp, class _Up>
1906inline _LIBCPP_INLINE_VISIBILITY
1907bool operator==(const allocator<_Tp>&, const allocator<_Up>&) _NOEXCEPT {return true;}
1908
1909template <class _Tp, class _Up>
1910inline _LIBCPP_INLINE_VISIBILITY
1911bool operator!=(const allocator<_Tp>&, const allocator<_Up>&) _NOEXCEPT {return false;}
1912
1913template <class _OutputIterator, class _Tp>
1914class _LIBCPP_TYPE_VIS_ONLY raw_storage_iterator
1915    : public iterator<output_iterator_tag,
1916                      _Tp,                                         // purposefully not C++03
1917                      ptrdiff_t,                                   // purposefully not C++03
1918                      _Tp*,                                        // purposefully not C++03
1919                      raw_storage_iterator<_OutputIterator, _Tp>&> // purposefully not C++03
1920{
1921private:
1922    _OutputIterator __x_;
1923public:
1924    _LIBCPP_INLINE_VISIBILITY explicit raw_storage_iterator(_OutputIterator __x) : __x_(__x) {}
1925    _LIBCPP_INLINE_VISIBILITY raw_storage_iterator& operator*() {return *this;}
1926    _LIBCPP_INLINE_VISIBILITY raw_storage_iterator& operator=(const _Tp& __element)
1927        {::new(&*__x_) _Tp(__element); return *this;}
1928#if _LIBCPP_STD_VER >= 14
1929    _LIBCPP_INLINE_VISIBILITY raw_storage_iterator& operator=(_Tp&& __element)
1930        {::new(&*__x_) _Tp(_VSTD::move(__element)); return *this;}
1931#endif
1932    _LIBCPP_INLINE_VISIBILITY raw_storage_iterator& operator++() {++__x_; return *this;}
1933    _LIBCPP_INLINE_VISIBILITY raw_storage_iterator  operator++(int)
1934        {raw_storage_iterator __t(*this); ++__x_; return __t;}
1935#if _LIBCPP_STD_VER >= 14
1936    _LIBCPP_INLINE_VISIBILITY _OutputIterator base() const { return __x_; }
1937#endif
1938};
1939
1940template <class _Tp>
1941pair<_Tp*, ptrdiff_t>
1942get_temporary_buffer(ptrdiff_t __n) _NOEXCEPT
1943{
1944    pair<_Tp*, ptrdiff_t> __r(0, 0);
1945    const ptrdiff_t __m = (~ptrdiff_t(0) ^
1946                           ptrdiff_t(ptrdiff_t(1) << (sizeof(ptrdiff_t) * __CHAR_BIT__ - 1)))
1947                           / sizeof(_Tp);
1948    if (__n > __m)
1949        __n = __m;
1950    while (__n > 0)
1951    {
1952        __r.first = static_cast<_Tp*>(::operator new(__n * sizeof(_Tp), nothrow));
1953        if (__r.first)
1954        {
1955            __r.second = __n;
1956            break;
1957        }
1958        __n /= 2;
1959    }
1960    return __r;
1961}
1962
1963template <class _Tp>
1964inline _LIBCPP_INLINE_VISIBILITY
1965void return_temporary_buffer(_Tp* __p) _NOEXCEPT {::operator delete(__p);}
1966
1967template <class _Tp>
1968struct auto_ptr_ref
1969{
1970    _Tp* __ptr_;
1971};
1972
1973template<class _Tp>
1974class _LIBCPP_TYPE_VIS_ONLY auto_ptr
1975{
1976private:
1977    _Tp* __ptr_;
1978public:
1979    typedef _Tp element_type;
1980
1981    _LIBCPP_INLINE_VISIBILITY explicit auto_ptr(_Tp* __p = 0) throw() : __ptr_(__p) {}
1982    _LIBCPP_INLINE_VISIBILITY auto_ptr(auto_ptr& __p) throw() : __ptr_(__p.release()) {}
1983    template<class _Up> _LIBCPP_INLINE_VISIBILITY auto_ptr(auto_ptr<_Up>& __p) throw()
1984        : __ptr_(__p.release()) {}
1985    _LIBCPP_INLINE_VISIBILITY auto_ptr& operator=(auto_ptr& __p) throw()
1986        {reset(__p.release()); return *this;}
1987    template<class _Up> _LIBCPP_INLINE_VISIBILITY auto_ptr& operator=(auto_ptr<_Up>& __p) throw()
1988        {reset(__p.release()); return *this;}
1989    _LIBCPP_INLINE_VISIBILITY auto_ptr& operator=(auto_ptr_ref<_Tp> __p) throw()
1990        {reset(__p.__ptr_); return *this;}
1991    _LIBCPP_INLINE_VISIBILITY ~auto_ptr() throw() {delete __ptr_;}
1992
1993    _LIBCPP_INLINE_VISIBILITY _Tp& operator*() const throw()
1994        {return *__ptr_;}
1995    _LIBCPP_INLINE_VISIBILITY _Tp* operator->() const throw() {return __ptr_;}
1996    _LIBCPP_INLINE_VISIBILITY _Tp* get() const throw() {return __ptr_;}
1997    _LIBCPP_INLINE_VISIBILITY _Tp* release() throw()
1998    {
1999        _Tp* __t = __ptr_;
2000        __ptr_ = 0;
2001        return __t;
2002    }
2003    _LIBCPP_INLINE_VISIBILITY void reset(_Tp* __p = 0) throw()
2004    {
2005        if (__ptr_ != __p)
2006            delete __ptr_;
2007        __ptr_ = __p;
2008    }
2009
2010    _LIBCPP_INLINE_VISIBILITY auto_ptr(auto_ptr_ref<_Tp> __p) throw() : __ptr_(__p.__ptr_) {}
2011    template<class _Up> _LIBCPP_INLINE_VISIBILITY operator auto_ptr_ref<_Up>() throw()
2012        {auto_ptr_ref<_Up> __t; __t.__ptr_ = release(); return __t;}
2013    template<class _Up> _LIBCPP_INLINE_VISIBILITY operator auto_ptr<_Up>() throw()
2014        {return auto_ptr<_Up>(release());}
2015};
2016
2017template <>
2018class _LIBCPP_TYPE_VIS_ONLY auto_ptr<void>
2019{
2020public:
2021    typedef void element_type;
2022};
2023
2024template <class _T1, class _T2, bool = is_same<typename remove_cv<_T1>::type,
2025                                                     typename remove_cv<_T2>::type>::value,
2026                                bool = is_empty<_T1>::value
2027                                       && !__libcpp_is_final<_T1>::value,
2028                                bool = is_empty<_T2>::value
2029                                       && !__libcpp_is_final<_T2>::value
2030         >
2031struct __libcpp_compressed_pair_switch;
2032
2033template <class _T1, class _T2, bool IsSame>
2034struct __libcpp_compressed_pair_switch<_T1, _T2, IsSame, false, false> {enum {value = 0};};
2035
2036template <class _T1, class _T2, bool IsSame>
2037struct __libcpp_compressed_pair_switch<_T1, _T2, IsSame, true, false>  {enum {value = 1};};
2038
2039template <class _T1, class _T2, bool IsSame>
2040struct __libcpp_compressed_pair_switch<_T1, _T2, IsSame, false, true>  {enum {value = 2};};
2041
2042template <class _T1, class _T2>
2043struct __libcpp_compressed_pair_switch<_T1, _T2, false, true, true>    {enum {value = 3};};
2044
2045template <class _T1, class _T2>
2046struct __libcpp_compressed_pair_switch<_T1, _T2, true, true, true>     {enum {value = 1};};
2047
2048template <class _T1, class _T2, unsigned = __libcpp_compressed_pair_switch<_T1, _T2>::value>
2049class __libcpp_compressed_pair_imp;
2050
2051template <class _T1, class _T2>
2052class __libcpp_compressed_pair_imp<_T1, _T2, 0>
2053{
2054private:
2055    _T1 __first_;
2056    _T2 __second_;
2057public:
2058    typedef _T1 _T1_param;
2059    typedef _T2 _T2_param;
2060
2061    typedef typename remove_reference<_T1>::type& _T1_reference;
2062    typedef typename remove_reference<_T2>::type& _T2_reference;
2063
2064    typedef const typename remove_reference<_T1>::type& _T1_const_reference;
2065    typedef const typename remove_reference<_T2>::type& _T2_const_reference;
2066
2067    _LIBCPP_INLINE_VISIBILITY __libcpp_compressed_pair_imp() : __first_(), __second_() {}
2068    _LIBCPP_INLINE_VISIBILITY explicit __libcpp_compressed_pair_imp(_T1_param __t1)
2069        : __first_(_VSTD::forward<_T1_param>(__t1)), __second_() {}
2070    _LIBCPP_INLINE_VISIBILITY explicit __libcpp_compressed_pair_imp(_T2_param __t2)
2071        : __first_(), __second_(_VSTD::forward<_T2_param>(__t2)) {}
2072    _LIBCPP_INLINE_VISIBILITY __libcpp_compressed_pair_imp(_T1_param __t1, _T2_param __t2)
2073        : __first_(_VSTD::forward<_T1_param>(__t1)), __second_(_VSTD::forward<_T2_param>(__t2)) {}
2074
2075#if defined(_LIBCPP_HAS_NO_DEFAULTED_FUNCTIONS) && !defined(_LIBCPP_HAS_NO_RVALUE_REFERENCES)
2076
2077    _LIBCPP_INLINE_VISIBILITY
2078    __libcpp_compressed_pair_imp(const __libcpp_compressed_pair_imp& __p)
2079        _NOEXCEPT_(is_nothrow_copy_constructible<_T1>::value &&
2080                   is_nothrow_copy_constructible<_T2>::value)
2081        : __first_(__p.first()),
2082          __second_(__p.second()) {}
2083
2084    _LIBCPP_INLINE_VISIBILITY
2085    __libcpp_compressed_pair_imp& operator=(const __libcpp_compressed_pair_imp& __p)
2086        _NOEXCEPT_(is_nothrow_copy_assignable<_T1>::value &&
2087                   is_nothrow_copy_assignable<_T2>::value)
2088        {
2089            __first_ = __p.first();
2090            __second_ = __p.second();
2091            return *this;
2092        }
2093
2094    _LIBCPP_INLINE_VISIBILITY
2095    __libcpp_compressed_pair_imp(__libcpp_compressed_pair_imp&& __p)
2096        _NOEXCEPT_(is_nothrow_move_constructible<_T1>::value &&
2097                   is_nothrow_move_constructible<_T2>::value)
2098        : __first_(_VSTD::forward<_T1>(__p.first())),
2099          __second_(_VSTD::forward<_T2>(__p.second())) {}
2100
2101    _LIBCPP_INLINE_VISIBILITY
2102    __libcpp_compressed_pair_imp& operator=(__libcpp_compressed_pair_imp&& __p)
2103        _NOEXCEPT_(is_nothrow_move_assignable<_T1>::value &&
2104                   is_nothrow_move_assignable<_T2>::value)
2105        {
2106            __first_ = _VSTD::forward<_T1>(__p.first());
2107            __second_ = _VSTD::forward<_T2>(__p.second());
2108            return *this;
2109        }
2110
2111#endif  // defined(_LIBCPP_HAS_NO_DEFAULTED_FUNCTIONS) && !defined(_LIBCPP_HAS_NO_RVALUE_REFERENCES)
2112
2113#ifndef _LIBCPP_HAS_NO_VARIADICS
2114
2115    template <class... _Args1, class... _Args2, size_t... _I1, size_t... _I2>
2116        _LIBCPP_INLINE_VISIBILITY
2117        __libcpp_compressed_pair_imp(piecewise_construct_t __pc,
2118                                     tuple<_Args1...> __first_args,
2119                                     tuple<_Args2...> __second_args,
2120                                     __tuple_indices<_I1...>,
2121                                     __tuple_indices<_I2...>)
2122            : __first_(_VSTD::forward<_Args1>(_VSTD::get<_I1>(__first_args))...),
2123              __second_(_VSTD::forward<_Args2>(_VSTD::get<_I2>(__second_args))...)
2124            {}
2125
2126#endif  // _LIBCPP_HAS_NO_VARIADICS
2127
2128    _LIBCPP_INLINE_VISIBILITY _T1_reference       first() _NOEXCEPT       {return __first_;}
2129    _LIBCPP_INLINE_VISIBILITY _T1_const_reference first() const _NOEXCEPT {return __first_;}
2130
2131    _LIBCPP_INLINE_VISIBILITY _T2_reference       second() _NOEXCEPT       {return __second_;}
2132    _LIBCPP_INLINE_VISIBILITY _T2_const_reference second() const _NOEXCEPT {return __second_;}
2133
2134    _LIBCPP_INLINE_VISIBILITY void swap(__libcpp_compressed_pair_imp& __x)
2135        _NOEXCEPT_(__is_nothrow_swappable<_T1>::value &&
2136                   __is_nothrow_swappable<_T2>::value)
2137    {
2138        using _VSTD::swap;
2139        swap(__first_, __x.__first_);
2140        swap(__second_, __x.__second_);
2141    }
2142};
2143
2144template <class _T1, class _T2>
2145class __libcpp_compressed_pair_imp<_T1, _T2, 1>
2146    : private _T1
2147{
2148private:
2149    _T2 __second_;
2150public:
2151    typedef _T1 _T1_param;
2152    typedef _T2 _T2_param;
2153
2154    typedef _T1&                                        _T1_reference;
2155    typedef typename remove_reference<_T2>::type& _T2_reference;
2156
2157    typedef const _T1&                                        _T1_const_reference;
2158    typedef const typename remove_reference<_T2>::type& _T2_const_reference;
2159
2160    _LIBCPP_INLINE_VISIBILITY __libcpp_compressed_pair_imp() : __second_() {}
2161    _LIBCPP_INLINE_VISIBILITY explicit __libcpp_compressed_pair_imp(_T1_param __t1)
2162        : _T1(_VSTD::forward<_T1_param>(__t1)), __second_() {}
2163    _LIBCPP_INLINE_VISIBILITY explicit __libcpp_compressed_pair_imp(_T2_param __t2)
2164        : __second_(_VSTD::forward<_T2_param>(__t2)) {}
2165    _LIBCPP_INLINE_VISIBILITY __libcpp_compressed_pair_imp(_T1_param __t1, _T2_param __t2)
2166        : _T1(_VSTD::forward<_T1_param>(__t1)), __second_(_VSTD::forward<_T2_param>(__t2)) {}
2167
2168#if defined(_LIBCPP_HAS_NO_DEFAULTED_FUNCTIONS) && !defined(_LIBCPP_HAS_NO_RVALUE_REFERENCES)
2169
2170    _LIBCPP_INLINE_VISIBILITY
2171    __libcpp_compressed_pair_imp(const __libcpp_compressed_pair_imp& __p)
2172        _NOEXCEPT_(is_nothrow_copy_constructible<_T1>::value &&
2173                   is_nothrow_copy_constructible<_T2>::value)
2174        : _T1(__p.first()), __second_(__p.second()) {}
2175
2176    _LIBCPP_INLINE_VISIBILITY
2177    __libcpp_compressed_pair_imp& operator=(const __libcpp_compressed_pair_imp& __p)
2178        _NOEXCEPT_(is_nothrow_copy_assignable<_T1>::value &&
2179                   is_nothrow_copy_assignable<_T2>::value)
2180        {
2181            _T1::operator=(__p.first());
2182            __second_ = __p.second();
2183            return *this;
2184        }
2185
2186    _LIBCPP_INLINE_VISIBILITY
2187    __libcpp_compressed_pair_imp(__libcpp_compressed_pair_imp&& __p)
2188        _NOEXCEPT_(is_nothrow_move_constructible<_T1>::value &&
2189                   is_nothrow_move_constructible<_T2>::value)
2190        : _T1(_VSTD::move(__p.first())), __second_(_VSTD::forward<_T2>(__p.second())) {}
2191
2192    _LIBCPP_INLINE_VISIBILITY
2193    __libcpp_compressed_pair_imp& operator=(__libcpp_compressed_pair_imp&& __p)
2194        _NOEXCEPT_(is_nothrow_move_assignable<_T1>::value &&
2195                   is_nothrow_move_assignable<_T2>::value)
2196        {
2197            _T1::operator=(_VSTD::move(__p.first()));
2198            __second_ = _VSTD::forward<_T2>(__p.second());
2199            return *this;
2200        }
2201
2202#endif  // defined(_LIBCPP_HAS_NO_DEFAULTED_FUNCTIONS) && !defined(_LIBCPP_HAS_NO_RVALUE_REFERENCES)
2203
2204#ifndef _LIBCPP_HAS_NO_VARIADICS
2205
2206    template <class... _Args1, class... _Args2, size_t... _I1, size_t... _I2>
2207        _LIBCPP_INLINE_VISIBILITY
2208        __libcpp_compressed_pair_imp(piecewise_construct_t __pc,
2209                                     tuple<_Args1...> __first_args,
2210                                     tuple<_Args2...> __second_args,
2211                                     __tuple_indices<_I1...>,
2212                                     __tuple_indices<_I2...>)
2213            : _T1(_VSTD::forward<_Args1>(_VSTD::get<_I1>(__first_args))...),
2214              __second_(_VSTD::forward<_Args2>(_VSTD::get<_I2>(__second_args))...)
2215            {}
2216
2217#endif  // _LIBCPP_HAS_NO_VARIADICS
2218
2219    _LIBCPP_INLINE_VISIBILITY _T1_reference       first() _NOEXCEPT       {return *this;}
2220    _LIBCPP_INLINE_VISIBILITY _T1_const_reference first() const _NOEXCEPT {return *this;}
2221
2222    _LIBCPP_INLINE_VISIBILITY _T2_reference       second() _NOEXCEPT       {return __second_;}
2223    _LIBCPP_INLINE_VISIBILITY _T2_const_reference second() const _NOEXCEPT {return __second_;}
2224
2225    _LIBCPP_INLINE_VISIBILITY void swap(__libcpp_compressed_pair_imp& __x)
2226        _NOEXCEPT_(__is_nothrow_swappable<_T1>::value &&
2227                   __is_nothrow_swappable<_T2>::value)
2228    {
2229        using _VSTD::swap;
2230        swap(__second_, __x.__second_);
2231    }
2232};
2233
2234template <class _T1, class _T2>
2235class __libcpp_compressed_pair_imp<_T1, _T2, 2>
2236    : private _T2
2237{
2238private:
2239    _T1 __first_;
2240public:
2241    typedef _T1 _T1_param;
2242    typedef _T2 _T2_param;
2243
2244    typedef typename remove_reference<_T1>::type& _T1_reference;
2245    typedef _T2&                                        _T2_reference;
2246
2247    typedef const typename remove_reference<_T1>::type& _T1_const_reference;
2248    typedef const _T2&                                        _T2_const_reference;
2249
2250    _LIBCPP_INLINE_VISIBILITY __libcpp_compressed_pair_imp() : __first_() {}
2251    _LIBCPP_INLINE_VISIBILITY explicit __libcpp_compressed_pair_imp(_T1_param __t1)
2252        : __first_(_VSTD::forward<_T1_param>(__t1)) {}
2253    _LIBCPP_INLINE_VISIBILITY explicit __libcpp_compressed_pair_imp(_T2_param __t2)
2254        : _T2(_VSTD::forward<_T2_param>(__t2)), __first_() {}
2255    _LIBCPP_INLINE_VISIBILITY __libcpp_compressed_pair_imp(_T1_param __t1, _T2_param __t2)
2256        _NOEXCEPT_(is_nothrow_move_constructible<_T1>::value &&
2257                   is_nothrow_move_constructible<_T2>::value)
2258        : _T2(_VSTD::forward<_T2_param>(__t2)), __first_(_VSTD::forward<_T1_param>(__t1)) {}
2259
2260#if defined(_LIBCPP_HAS_NO_DEFAULTED_FUNCTIONS) && !defined(_LIBCPP_HAS_NO_RVALUE_REFERENCES)
2261
2262    _LIBCPP_INLINE_VISIBILITY
2263    __libcpp_compressed_pair_imp(const __libcpp_compressed_pair_imp& __p)
2264        _NOEXCEPT_(is_nothrow_copy_constructible<_T1>::value &&
2265                   is_nothrow_copy_constructible<_T2>::value)
2266        : _T2(__p.second()), __first_(__p.first()) {}
2267
2268    _LIBCPP_INLINE_VISIBILITY
2269    __libcpp_compressed_pair_imp& operator=(const __libcpp_compressed_pair_imp& __p)
2270        _NOEXCEPT_(is_nothrow_copy_assignable<_T1>::value &&
2271                   is_nothrow_copy_assignable<_T2>::value)
2272        {
2273            _T2::operator=(__p.second());
2274            __first_ = __p.first();
2275            return *this;
2276        }
2277
2278    _LIBCPP_INLINE_VISIBILITY
2279    __libcpp_compressed_pair_imp(__libcpp_compressed_pair_imp&& __p)
2280        _NOEXCEPT_(is_nothrow_move_constructible<_T1>::value &&
2281                   is_nothrow_move_constructible<_T2>::value)
2282        : _T2(_VSTD::forward<_T2>(__p.second())), __first_(_VSTD::move(__p.first())) {}
2283
2284    _LIBCPP_INLINE_VISIBILITY
2285    __libcpp_compressed_pair_imp& operator=(__libcpp_compressed_pair_imp&& __p)
2286        _NOEXCEPT_(is_nothrow_move_assignable<_T1>::value &&
2287                   is_nothrow_move_assignable<_T2>::value)
2288        {
2289            _T2::operator=(_VSTD::forward<_T2>(__p.second()));
2290            __first_ = _VSTD::move(__p.first());
2291            return *this;
2292        }
2293
2294#endif  // defined(_LIBCPP_HAS_NO_DEFAULTED_FUNCTIONS) && !defined(_LIBCPP_HAS_NO_RVALUE_REFERENCES)
2295
2296#ifndef _LIBCPP_HAS_NO_VARIADICS
2297
2298    template <class... _Args1, class... _Args2, size_t... _I1, size_t... _I2>
2299        _LIBCPP_INLINE_VISIBILITY
2300        __libcpp_compressed_pair_imp(piecewise_construct_t __pc,
2301                                     tuple<_Args1...> __first_args,
2302                                     tuple<_Args2...> __second_args,
2303                                     __tuple_indices<_I1...>,
2304                                     __tuple_indices<_I2...>)
2305            : _T2(_VSTD::forward<_Args2>(_VSTD::get<_I2>(__second_args))...),
2306              __first_(_VSTD::forward<_Args1>(_VSTD::get<_I1>(__first_args))...)
2307
2308            {}
2309
2310#endif  // _LIBCPP_HAS_NO_VARIADICS
2311
2312    _LIBCPP_INLINE_VISIBILITY _T1_reference       first() _NOEXCEPT       {return __first_;}
2313    _LIBCPP_INLINE_VISIBILITY _T1_const_reference first() const _NOEXCEPT {return __first_;}
2314
2315    _LIBCPP_INLINE_VISIBILITY _T2_reference       second() _NOEXCEPT       {return *this;}
2316    _LIBCPP_INLINE_VISIBILITY _T2_const_reference second() const _NOEXCEPT {return *this;}
2317
2318    _LIBCPP_INLINE_VISIBILITY void swap(__libcpp_compressed_pair_imp& __x)
2319        _NOEXCEPT_(__is_nothrow_swappable<_T1>::value &&
2320                   __is_nothrow_swappable<_T2>::value)
2321    {
2322        using _VSTD::swap;
2323        swap(__first_, __x.__first_);
2324    }
2325};
2326
2327template <class _T1, class _T2>
2328class __libcpp_compressed_pair_imp<_T1, _T2, 3>
2329    : private _T1,
2330      private _T2
2331{
2332public:
2333    typedef _T1 _T1_param;
2334    typedef _T2 _T2_param;
2335
2336    typedef _T1& _T1_reference;
2337    typedef _T2& _T2_reference;
2338
2339    typedef const _T1& _T1_const_reference;
2340    typedef const _T2& _T2_const_reference;
2341
2342    _LIBCPP_INLINE_VISIBILITY __libcpp_compressed_pair_imp() {}
2343    _LIBCPP_INLINE_VISIBILITY explicit __libcpp_compressed_pair_imp(_T1_param __t1)
2344        : _T1(_VSTD::forward<_T1_param>(__t1)) {}
2345    _LIBCPP_INLINE_VISIBILITY explicit __libcpp_compressed_pair_imp(_T2_param __t2)
2346        : _T2(_VSTD::forward<_T2_param>(__t2)) {}
2347    _LIBCPP_INLINE_VISIBILITY __libcpp_compressed_pair_imp(_T1_param __t1, _T2_param __t2)
2348        : _T1(_VSTD::forward<_T1_param>(__t1)), _T2(_VSTD::forward<_T2_param>(__t2)) {}
2349
2350#if defined(_LIBCPP_HAS_NO_DEFAULTED_FUNCTIONS) && !defined(_LIBCPP_HAS_NO_RVALUE_REFERENCES)
2351
2352    _LIBCPP_INLINE_VISIBILITY
2353    __libcpp_compressed_pair_imp(const __libcpp_compressed_pair_imp& __p)
2354        _NOEXCEPT_(is_nothrow_copy_constructible<_T1>::value &&
2355                   is_nothrow_copy_constructible<_T2>::value)
2356        : _T1(__p.first()), _T2(__p.second()) {}
2357
2358    _LIBCPP_INLINE_VISIBILITY
2359    __libcpp_compressed_pair_imp& operator=(const __libcpp_compressed_pair_imp& __p)
2360        _NOEXCEPT_(is_nothrow_copy_assignable<_T1>::value &&
2361                   is_nothrow_copy_assignable<_T2>::value)
2362        {
2363            _T1::operator=(__p.first());
2364            _T2::operator=(__p.second());
2365            return *this;
2366        }
2367
2368    _LIBCPP_INLINE_VISIBILITY
2369    __libcpp_compressed_pair_imp(__libcpp_compressed_pair_imp&& __p)
2370        _NOEXCEPT_(is_nothrow_move_constructible<_T1>::value &&
2371                   is_nothrow_move_constructible<_T2>::value)
2372        : _T1(_VSTD::move(__p.first())), _T2(_VSTD::move(__p.second())) {}
2373
2374    _LIBCPP_INLINE_VISIBILITY
2375    __libcpp_compressed_pair_imp& operator=(__libcpp_compressed_pair_imp&& __p)
2376        _NOEXCEPT_(is_nothrow_move_assignable<_T1>::value &&
2377                   is_nothrow_move_assignable<_T2>::value)
2378        {
2379            _T1::operator=(_VSTD::move(__p.first()));
2380            _T2::operator=(_VSTD::move(__p.second()));
2381            return *this;
2382        }
2383
2384#endif  // defined(_LIBCPP_HAS_NO_DEFAULTED_FUNCTIONS) && !defined(_LIBCPP_HAS_NO_RVALUE_REFERENCES)
2385
2386#ifndef _LIBCPP_HAS_NO_VARIADICS
2387
2388    template <class... _Args1, class... _Args2, size_t... _I1, size_t... _I2>
2389        _LIBCPP_INLINE_VISIBILITY
2390        __libcpp_compressed_pair_imp(piecewise_construct_t __pc,
2391                                     tuple<_Args1...> __first_args,
2392                                     tuple<_Args2...> __second_args,
2393                                     __tuple_indices<_I1...>,
2394                                     __tuple_indices<_I2...>)
2395            : _T1(_VSTD::forward<_Args1>(_VSTD::get<_I1>(__first_args))...),
2396              _T2(_VSTD::forward<_Args2>(_VSTD::get<_I2>(__second_args))...)
2397            {}
2398
2399#endif  // _LIBCPP_HAS_NO_VARIADICS
2400
2401    _LIBCPP_INLINE_VISIBILITY _T1_reference       first() _NOEXCEPT       {return *this;}
2402    _LIBCPP_INLINE_VISIBILITY _T1_const_reference first() const _NOEXCEPT {return *this;}
2403
2404    _LIBCPP_INLINE_VISIBILITY _T2_reference       second() _NOEXCEPT       {return *this;}
2405    _LIBCPP_INLINE_VISIBILITY _T2_const_reference second() const _NOEXCEPT {return *this;}
2406
2407    _LIBCPP_INLINE_VISIBILITY void swap(__libcpp_compressed_pair_imp&)
2408        _NOEXCEPT_(__is_nothrow_swappable<_T1>::value &&
2409                   __is_nothrow_swappable<_T2>::value)
2410    {
2411    }
2412};
2413
2414template <class _T1, class _T2>
2415class __compressed_pair
2416    : private __libcpp_compressed_pair_imp<_T1, _T2>
2417{
2418    typedef __libcpp_compressed_pair_imp<_T1, _T2> base;
2419public:
2420    typedef typename base::_T1_param _T1_param;
2421    typedef typename base::_T2_param _T2_param;
2422
2423    typedef typename base::_T1_reference _T1_reference;
2424    typedef typename base::_T2_reference _T2_reference;
2425
2426    typedef typename base::_T1_const_reference _T1_const_reference;
2427    typedef typename base::_T2_const_reference _T2_const_reference;
2428
2429    _LIBCPP_INLINE_VISIBILITY __compressed_pair() {}
2430    _LIBCPP_INLINE_VISIBILITY explicit __compressed_pair(_T1_param __t1)
2431        : base(_VSTD::forward<_T1_param>(__t1)) {}
2432    _LIBCPP_INLINE_VISIBILITY explicit __compressed_pair(_T2_param __t2)
2433        : base(_VSTD::forward<_T2_param>(__t2)) {}
2434    _LIBCPP_INLINE_VISIBILITY __compressed_pair(_T1_param __t1, _T2_param __t2)
2435        : base(_VSTD::forward<_T1_param>(__t1), _VSTD::forward<_T2_param>(__t2)) {}
2436
2437#if defined(_LIBCPP_HAS_NO_DEFAULTED_FUNCTIONS) && !defined(_LIBCPP_HAS_NO_RVALUE_REFERENCES)
2438
2439    _LIBCPP_INLINE_VISIBILITY
2440    __compressed_pair(const __compressed_pair& __p)
2441        _NOEXCEPT_(is_nothrow_copy_constructible<_T1>::value &&
2442                   is_nothrow_copy_constructible<_T2>::value)
2443        : base(__p) {}
2444
2445    _LIBCPP_INLINE_VISIBILITY
2446    __compressed_pair& operator=(const __compressed_pair& __p)
2447        _NOEXCEPT_(is_nothrow_copy_assignable<_T1>::value &&
2448                   is_nothrow_copy_assignable<_T2>::value)
2449        {
2450            base::operator=(__p);
2451            return *this;
2452        }
2453
2454    _LIBCPP_INLINE_VISIBILITY
2455    __compressed_pair(__compressed_pair&& __p)
2456        _NOEXCEPT_(is_nothrow_move_constructible<_T1>::value &&
2457                   is_nothrow_move_constructible<_T2>::value)
2458        : base(_VSTD::move(__p)) {}
2459
2460    _LIBCPP_INLINE_VISIBILITY
2461    __compressed_pair& operator=(__compressed_pair&& __p)
2462        _NOEXCEPT_(is_nothrow_move_assignable<_T1>::value &&
2463                   is_nothrow_move_assignable<_T2>::value)
2464        {
2465            base::operator=(_VSTD::move(__p));
2466            return *this;
2467        }
2468
2469#endif  // defined(_LIBCPP_HAS_NO_DEFAULTED_FUNCTIONS) && !defined(_LIBCPP_HAS_NO_RVALUE_REFERENCES)
2470
2471#ifndef _LIBCPP_HAS_NO_VARIADICS
2472
2473    template <class... _Args1, class... _Args2>
2474        _LIBCPP_INLINE_VISIBILITY
2475        __compressed_pair(piecewise_construct_t __pc, tuple<_Args1...> __first_args,
2476                                                      tuple<_Args2...> __second_args)
2477            : base(__pc, _VSTD::move(__first_args), _VSTD::move(__second_args),
2478                   typename __make_tuple_indices<sizeof...(_Args1)>::type(),
2479                   typename __make_tuple_indices<sizeof...(_Args2) >::type())
2480            {}
2481
2482#endif  // _LIBCPP_HAS_NO_VARIADICS
2483
2484    _LIBCPP_INLINE_VISIBILITY _T1_reference       first() _NOEXCEPT       {return base::first();}
2485    _LIBCPP_INLINE_VISIBILITY _T1_const_reference first() const _NOEXCEPT {return base::first();}
2486
2487    _LIBCPP_INLINE_VISIBILITY _T2_reference       second() _NOEXCEPT       {return base::second();}
2488    _LIBCPP_INLINE_VISIBILITY _T2_const_reference second() const _NOEXCEPT {return base::second();}
2489
2490    _LIBCPP_INLINE_VISIBILITY void swap(__compressed_pair& __x)
2491        _NOEXCEPT_(__is_nothrow_swappable<_T1>::value &&
2492                   __is_nothrow_swappable<_T2>::value)
2493        {base::swap(__x);}
2494};
2495
2496template <class _T1, class _T2>
2497inline _LIBCPP_INLINE_VISIBILITY
2498void
2499swap(__compressed_pair<_T1, _T2>& __x, __compressed_pair<_T1, _T2>& __y)
2500        _NOEXCEPT_(__is_nothrow_swappable<_T1>::value &&
2501                   __is_nothrow_swappable<_T2>::value)
2502    {__x.swap(__y);}
2503
2504// __same_or_less_cv_qualified
2505
2506template <class _Ptr1, class _Ptr2,
2507          bool = is_same<typename remove_cv<typename pointer_traits<_Ptr1>::element_type>::type,
2508                         typename remove_cv<typename pointer_traits<_Ptr2>::element_type>::type
2509                        >::value
2510         >
2511struct __same_or_less_cv_qualified_imp
2512    : is_convertible<_Ptr1, _Ptr2> {};
2513
2514template <class _Ptr1, class _Ptr2>
2515struct __same_or_less_cv_qualified_imp<_Ptr1, _Ptr2, false>
2516    : false_type {};
2517
2518template <class _Ptr1, class _Ptr2, bool = is_pointer<_Ptr1>::value ||
2519                                           is_same<_Ptr1, _Ptr2>::value ||
2520                                           __has_element_type<_Ptr1>::value>
2521struct __same_or_less_cv_qualified
2522    : __same_or_less_cv_qualified_imp<_Ptr1, _Ptr2> {};
2523
2524template <class _Ptr1, class _Ptr2>
2525struct __same_or_less_cv_qualified<_Ptr1, _Ptr2, false>
2526    : false_type {};
2527
2528// default_delete
2529
2530template <class _Tp>
2531struct _LIBCPP_TYPE_VIS_ONLY default_delete
2532{
2533#ifndef _LIBCPP_HAS_NO_DEFAULTED_FUNCTIONS
2534    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR default_delete() _NOEXCEPT = default;
2535#else
2536    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR default_delete() _NOEXCEPT {}
2537#endif
2538    template <class _Up>
2539        _LIBCPP_INLINE_VISIBILITY default_delete(const default_delete<_Up>&,
2540             typename enable_if<is_convertible<_Up*, _Tp*>::value>::type* = 0) _NOEXCEPT {}
2541    _LIBCPP_INLINE_VISIBILITY void operator() (_Tp* __ptr) const _NOEXCEPT
2542        {
2543            static_assert(sizeof(_Tp) > 0, "default_delete can not delete incomplete type");
2544            static_assert(!is_void<_Tp>::value, "default_delete can not delete incomplete type");
2545            delete __ptr;
2546        }
2547};
2548
2549template <class _Tp>
2550struct _LIBCPP_TYPE_VIS_ONLY default_delete<_Tp[]>
2551{
2552public:
2553#ifndef _LIBCPP_HAS_NO_DEFAULTED_FUNCTIONS
2554    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR default_delete() _NOEXCEPT = default;
2555#else
2556    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR default_delete() _NOEXCEPT {}
2557#endif
2558    template <class _Up>
2559        _LIBCPP_INLINE_VISIBILITY default_delete(const default_delete<_Up[]>&,
2560             typename enable_if<__same_or_less_cv_qualified<_Up*, _Tp*>::value>::type* = 0) _NOEXCEPT {}
2561    template <class _Up>
2562        _LIBCPP_INLINE_VISIBILITY
2563        void operator() (_Up* __ptr,
2564                         typename enable_if<__same_or_less_cv_qualified<_Up*, _Tp*>::value>::type* = 0) const _NOEXCEPT
2565        {
2566            static_assert(sizeof(_Tp) > 0, "default_delete can not delete incomplete type");
2567            static_assert(!is_void<_Tp>::value, "default_delete can not delete void type");
2568            delete [] __ptr;
2569        }
2570};
2571
2572template <class _Tp, class _Dp = default_delete<_Tp> >
2573class _LIBCPP_TYPE_VIS_ONLY unique_ptr
2574{
2575public:
2576    typedef _Tp element_type;
2577    typedef _Dp deleter_type;
2578    typedef typename __pointer_type<_Tp, deleter_type>::type pointer;
2579private:
2580    __compressed_pair<pointer, deleter_type> __ptr_;
2581
2582#ifdef _LIBCPP_HAS_NO_RVALUE_REFERENCES
2583    unique_ptr(unique_ptr&);
2584    template <class _Up, class _Ep>
2585        unique_ptr(unique_ptr<_Up, _Ep>&);
2586    unique_ptr& operator=(unique_ptr&);
2587    template <class _Up, class _Ep>
2588        unique_ptr& operator=(unique_ptr<_Up, _Ep>&);
2589#endif  // _LIBCPP_HAS_NO_RVALUE_REFERENCES
2590
2591    struct __nat {int __for_bool_;};
2592
2593    typedef       typename remove_reference<deleter_type>::type& _Dp_reference;
2594    typedef const typename remove_reference<deleter_type>::type& _Dp_const_reference;
2595public:
2596    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR unique_ptr() _NOEXCEPT
2597        : __ptr_(pointer())
2598        {
2599            static_assert(!is_pointer<deleter_type>::value,
2600                "unique_ptr constructed with null function pointer deleter");
2601        }
2602    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR unique_ptr(nullptr_t) _NOEXCEPT
2603        : __ptr_(pointer())
2604        {
2605            static_assert(!is_pointer<deleter_type>::value,
2606                "unique_ptr constructed with null function pointer deleter");
2607        }
2608    _LIBCPP_INLINE_VISIBILITY explicit unique_ptr(pointer __p) _NOEXCEPT
2609        : __ptr_(_VSTD::move(__p))
2610        {
2611            static_assert(!is_pointer<deleter_type>::value,
2612                "unique_ptr constructed with null function pointer deleter");
2613        }
2614
2615#ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES
2616    _LIBCPP_INLINE_VISIBILITY unique_ptr(pointer __p, typename conditional<
2617                                        is_reference<deleter_type>::value,
2618                                        deleter_type,
2619                                        typename add_lvalue_reference<const deleter_type>::type>::type __d)
2620             _NOEXCEPT
2621        : __ptr_(__p, __d) {}
2622
2623    _LIBCPP_INLINE_VISIBILITY unique_ptr(pointer __p, typename remove_reference<deleter_type>::type&& __d)
2624             _NOEXCEPT
2625        : __ptr_(__p, _VSTD::move(__d))
2626        {
2627            static_assert(!is_reference<deleter_type>::value, "rvalue deleter bound to reference");
2628        }
2629    _LIBCPP_INLINE_VISIBILITY unique_ptr(unique_ptr&& __u) _NOEXCEPT
2630        : __ptr_(__u.release(), _VSTD::forward<deleter_type>(__u.get_deleter())) {}
2631    template <class _Up, class _Ep>
2632        _LIBCPP_INLINE_VISIBILITY
2633        unique_ptr(unique_ptr<_Up, _Ep>&& __u,
2634                   typename enable_if
2635                      <
2636                        !is_array<_Up>::value &&
2637                         is_convertible<typename unique_ptr<_Up, _Ep>::pointer, pointer>::value &&
2638                         is_convertible<_Ep, deleter_type>::value &&
2639                         (
2640                            !is_reference<deleter_type>::value ||
2641                            is_same<deleter_type, _Ep>::value
2642                         ),
2643                         __nat
2644                      >::type = __nat()) _NOEXCEPT
2645            : __ptr_(__u.release(), _VSTD::forward<_Ep>(__u.get_deleter())) {}
2646
2647    template <class _Up>
2648        _LIBCPP_INLINE_VISIBILITY unique_ptr(auto_ptr<_Up>&& __p,
2649                typename enable_if<
2650                                      is_convertible<_Up*, _Tp*>::value &&
2651                                      is_same<_Dp, default_delete<_Tp> >::value,
2652                                      __nat
2653                                  >::type = __nat()) _NOEXCEPT
2654            : __ptr_(__p.release())
2655            {
2656            }
2657
2658        _LIBCPP_INLINE_VISIBILITY unique_ptr& operator=(unique_ptr&& __u) _NOEXCEPT
2659            {
2660                reset(__u.release());
2661                __ptr_.second() = _VSTD::forward<deleter_type>(__u.get_deleter());
2662                return *this;
2663            }
2664
2665        template <class _Up, class _Ep>
2666            _LIBCPP_INLINE_VISIBILITY
2667            typename enable_if
2668            <
2669                !is_array<_Up>::value &&
2670                is_convertible<typename unique_ptr<_Up, _Ep>::pointer, pointer>::value &&
2671                is_assignable<deleter_type&, _Ep&&>::value,
2672                unique_ptr&
2673            >::type
2674            operator=(unique_ptr<_Up, _Ep>&& __u) _NOEXCEPT
2675            {
2676                reset(__u.release());
2677                __ptr_.second() = _VSTD::forward<_Ep>(__u.get_deleter());
2678                return *this;
2679            }
2680#else  // _LIBCPP_HAS_NO_RVALUE_REFERENCES
2681
2682    _LIBCPP_INLINE_VISIBILITY operator __rv<unique_ptr>()
2683    {
2684        return __rv<unique_ptr>(*this);
2685    }
2686
2687    _LIBCPP_INLINE_VISIBILITY unique_ptr(__rv<unique_ptr> __u)
2688        : __ptr_(__u->release(), _VSTD::forward<deleter_type>(__u->get_deleter())) {}
2689
2690    template <class _Up, class _Ep>
2691    _LIBCPP_INLINE_VISIBILITY
2692    typename enable_if<
2693        !is_array<_Up>::value &&
2694        is_convertible<typename unique_ptr<_Up, _Ep>::pointer, pointer>::value &&
2695        is_assignable<deleter_type&, _Ep&>::value,
2696        unique_ptr&
2697    >::type
2698    operator=(unique_ptr<_Up, _Ep> __u)
2699    {
2700        reset(__u.release());
2701        __ptr_.second() = _VSTD::forward<_Ep>(__u.get_deleter());
2702        return *this;
2703    }
2704
2705    _LIBCPP_INLINE_VISIBILITY unique_ptr(pointer __p, deleter_type __d)
2706        : __ptr_(_VSTD::move(__p), _VSTD::move(__d)) {}
2707
2708    template <class _Up>
2709        _LIBCPP_INLINE_VISIBILITY
2710                typename enable_if<
2711                                      is_convertible<_Up*, _Tp*>::value &&
2712                                      is_same<_Dp, default_delete<_Tp> >::value,
2713                                      unique_ptr&
2714                                  >::type
2715        operator=(auto_ptr<_Up> __p)
2716            {reset(__p.release()); return *this;}
2717
2718#endif  // _LIBCPP_HAS_NO_RVALUE_REFERENCES
2719    _LIBCPP_INLINE_VISIBILITY ~unique_ptr() {reset();}
2720
2721    _LIBCPP_INLINE_VISIBILITY unique_ptr& operator=(nullptr_t) _NOEXCEPT
2722    {
2723        reset();
2724        return *this;
2725    }
2726
2727    _LIBCPP_INLINE_VISIBILITY typename add_lvalue_reference<_Tp>::type operator*() const
2728        {return *__ptr_.first();}
2729    _LIBCPP_INLINE_VISIBILITY pointer operator->() const _NOEXCEPT {return __ptr_.first();}
2730    _LIBCPP_INLINE_VISIBILITY pointer get() const _NOEXCEPT {return __ptr_.first();}
2731    _LIBCPP_INLINE_VISIBILITY       _Dp_reference get_deleter() _NOEXCEPT
2732        {return __ptr_.second();}
2733    _LIBCPP_INLINE_VISIBILITY _Dp_const_reference get_deleter() const _NOEXCEPT
2734        {return __ptr_.second();}
2735    _LIBCPP_INLINE_VISIBILITY
2736        _LIBCPP_EXPLICIT operator bool() const _NOEXCEPT
2737        {return __ptr_.first() != nullptr;}
2738
2739    _LIBCPP_INLINE_VISIBILITY pointer release() _NOEXCEPT
2740    {
2741        pointer __t = __ptr_.first();
2742        __ptr_.first() = pointer();
2743        return __t;
2744    }
2745
2746    _LIBCPP_INLINE_VISIBILITY void reset(pointer __p = pointer()) _NOEXCEPT
2747    {
2748        pointer __tmp = __ptr_.first();
2749        __ptr_.first() = __p;
2750        if (__tmp)
2751            __ptr_.second()(__tmp);
2752    }
2753
2754    _LIBCPP_INLINE_VISIBILITY void swap(unique_ptr& __u) _NOEXCEPT
2755        {__ptr_.swap(__u.__ptr_);}
2756};
2757
2758template <class _Tp, class _Dp>
2759class _LIBCPP_TYPE_VIS_ONLY unique_ptr<_Tp[], _Dp>
2760{
2761public:
2762    typedef _Tp element_type;
2763    typedef _Dp deleter_type;
2764    typedef typename __pointer_type<_Tp, deleter_type>::type pointer;
2765private:
2766    __compressed_pair<pointer, deleter_type> __ptr_;
2767
2768#ifdef _LIBCPP_HAS_NO_RVALUE_REFERENCES
2769    unique_ptr(unique_ptr&);
2770    template <class _Up>
2771        unique_ptr(unique_ptr<_Up>&);
2772    unique_ptr& operator=(unique_ptr&);
2773    template <class _Up>
2774        unique_ptr& operator=(unique_ptr<_Up>&);
2775#endif  // _LIBCPP_HAS_NO_RVALUE_REFERENCES
2776
2777    struct __nat {int __for_bool_;};
2778
2779    typedef       typename remove_reference<deleter_type>::type& _Dp_reference;
2780    typedef const typename remove_reference<deleter_type>::type& _Dp_const_reference;
2781public:
2782    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR unique_ptr() _NOEXCEPT
2783        : __ptr_(pointer())
2784        {
2785            static_assert(!is_pointer<deleter_type>::value,
2786                "unique_ptr constructed with null function pointer deleter");
2787        }
2788    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR unique_ptr(nullptr_t) _NOEXCEPT
2789        : __ptr_(pointer())
2790        {
2791            static_assert(!is_pointer<deleter_type>::value,
2792                "unique_ptr constructed with null function pointer deleter");
2793        }
2794#ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES
2795    template <class _Pp>
2796    _LIBCPP_INLINE_VISIBILITY explicit unique_ptr(_Pp __p,
2797            typename enable_if<__same_or_less_cv_qualified<_Pp, pointer>::value, __nat>::type = __nat()) _NOEXCEPT
2798        : __ptr_(__p)
2799        {
2800            static_assert(!is_pointer<deleter_type>::value,
2801                "unique_ptr constructed with null function pointer deleter");
2802        }
2803
2804    template <class _Pp>
2805    _LIBCPP_INLINE_VISIBILITY unique_ptr(_Pp __p, typename conditional<
2806                                       is_reference<deleter_type>::value,
2807                                       deleter_type,
2808                                       typename add_lvalue_reference<const deleter_type>::type>::type __d,
2809                                       typename enable_if<__same_or_less_cv_qualified<_Pp, pointer>::value, __nat>::type = __nat())
2810             _NOEXCEPT
2811        : __ptr_(__p, __d) {}
2812
2813    _LIBCPP_INLINE_VISIBILITY unique_ptr(nullptr_t, typename conditional<
2814                                       is_reference<deleter_type>::value,
2815                                       deleter_type,
2816                                       typename add_lvalue_reference<const deleter_type>::type>::type __d)
2817             _NOEXCEPT
2818        : __ptr_(pointer(), __d) {}
2819
2820    template <class _Pp>
2821    _LIBCPP_INLINE_VISIBILITY unique_ptr(_Pp __p,
2822                                         typename remove_reference<deleter_type>::type&& __d,
2823                                         typename enable_if<__same_or_less_cv_qualified<_Pp, pointer>::value, __nat>::type = __nat())
2824             _NOEXCEPT
2825        : __ptr_(__p, _VSTD::move(__d))
2826        {
2827            static_assert(!is_reference<deleter_type>::value, "rvalue deleter bound to reference");
2828        }
2829
2830    _LIBCPP_INLINE_VISIBILITY unique_ptr(nullptr_t, typename remove_reference<deleter_type>::type&& __d)
2831             _NOEXCEPT
2832        : __ptr_(pointer(), _VSTD::move(__d))
2833        {
2834            static_assert(!is_reference<deleter_type>::value, "rvalue deleter bound to reference");
2835        }
2836
2837    _LIBCPP_INLINE_VISIBILITY unique_ptr(unique_ptr&& __u) _NOEXCEPT
2838        : __ptr_(__u.release(), _VSTD::forward<deleter_type>(__u.get_deleter())) {}
2839
2840    _LIBCPP_INLINE_VISIBILITY unique_ptr& operator=(unique_ptr&& __u) _NOEXCEPT
2841        {
2842            reset(__u.release());
2843            __ptr_.second() = _VSTD::forward<deleter_type>(__u.get_deleter());
2844            return *this;
2845        }
2846
2847    template <class _Up, class _Ep>
2848        _LIBCPP_INLINE_VISIBILITY
2849        unique_ptr(unique_ptr<_Up, _Ep>&& __u,
2850                   typename enable_if
2851                            <
2852                                is_array<_Up>::value &&
2853                                __same_or_less_cv_qualified<typename unique_ptr<_Up, _Ep>::pointer, pointer>::value
2854                                && is_convertible<_Ep, deleter_type>::value &&
2855                                (
2856                                    !is_reference<deleter_type>::value ||
2857                                    is_same<deleter_type, _Ep>::value
2858                                ),
2859                                __nat
2860                            >::type = __nat()
2861                  ) _NOEXCEPT
2862        : __ptr_(__u.release(), _VSTD::forward<deleter_type>(__u.get_deleter())) {}
2863
2864
2865        template <class _Up, class _Ep>
2866            _LIBCPP_INLINE_VISIBILITY
2867            typename enable_if
2868            <
2869                is_array<_Up>::value &&
2870                __same_or_less_cv_qualified<typename unique_ptr<_Up, _Ep>::pointer, pointer>::value &&
2871                is_assignable<deleter_type&, _Ep&&>::value,
2872                unique_ptr&
2873            >::type
2874            operator=(unique_ptr<_Up, _Ep>&& __u) _NOEXCEPT
2875            {
2876                reset(__u.release());
2877                __ptr_.second() = _VSTD::forward<_Ep>(__u.get_deleter());
2878                return *this;
2879            }
2880#else  // _LIBCPP_HAS_NO_RVALUE_REFERENCES
2881
2882    _LIBCPP_INLINE_VISIBILITY explicit unique_ptr(pointer __p)
2883        : __ptr_(__p)
2884        {
2885            static_assert(!is_pointer<deleter_type>::value,
2886                "unique_ptr constructed with null function pointer deleter");
2887        }
2888
2889    _LIBCPP_INLINE_VISIBILITY unique_ptr(pointer __p, deleter_type __d)
2890        : __ptr_(__p, _VSTD::forward<deleter_type>(__d)) {}
2891
2892    _LIBCPP_INLINE_VISIBILITY unique_ptr(nullptr_t, deleter_type __d)
2893        : __ptr_(pointer(), _VSTD::forward<deleter_type>(__d)) {}
2894
2895    _LIBCPP_INLINE_VISIBILITY operator __rv<unique_ptr>()
2896    {
2897        return __rv<unique_ptr>(*this);
2898    }
2899
2900    _LIBCPP_INLINE_VISIBILITY unique_ptr(__rv<unique_ptr> __u)
2901        : __ptr_(__u->release(), _VSTD::forward<deleter_type>(__u->get_deleter())) {}
2902
2903    _LIBCPP_INLINE_VISIBILITY unique_ptr& operator=(__rv<unique_ptr> __u)
2904    {
2905        reset(__u->release());
2906        __ptr_.second() = _VSTD::forward<deleter_type>(__u->get_deleter());
2907        return *this;
2908    }
2909
2910#endif  // _LIBCPP_HAS_NO_RVALUE_REFERENCES
2911    _LIBCPP_INLINE_VISIBILITY ~unique_ptr() {reset();}
2912
2913    _LIBCPP_INLINE_VISIBILITY unique_ptr& operator=(nullptr_t) _NOEXCEPT
2914    {
2915        reset();
2916        return *this;
2917    }
2918
2919    _LIBCPP_INLINE_VISIBILITY typename add_lvalue_reference<_Tp>::type operator[](size_t __i) const
2920        {return __ptr_.first()[__i];}
2921    _LIBCPP_INLINE_VISIBILITY pointer get() const _NOEXCEPT {return __ptr_.first();}
2922    _LIBCPP_INLINE_VISIBILITY       _Dp_reference get_deleter() _NOEXCEPT
2923        {return __ptr_.second();}
2924    _LIBCPP_INLINE_VISIBILITY _Dp_const_reference get_deleter() const _NOEXCEPT
2925        {return __ptr_.second();}
2926    _LIBCPP_INLINE_VISIBILITY
2927        _LIBCPP_EXPLICIT operator bool() const _NOEXCEPT
2928        {return __ptr_.first() != nullptr;}
2929
2930    _LIBCPP_INLINE_VISIBILITY pointer release() _NOEXCEPT
2931    {
2932        pointer __t = __ptr_.first();
2933        __ptr_.first() = pointer();
2934        return __t;
2935    }
2936
2937    template <class _Pp>
2938    _LIBCPP_INLINE_VISIBILITY
2939    typename enable_if<__same_or_less_cv_qualified<_Pp, pointer>::value, void>::type
2940    reset(_Pp __p) _NOEXCEPT
2941    {
2942        pointer __tmp = __ptr_.first();
2943        __ptr_.first() = __p;
2944        if (__tmp)
2945            __ptr_.second()(__tmp);
2946    }
2947    _LIBCPP_INLINE_VISIBILITY void reset(nullptr_t = nullptr) _NOEXCEPT
2948    {
2949        pointer __tmp = __ptr_.first();
2950        __ptr_.first() = nullptr;
2951        if (__tmp)
2952            __ptr_.second()(__tmp);
2953    }
2954
2955    _LIBCPP_INLINE_VISIBILITY void swap(unique_ptr& __u) {__ptr_.swap(__u.__ptr_);}
2956private:
2957
2958#ifdef _LIBCPP_HAS_NO_RVALUE_REFERENCES
2959    template <class _Up>
2960        explicit unique_ptr(_Up);
2961    template <class _Up>
2962        unique_ptr(_Up __u,
2963                   typename conditional<
2964                                       is_reference<deleter_type>::value,
2965                                       deleter_type,
2966                                       typename add_lvalue_reference<const deleter_type>::type>::type,
2967                   typename enable_if
2968                      <
2969                         is_convertible<_Up, pointer>::value,
2970                         __nat
2971                      >::type = __nat());
2972#endif  // _LIBCPP_HAS_NO_RVALUE_REFERENCES
2973};
2974
2975template <class _Tp, class _Dp>
2976inline _LIBCPP_INLINE_VISIBILITY
2977void
2978swap(unique_ptr<_Tp, _Dp>& __x, unique_ptr<_Tp, _Dp>& __y) _NOEXCEPT {__x.swap(__y);}
2979
2980template <class _T1, class _D1, class _T2, class _D2>
2981inline _LIBCPP_INLINE_VISIBILITY
2982bool
2983operator==(const unique_ptr<_T1, _D1>& __x, const unique_ptr<_T2, _D2>& __y) {return __x.get() == __y.get();}
2984
2985template <class _T1, class _D1, class _T2, class _D2>
2986inline _LIBCPP_INLINE_VISIBILITY
2987bool
2988operator!=(const unique_ptr<_T1, _D1>& __x, const unique_ptr<_T2, _D2>& __y) {return !(__x == __y);}
2989
2990template <class _T1, class _D1, class _T2, class _D2>
2991inline _LIBCPP_INLINE_VISIBILITY
2992bool
2993operator< (const unique_ptr<_T1, _D1>& __x, const unique_ptr<_T2, _D2>& __y)
2994{
2995    typedef typename unique_ptr<_T1, _D1>::pointer _P1;
2996    typedef typename unique_ptr<_T2, _D2>::pointer _P2;
2997    typedef typename common_type<_P1, _P2>::type _Vp;
2998    return less<_Vp>()(__x.get(), __y.get());
2999}
3000
3001template <class _T1, class _D1, class _T2, class _D2>
3002inline _LIBCPP_INLINE_VISIBILITY
3003bool
3004operator> (const unique_ptr<_T1, _D1>& __x, const unique_ptr<_T2, _D2>& __y) {return __y < __x;}
3005
3006template <class _T1, class _D1, class _T2, class _D2>
3007inline _LIBCPP_INLINE_VISIBILITY
3008bool
3009operator<=(const unique_ptr<_T1, _D1>& __x, const unique_ptr<_T2, _D2>& __y) {return !(__y < __x);}
3010
3011template <class _T1, class _D1, class _T2, class _D2>
3012inline _LIBCPP_INLINE_VISIBILITY
3013bool
3014operator>=(const unique_ptr<_T1, _D1>& __x, const unique_ptr<_T2, _D2>& __y) {return !(__x < __y);}
3015
3016template <class _T1, class _D1>
3017inline _LIBCPP_INLINE_VISIBILITY
3018bool
3019operator==(const unique_ptr<_T1, _D1>& __x, nullptr_t) _NOEXCEPT
3020{
3021    return !__x;
3022}
3023
3024template <class _T1, class _D1>
3025inline _LIBCPP_INLINE_VISIBILITY
3026bool
3027operator==(nullptr_t, const unique_ptr<_T1, _D1>& __x) _NOEXCEPT
3028{
3029    return !__x;
3030}
3031
3032template <class _T1, class _D1>
3033inline _LIBCPP_INLINE_VISIBILITY
3034bool
3035operator!=(const unique_ptr<_T1, _D1>& __x, nullptr_t) _NOEXCEPT
3036{
3037    return static_cast<bool>(__x);
3038}
3039
3040template <class _T1, class _D1>
3041inline _LIBCPP_INLINE_VISIBILITY
3042bool
3043operator!=(nullptr_t, const unique_ptr<_T1, _D1>& __x) _NOEXCEPT
3044{
3045    return static_cast<bool>(__x);
3046}
3047
3048template <class _T1, class _D1>
3049inline _LIBCPP_INLINE_VISIBILITY
3050bool
3051operator<(const unique_ptr<_T1, _D1>& __x, nullptr_t)
3052{
3053    typedef typename unique_ptr<_T1, _D1>::pointer _P1;
3054    return less<_P1>()(__x.get(), nullptr);
3055}
3056
3057template <class _T1, class _D1>
3058inline _LIBCPP_INLINE_VISIBILITY
3059bool
3060operator<(nullptr_t, const unique_ptr<_T1, _D1>& __x)
3061{
3062    typedef typename unique_ptr<_T1, _D1>::pointer _P1;
3063    return less<_P1>()(nullptr, __x.get());
3064}
3065
3066template <class _T1, class _D1>
3067inline _LIBCPP_INLINE_VISIBILITY
3068bool
3069operator>(const unique_ptr<_T1, _D1>& __x, nullptr_t)
3070{
3071    return nullptr < __x;
3072}
3073
3074template <class _T1, class _D1>
3075inline _LIBCPP_INLINE_VISIBILITY
3076bool
3077operator>(nullptr_t, const unique_ptr<_T1, _D1>& __x)
3078{
3079    return __x < nullptr;
3080}
3081
3082template <class _T1, class _D1>
3083inline _LIBCPP_INLINE_VISIBILITY
3084bool
3085operator<=(const unique_ptr<_T1, _D1>& __x, nullptr_t)
3086{
3087    return !(nullptr < __x);
3088}
3089
3090template <class _T1, class _D1>
3091inline _LIBCPP_INLINE_VISIBILITY
3092bool
3093operator<=(nullptr_t, const unique_ptr<_T1, _D1>& __x)
3094{
3095    return !(__x < nullptr);
3096}
3097
3098template <class _T1, class _D1>
3099inline _LIBCPP_INLINE_VISIBILITY
3100bool
3101operator>=(const unique_ptr<_T1, _D1>& __x, nullptr_t)
3102{
3103    return !(__x < nullptr);
3104}
3105
3106template <class _T1, class _D1>
3107inline _LIBCPP_INLINE_VISIBILITY
3108bool
3109operator>=(nullptr_t, const unique_ptr<_T1, _D1>& __x)
3110{
3111    return !(nullptr < __x);
3112}
3113
3114#ifdef _LIBCPP_HAS_NO_RVALUE_REFERENCES
3115
3116template <class _Tp, class _Dp>
3117inline _LIBCPP_INLINE_VISIBILITY
3118unique_ptr<_Tp, _Dp>
3119move(unique_ptr<_Tp, _Dp>& __t)
3120{
3121    return unique_ptr<_Tp, _Dp>(__rv<unique_ptr<_Tp, _Dp> >(__t));
3122}
3123
3124#endif
3125
3126#if _LIBCPP_STD_VER > 11
3127
3128template<class _Tp>
3129struct __unique_if
3130{
3131    typedef unique_ptr<_Tp> __unique_single;
3132};
3133
3134template<class _Tp>
3135struct __unique_if<_Tp[]>
3136{
3137    typedef unique_ptr<_Tp[]> __unique_array_unknown_bound;
3138};
3139
3140template<class _Tp, size_t _Np>
3141struct __unique_if<_Tp[_Np]>
3142{
3143    typedef void __unique_array_known_bound;
3144};
3145
3146template<class _Tp, class... _Args>
3147inline _LIBCPP_INLINE_VISIBILITY
3148typename __unique_if<_Tp>::__unique_single
3149make_unique(_Args&&... __args)
3150{
3151    return unique_ptr<_Tp>(new _Tp(_VSTD::forward<_Args>(__args)...));
3152}
3153
3154template<class _Tp>
3155inline _LIBCPP_INLINE_VISIBILITY
3156typename __unique_if<_Tp>::__unique_array_unknown_bound
3157make_unique(size_t __n)
3158{
3159    typedef typename remove_extent<_Tp>::type _Up;
3160    return unique_ptr<_Tp>(new _Up[__n]());
3161}
3162
3163template<class _Tp, class... _Args>
3164    typename __unique_if<_Tp>::__unique_array_known_bound
3165    make_unique(_Args&&...) = delete;
3166
3167#endif  // _LIBCPP_STD_VER > 11
3168
3169template <class _Tp> struct hash;
3170
3171template <class _Size>
3172inline _LIBCPP_INLINE_VISIBILITY
3173_Size
3174__loadword(const void* __p)
3175{
3176    _Size __r;
3177    std::memcpy(&__r, __p, sizeof(__r));
3178    return __r;
3179}
3180
3181// We use murmur2 when size_t is 32 bits, and cityhash64 when size_t
3182// is 64 bits.  This is because cityhash64 uses 64bit x 64bit
3183// multiplication, which can be very slow on 32-bit systems.
3184template <class _Size, size_t = sizeof(_Size)*__CHAR_BIT__>
3185struct __murmur2_or_cityhash;
3186
3187template <class _Size>
3188struct __murmur2_or_cityhash<_Size, 32>
3189{
3190    _Size operator()(const void* __key, _Size __len);
3191};
3192
3193// murmur2
3194template <class _Size>
3195_Size
3196__murmur2_or_cityhash<_Size, 32>::operator()(const void* __key, _Size __len) _LIBCPP_DISABLE_UBSAN_UNSIGNED_INTEGER_CHECK
3197{
3198    const _Size __m = 0x5bd1e995;
3199    const _Size __r = 24;
3200    _Size __h = __len;
3201    const unsigned char* __data = static_cast<const unsigned char*>(__key);
3202    for (; __len >= 4; __data += 4, __len -= 4)
3203    {
3204        _Size __k = __loadword<_Size>(__data);
3205        __k *= __m;
3206        __k ^= __k >> __r;
3207        __k *= __m;
3208        __h *= __m;
3209        __h ^= __k;
3210    }
3211    switch (__len)
3212    {
3213    case 3:
3214        __h ^= __data[2] << 16;
3215    case 2:
3216        __h ^= __data[1] << 8;
3217    case 1:
3218        __h ^= __data[0];
3219        __h *= __m;
3220    }
3221    __h ^= __h >> 13;
3222    __h *= __m;
3223    __h ^= __h >> 15;
3224    return __h;
3225}
3226
3227template <class _Size>
3228struct __murmur2_or_cityhash<_Size, 64>
3229{
3230    _Size operator()(const void* __key, _Size __len);
3231
3232 private:
3233  // Some primes between 2^63 and 2^64.
3234  static const _Size __k0 = 0xc3a5c85c97cb3127ULL;
3235  static const _Size __k1 = 0xb492b66fbe98f273ULL;
3236  static const _Size __k2 = 0x9ae16a3b2f90404fULL;
3237  static const _Size __k3 = 0xc949d7c7509e6557ULL;
3238
3239  static _Size __rotate(_Size __val, int __shift) {
3240    return __shift == 0 ? __val : ((__val >> __shift) | (__val << (64 - __shift)));
3241  }
3242
3243  static _Size __rotate_by_at_least_1(_Size __val, int __shift) {
3244    return (__val >> __shift) | (__val << (64 - __shift));
3245  }
3246
3247  static _Size __shift_mix(_Size __val) {
3248    return __val ^ (__val >> 47);
3249  }
3250
3251  static _Size __hash_len_16(_Size __u, _Size __v) {
3252    const _Size __mul = 0x9ddfea08eb382d69ULL;
3253    _Size __a = (__u ^ __v) * __mul;
3254    __a ^= (__a >> 47);
3255    _Size __b = (__v ^ __a) * __mul;
3256    __b ^= (__b >> 47);
3257    __b *= __mul;
3258    return __b;
3259  }
3260
3261  static _Size __hash_len_0_to_16(const char* __s, _Size __len) {
3262    if (__len > 8) {
3263      const _Size __a = __loadword<_Size>(__s);
3264      const _Size __b = __loadword<_Size>(__s + __len - 8);
3265      return __hash_len_16(__a, __rotate_by_at_least_1(__b + __len, __len)) ^ __b;
3266    }
3267    if (__len >= 4) {
3268      const uint32_t __a = __loadword<uint32_t>(__s);
3269      const uint32_t __b = __loadword<uint32_t>(__s + __len - 4);
3270      return __hash_len_16(__len + (__a << 3), __b);
3271    }
3272    if (__len > 0) {
3273      const unsigned char __a = __s[0];
3274      const unsigned char __b = __s[__len >> 1];
3275      const unsigned char __c = __s[__len - 1];
3276      const uint32_t __y = static_cast<uint32_t>(__a) +
3277                           (static_cast<uint32_t>(__b) << 8);
3278      const uint32_t __z = __len + (static_cast<uint32_t>(__c) << 2);
3279      return __shift_mix(__y * __k2 ^ __z * __k3) * __k2;
3280    }
3281    return __k2;
3282  }
3283
3284  static _Size __hash_len_17_to_32(const char *__s, _Size __len) {
3285    const _Size __a = __loadword<_Size>(__s) * __k1;
3286    const _Size __b = __loadword<_Size>(__s + 8);
3287    const _Size __c = __loadword<_Size>(__s + __len - 8) * __k2;
3288    const _Size __d = __loadword<_Size>(__s + __len - 16) * __k0;
3289    return __hash_len_16(__rotate(__a - __b, 43) + __rotate(__c, 30) + __d,
3290                         __a + __rotate(__b ^ __k3, 20) - __c + __len);
3291  }
3292
3293  // Return a 16-byte hash for 48 bytes.  Quick and dirty.
3294  // Callers do best to use "random-looking" values for a and b.
3295  static pair<_Size, _Size> __weak_hash_len_32_with_seeds(
3296      _Size __w, _Size __x, _Size __y, _Size __z, _Size __a, _Size __b) {
3297    __a += __w;
3298    __b = __rotate(__b + __a + __z, 21);
3299    const _Size __c = __a;
3300    __a += __x;
3301    __a += __y;
3302    __b += __rotate(__a, 44);
3303    return pair<_Size, _Size>(__a + __z, __b + __c);
3304  }
3305
3306  // Return a 16-byte hash for s[0] ... s[31], a, and b.  Quick and dirty.
3307  static pair<_Size, _Size> __weak_hash_len_32_with_seeds(
3308      const char* __s, _Size __a, _Size __b) {
3309    return __weak_hash_len_32_with_seeds(__loadword<_Size>(__s),
3310                                         __loadword<_Size>(__s + 8),
3311                                         __loadword<_Size>(__s + 16),
3312                                         __loadword<_Size>(__s + 24),
3313                                         __a,
3314                                         __b);
3315  }
3316
3317  // Return an 8-byte hash for 33 to 64 bytes.
3318  static _Size __hash_len_33_to_64(const char *__s, size_t __len) {
3319    _Size __z = __loadword<_Size>(__s + 24);
3320    _Size __a = __loadword<_Size>(__s) +
3321                (__len + __loadword<_Size>(__s + __len - 16)) * __k0;
3322    _Size __b = __rotate(__a + __z, 52);
3323    _Size __c = __rotate(__a, 37);
3324    __a += __loadword<_Size>(__s + 8);
3325    __c += __rotate(__a, 7);
3326    __a += __loadword<_Size>(__s + 16);
3327    _Size __vf = __a + __z;
3328    _Size __vs = __b + __rotate(__a, 31) + __c;
3329    __a = __loadword<_Size>(__s + 16) + __loadword<_Size>(__s + __len - 32);
3330    __z += __loadword<_Size>(__s + __len - 8);
3331    __b = __rotate(__a + __z, 52);
3332    __c = __rotate(__a, 37);
3333    __a += __loadword<_Size>(__s + __len - 24);
3334    __c += __rotate(__a, 7);
3335    __a += __loadword<_Size>(__s + __len - 16);
3336    _Size __wf = __a + __z;
3337    _Size __ws = __b + __rotate(__a, 31) + __c;
3338    _Size __r = __shift_mix((__vf + __ws) * __k2 + (__wf + __vs) * __k0);
3339    return __shift_mix(__r * __k0 + __vs) * __k2;
3340  }
3341};
3342
3343// cityhash64
3344template <class _Size>
3345_Size
3346__murmur2_or_cityhash<_Size, 64>::operator()(const void* __key, _Size __len) _LIBCPP_DISABLE_UBSAN_UNSIGNED_INTEGER_CHECK
3347{
3348  const char* __s = static_cast<const char*>(__key);
3349  if (__len <= 32) {
3350    if (__len <= 16) {
3351      return __hash_len_0_to_16(__s, __len);
3352    } else {
3353      return __hash_len_17_to_32(__s, __len);
3354    }
3355  } else if (__len <= 64) {
3356    return __hash_len_33_to_64(__s, __len);
3357  }
3358
3359  // For strings over 64 bytes we hash the end first, and then as we
3360  // loop we keep 56 bytes of state: v, w, x, y, and z.
3361  _Size __x = __loadword<_Size>(__s + __len - 40);
3362  _Size __y = __loadword<_Size>(__s + __len - 16) +
3363              __loadword<_Size>(__s + __len - 56);
3364  _Size __z = __hash_len_16(__loadword<_Size>(__s + __len - 48) + __len,
3365                          __loadword<_Size>(__s + __len - 24));
3366  pair<_Size, _Size> __v = __weak_hash_len_32_with_seeds(__s + __len - 64, __len, __z);
3367  pair<_Size, _Size> __w = __weak_hash_len_32_with_seeds(__s + __len - 32, __y + __k1, __x);
3368  __x = __x * __k1 + __loadword<_Size>(__s);
3369
3370  // Decrease len to the nearest multiple of 64, and operate on 64-byte chunks.
3371  __len = (__len - 1) & ~static_cast<_Size>(63);
3372  do {
3373    __x = __rotate(__x + __y + __v.first + __loadword<_Size>(__s + 8), 37) * __k1;
3374    __y = __rotate(__y + __v.second + __loadword<_Size>(__s + 48), 42) * __k1;
3375    __x ^= __w.second;
3376    __y += __v.first + __loadword<_Size>(__s + 40);
3377    __z = __rotate(__z + __w.first, 33) * __k1;
3378    __v = __weak_hash_len_32_with_seeds(__s, __v.second * __k1, __x + __w.first);
3379    __w = __weak_hash_len_32_with_seeds(__s + 32, __z + __w.second,
3380                                        __y + __loadword<_Size>(__s + 16));
3381    std::swap(__z, __x);
3382    __s += 64;
3383    __len -= 64;
3384  } while (__len != 0);
3385  return __hash_len_16(
3386      __hash_len_16(__v.first, __w.first) + __shift_mix(__y) * __k1 + __z,
3387      __hash_len_16(__v.second, __w.second) + __x);
3388}
3389
3390template <class _Tp, size_t = sizeof(_Tp) / sizeof(size_t)>
3391struct __scalar_hash;
3392
3393template <class _Tp>
3394struct __scalar_hash<_Tp, 0>
3395    : public unary_function<_Tp, size_t>
3396{
3397    _LIBCPP_INLINE_VISIBILITY
3398    size_t operator()(_Tp __v) const _NOEXCEPT
3399    {
3400        union
3401        {
3402            _Tp    __t;
3403            size_t __a;
3404        } __u;
3405        __u.__a = 0;
3406        __u.__t = __v;
3407        return __u.__a;
3408    }
3409};
3410
3411template <class _Tp>
3412struct __scalar_hash<_Tp, 1>
3413    : public unary_function<_Tp, size_t>
3414{
3415    _LIBCPP_INLINE_VISIBILITY
3416    size_t operator()(_Tp __v) const _NOEXCEPT
3417    {
3418        union
3419        {
3420            _Tp    __t;
3421            size_t __a;
3422        } __u;
3423        __u.__t = __v;
3424        return __u.__a;
3425    }
3426};
3427
3428template <class _Tp>
3429struct __scalar_hash<_Tp, 2>
3430    : public unary_function<_Tp, size_t>
3431{
3432    _LIBCPP_INLINE_VISIBILITY
3433    size_t operator()(_Tp __v) const _NOEXCEPT
3434    {
3435        union
3436        {
3437            _Tp __t;
3438            struct
3439            {
3440                size_t __a;
3441                size_t __b;
3442            } __s;
3443        } __u;
3444        __u.__t = __v;
3445        return __murmur2_or_cityhash<size_t>()(&__u, sizeof(__u));
3446    }
3447};
3448
3449template <class _Tp>
3450struct __scalar_hash<_Tp, 3>
3451    : public unary_function<_Tp, size_t>
3452{
3453    _LIBCPP_INLINE_VISIBILITY
3454    size_t operator()(_Tp __v) const _NOEXCEPT
3455    {
3456        union
3457        {
3458            _Tp __t;
3459            struct
3460            {
3461                size_t __a;
3462                size_t __b;
3463                size_t __c;
3464            } __s;
3465        } __u;
3466        __u.__t = __v;
3467        return __murmur2_or_cityhash<size_t>()(&__u, sizeof(__u));
3468    }
3469};
3470
3471template <class _Tp>
3472struct __scalar_hash<_Tp, 4>
3473    : public unary_function<_Tp, size_t>
3474{
3475    _LIBCPP_INLINE_VISIBILITY
3476    size_t operator()(_Tp __v) const _NOEXCEPT
3477    {
3478        union
3479        {
3480            _Tp __t;
3481            struct
3482            {
3483                size_t __a;
3484                size_t __b;
3485                size_t __c;
3486                size_t __d;
3487            } __s;
3488        } __u;
3489        __u.__t = __v;
3490        return __murmur2_or_cityhash<size_t>()(&__u, sizeof(__u));
3491    }
3492};
3493
3494template<class _Tp>
3495struct _LIBCPP_TYPE_VIS_ONLY hash<_Tp*>
3496    : public unary_function<_Tp*, size_t>
3497{
3498    _LIBCPP_INLINE_VISIBILITY
3499    size_t operator()(_Tp* __v) const _NOEXCEPT
3500    {
3501        union
3502        {
3503            _Tp* __t;
3504            size_t __a;
3505        } __u;
3506        __u.__t = __v;
3507        return __murmur2_or_cityhash<size_t>()(&__u, sizeof(__u));
3508    }
3509};
3510
3511template <class _Tp, class _Dp>
3512struct _LIBCPP_TYPE_VIS_ONLY hash<unique_ptr<_Tp, _Dp> >
3513{
3514    typedef unique_ptr<_Tp, _Dp> argument_type;
3515    typedef size_t               result_type;
3516    _LIBCPP_INLINE_VISIBILITY
3517    result_type operator()(const argument_type& __ptr) const _NOEXCEPT
3518    {
3519        typedef typename argument_type::pointer pointer;
3520        return hash<pointer>()(__ptr.get());
3521    }
3522};
3523
3524struct __destruct_n
3525{
3526private:
3527    size_t size;
3528
3529    template <class _Tp>
3530    _LIBCPP_INLINE_VISIBILITY void __process(_Tp* __p, false_type) _NOEXCEPT
3531        {for (size_t __i = 0; __i < size; ++__i, ++__p) __p->~_Tp();}
3532
3533    template <class _Tp>
3534    _LIBCPP_INLINE_VISIBILITY void __process(_Tp*, true_type) _NOEXCEPT
3535        {}
3536
3537    _LIBCPP_INLINE_VISIBILITY void __incr(false_type) _NOEXCEPT
3538        {++size;}
3539    _LIBCPP_INLINE_VISIBILITY void __incr(true_type) _NOEXCEPT
3540        {}
3541
3542    _LIBCPP_INLINE_VISIBILITY void __set(size_t __s, false_type) _NOEXCEPT
3543        {size = __s;}
3544    _LIBCPP_INLINE_VISIBILITY void __set(size_t, true_type) _NOEXCEPT
3545        {}
3546public:
3547    _LIBCPP_INLINE_VISIBILITY explicit __destruct_n(size_t __s) _NOEXCEPT
3548        : size(__s) {}
3549
3550    template <class _Tp>
3551    _LIBCPP_INLINE_VISIBILITY void __incr(_Tp*) _NOEXCEPT
3552        {__incr(integral_constant<bool, is_trivially_destructible<_Tp>::value>());}
3553
3554    template <class _Tp>
3555    _LIBCPP_INLINE_VISIBILITY void __set(size_t __s, _Tp*) _NOEXCEPT
3556        {__set(__s, integral_constant<bool, is_trivially_destructible<_Tp>::value>());}
3557
3558    template <class _Tp>
3559    _LIBCPP_INLINE_VISIBILITY void operator()(_Tp* __p) _NOEXCEPT
3560        {__process(__p, integral_constant<bool, is_trivially_destructible<_Tp>::value>());}
3561};
3562
3563template <class _Alloc>
3564class __allocator_destructor
3565{
3566    typedef allocator_traits<_Alloc> __alloc_traits;
3567public:
3568    typedef typename __alloc_traits::pointer pointer;
3569    typedef typename __alloc_traits::size_type size_type;
3570private:
3571    _Alloc& __alloc_;
3572    size_type __s_;
3573public:
3574    _LIBCPP_INLINE_VISIBILITY __allocator_destructor(_Alloc& __a, size_type __s)
3575             _NOEXCEPT
3576        : __alloc_(__a), __s_(__s) {}
3577    _LIBCPP_INLINE_VISIBILITY
3578    void operator()(pointer __p) _NOEXCEPT
3579        {__alloc_traits::deallocate(__alloc_, __p, __s_);}
3580};
3581
3582template <class _InputIterator, class _ForwardIterator>
3583_ForwardIterator
3584uninitialized_copy(_InputIterator __f, _InputIterator __l, _ForwardIterator __r)
3585{
3586    typedef typename iterator_traits<_ForwardIterator>::value_type value_type;
3587#ifndef _LIBCPP_NO_EXCEPTIONS
3588    _ForwardIterator __s = __r;
3589    try
3590    {
3591#endif
3592        for (; __f != __l; ++__f, (void) ++__r)
3593            ::new (static_cast<void*>(_VSTD::addressof(*__r))) value_type(*__f);
3594#ifndef _LIBCPP_NO_EXCEPTIONS
3595    }
3596    catch (...)
3597    {
3598        for (; __s != __r; ++__s)
3599            __s->~value_type();
3600        throw;
3601    }
3602#endif
3603    return __r;
3604}
3605
3606template <class _InputIterator, class _Size, class _ForwardIterator>
3607_ForwardIterator
3608uninitialized_copy_n(_InputIterator __f, _Size __n, _ForwardIterator __r)
3609{
3610    typedef typename iterator_traits<_ForwardIterator>::value_type value_type;
3611#ifndef _LIBCPP_NO_EXCEPTIONS
3612    _ForwardIterator __s = __r;
3613    try
3614    {
3615#endif
3616        for (; __n > 0; ++__f, (void) ++__r, (void) --__n)
3617            ::new (static_cast<void*>(_VSTD::addressof(*__r))) value_type(*__f);
3618#ifndef _LIBCPP_NO_EXCEPTIONS
3619    }
3620    catch (...)
3621    {
3622        for (; __s != __r; ++__s)
3623            __s->~value_type();
3624        throw;
3625    }
3626#endif
3627    return __r;
3628}
3629
3630template <class _ForwardIterator, class _Tp>
3631void
3632uninitialized_fill(_ForwardIterator __f, _ForwardIterator __l, const _Tp& __x)
3633{
3634    typedef typename iterator_traits<_ForwardIterator>::value_type value_type;
3635#ifndef _LIBCPP_NO_EXCEPTIONS
3636    _ForwardIterator __s = __f;
3637    try
3638    {
3639#endif
3640        for (; __f != __l; ++__f)
3641            ::new (static_cast<void*>(_VSTD::addressof(*__f))) value_type(__x);
3642#ifndef _LIBCPP_NO_EXCEPTIONS
3643    }
3644    catch (...)
3645    {
3646        for (; __s != __f; ++__s)
3647            __s->~value_type();
3648        throw;
3649    }
3650#endif
3651}
3652
3653template <class _ForwardIterator, class _Size, class _Tp>
3654_ForwardIterator
3655uninitialized_fill_n(_ForwardIterator __f, _Size __n, const _Tp& __x)
3656{
3657    typedef typename iterator_traits<_ForwardIterator>::value_type value_type;
3658#ifndef _LIBCPP_NO_EXCEPTIONS
3659    _ForwardIterator __s = __f;
3660    try
3661    {
3662#endif
3663        for (; __n > 0; ++__f, (void) --__n)
3664            ::new (static_cast<void*>(_VSTD::addressof(*__f))) value_type(__x);
3665#ifndef _LIBCPP_NO_EXCEPTIONS
3666    }
3667    catch (...)
3668    {
3669        for (; __s != __f; ++__s)
3670            __s->~value_type();
3671        throw;
3672    }
3673#endif
3674    return __f;
3675}
3676
3677class _LIBCPP_EXCEPTION_ABI bad_weak_ptr
3678    : public std::exception
3679{
3680public:
3681    virtual ~bad_weak_ptr() _NOEXCEPT;
3682    virtual const char* what() const  _NOEXCEPT;
3683};
3684
3685template<class _Tp> class _LIBCPP_TYPE_VIS_ONLY weak_ptr;
3686
3687class _LIBCPP_TYPE_VIS __shared_count
3688{
3689    __shared_count(const __shared_count&);
3690    __shared_count& operator=(const __shared_count&);
3691
3692protected:
3693    long __shared_owners_;
3694    virtual ~__shared_count();
3695private:
3696    virtual void __on_zero_shared() _NOEXCEPT = 0;
3697
3698public:
3699    _LIBCPP_INLINE_VISIBILITY
3700    explicit __shared_count(long __refs = 0) _NOEXCEPT
3701        : __shared_owners_(__refs) {}
3702
3703    void __add_shared() _NOEXCEPT;
3704    bool __release_shared() _NOEXCEPT;
3705    _LIBCPP_INLINE_VISIBILITY
3706    long use_count() const _NOEXCEPT {
3707        return __libcpp_relaxed_load(&__shared_owners_) + 1;
3708    }
3709};
3710
3711class _LIBCPP_TYPE_VIS __shared_weak_count
3712    : private __shared_count
3713{
3714    long __shared_weak_owners_;
3715
3716public:
3717    _LIBCPP_INLINE_VISIBILITY
3718    explicit __shared_weak_count(long __refs = 0) _NOEXCEPT
3719        : __shared_count(__refs),
3720          __shared_weak_owners_(__refs) {}
3721protected:
3722    virtual ~__shared_weak_count();
3723
3724public:
3725    void __add_shared() _NOEXCEPT;
3726    void __add_weak() _NOEXCEPT;
3727    void __release_shared() _NOEXCEPT;
3728    void __release_weak() _NOEXCEPT;
3729    _LIBCPP_INLINE_VISIBILITY
3730    long use_count() const _NOEXCEPT {return __shared_count::use_count();}
3731    __shared_weak_count* lock() _NOEXCEPT;
3732
3733    // Define the function out only if we build static libc++ without RTTI.
3734    // Otherwise we may break clients who need to compile their projects with
3735    // -fno-rtti and yet link against a libc++.dylib compiled
3736    // without -fno-rtti.
3737#if !defined(_LIBCPP_NO_RTTI) || !defined(_LIBCPP_BUILD_STATIC)
3738    virtual const void* __get_deleter(const type_info&) const _NOEXCEPT;
3739#endif
3740private:
3741    virtual void __on_zero_shared_weak() _NOEXCEPT = 0;
3742};
3743
3744template <class _Tp, class _Dp, class _Alloc>
3745class __shared_ptr_pointer
3746    : public __shared_weak_count
3747{
3748    __compressed_pair<__compressed_pair<_Tp, _Dp>, _Alloc> __data_;
3749public:
3750    _LIBCPP_INLINE_VISIBILITY
3751    __shared_ptr_pointer(_Tp __p, _Dp __d, _Alloc __a)
3752        :  __data_(__compressed_pair<_Tp, _Dp>(__p, _VSTD::move(__d)), _VSTD::move(__a)) {}
3753
3754#ifndef _LIBCPP_NO_RTTI
3755    virtual const void* __get_deleter(const type_info&) const _NOEXCEPT;
3756#endif
3757
3758private:
3759    virtual void __on_zero_shared() _NOEXCEPT;
3760    virtual void __on_zero_shared_weak() _NOEXCEPT;
3761};
3762
3763#ifndef _LIBCPP_NO_RTTI
3764
3765template <class _Tp, class _Dp, class _Alloc>
3766const void*
3767__shared_ptr_pointer<_Tp, _Dp, _Alloc>::__get_deleter(const type_info& __t) const _NOEXCEPT
3768{
3769    return __t == typeid(_Dp) ? _VSTD::addressof(__data_.first().second()) : 0;
3770}
3771
3772#endif  // _LIBCPP_NO_RTTI
3773
3774template <class _Tp, class _Dp, class _Alloc>
3775void
3776__shared_ptr_pointer<_Tp, _Dp, _Alloc>::__on_zero_shared() _NOEXCEPT
3777{
3778    __data_.first().second()(__data_.first().first());
3779    __data_.first().second().~_Dp();
3780}
3781
3782template <class _Tp, class _Dp, class _Alloc>
3783void
3784__shared_ptr_pointer<_Tp, _Dp, _Alloc>::__on_zero_shared_weak() _NOEXCEPT
3785{
3786    typedef typename __allocator_traits_rebind<_Alloc, __shared_ptr_pointer>::type _Al;
3787    typedef allocator_traits<_Al> _ATraits;
3788    typedef pointer_traits<typename _ATraits::pointer> _PTraits;
3789
3790    _Al __a(__data_.second());
3791    __data_.second().~_Alloc();
3792    __a.deallocate(_PTraits::pointer_to(*this), 1);
3793}
3794
3795template <class _Tp, class _Alloc>
3796class __shared_ptr_emplace
3797    : public __shared_weak_count
3798{
3799    __compressed_pair<_Alloc, _Tp> __data_;
3800public:
3801#ifndef _LIBCPP_HAS_NO_VARIADICS
3802
3803    _LIBCPP_INLINE_VISIBILITY
3804    __shared_ptr_emplace(_Alloc __a)
3805        :  __data_(_VSTD::move(__a)) {}
3806
3807    template <class ..._Args>
3808        _LIBCPP_INLINE_VISIBILITY
3809        __shared_ptr_emplace(_Alloc __a, _Args&& ...__args)
3810            :  __data_(piecewise_construct, _VSTD::forward_as_tuple(__a),
3811                   _VSTD::forward_as_tuple(_VSTD::forward<_Args>(__args)...)) {}
3812
3813#else  // _LIBCPP_HAS_NO_VARIADICS
3814
3815    _LIBCPP_INLINE_VISIBILITY
3816    __shared_ptr_emplace(_Alloc __a)
3817        :  __data_(__a) {}
3818
3819    template <class _A0>
3820        _LIBCPP_INLINE_VISIBILITY
3821        __shared_ptr_emplace(_Alloc __a, _A0& __a0)
3822            :  __data_(__a, _Tp(__a0)) {}
3823
3824    template <class _A0, class _A1>
3825        _LIBCPP_INLINE_VISIBILITY
3826        __shared_ptr_emplace(_Alloc __a, _A0& __a0, _A1& __a1)
3827            :  __data_(__a, _Tp(__a0, __a1)) {}
3828
3829    template <class _A0, class _A1, class _A2>
3830        _LIBCPP_INLINE_VISIBILITY
3831        __shared_ptr_emplace(_Alloc __a, _A0& __a0, _A1& __a1, _A2& __a2)
3832            :  __data_(__a, _Tp(__a0, __a1, __a2)) {}
3833
3834#endif  // _LIBCPP_HAS_NO_VARIADICS
3835
3836private:
3837    virtual void __on_zero_shared() _NOEXCEPT;
3838    virtual void __on_zero_shared_weak() _NOEXCEPT;
3839public:
3840    _LIBCPP_INLINE_VISIBILITY
3841    _Tp* get() _NOEXCEPT {return &__data_.second();}
3842};
3843
3844template <class _Tp, class _Alloc>
3845void
3846__shared_ptr_emplace<_Tp, _Alloc>::__on_zero_shared() _NOEXCEPT
3847{
3848    __data_.second().~_Tp();
3849}
3850
3851template <class _Tp, class _Alloc>
3852void
3853__shared_ptr_emplace<_Tp, _Alloc>::__on_zero_shared_weak() _NOEXCEPT
3854{
3855    typedef typename __allocator_traits_rebind<_Alloc, __shared_ptr_emplace>::type _Al;
3856    typedef allocator_traits<_Al> _ATraits;
3857    typedef pointer_traits<typename _ATraits::pointer> _PTraits;
3858    _Al __a(__data_.first());
3859    __data_.first().~_Alloc();
3860    __a.deallocate(_PTraits::pointer_to(*this), 1);
3861}
3862
3863template<class _Tp> class _LIBCPP_TYPE_VIS_ONLY enable_shared_from_this;
3864
3865template<class _Tp>
3866class _LIBCPP_TYPE_VIS_ONLY shared_ptr
3867{
3868public:
3869    typedef _Tp element_type;
3870private:
3871    element_type*      __ptr_;
3872    __shared_weak_count* __cntrl_;
3873
3874    struct __nat {int __for_bool_;};
3875public:
3876    _LIBCPP_INLINE_VISIBILITY
3877    _LIBCPP_CONSTEXPR shared_ptr() _NOEXCEPT;
3878    _LIBCPP_INLINE_VISIBILITY
3879    _LIBCPP_CONSTEXPR shared_ptr(nullptr_t) _NOEXCEPT;
3880    template<class _Yp>
3881        explicit shared_ptr(_Yp* __p,
3882                            typename enable_if<is_convertible<_Yp*, element_type*>::value, __nat>::type = __nat());
3883    template<class _Yp, class _Dp>
3884        shared_ptr(_Yp* __p, _Dp __d,
3885                   typename enable_if<is_convertible<_Yp*, element_type*>::value, __nat>::type = __nat());
3886    template<class _Yp, class _Dp, class _Alloc>
3887        shared_ptr(_Yp* __p, _Dp __d, _Alloc __a,
3888                   typename enable_if<is_convertible<_Yp*, element_type*>::value, __nat>::type = __nat());
3889    template <class _Dp> shared_ptr(nullptr_t __p, _Dp __d);
3890    template <class _Dp, class _Alloc> shared_ptr(nullptr_t __p, _Dp __d, _Alloc __a);
3891    template<class _Yp> _LIBCPP_INLINE_VISIBILITY shared_ptr(const shared_ptr<_Yp>& __r, element_type* __p) _NOEXCEPT;
3892    _LIBCPP_INLINE_VISIBILITY
3893    shared_ptr(const shared_ptr& __r) _NOEXCEPT;
3894    template<class _Yp>
3895        _LIBCPP_INLINE_VISIBILITY
3896        shared_ptr(const shared_ptr<_Yp>& __r,
3897                   typename enable_if<is_convertible<_Yp*, _Tp*>::value, __nat>::type = __nat())
3898                       _NOEXCEPT;
3899#ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES
3900    _LIBCPP_INLINE_VISIBILITY
3901    shared_ptr(shared_ptr&& __r) _NOEXCEPT;
3902    template<class _Yp> _LIBCPP_INLINE_VISIBILITY  shared_ptr(shared_ptr<_Yp>&& __r,
3903                   typename enable_if<is_convertible<_Yp*, _Tp*>::value, __nat>::type = __nat())
3904                       _NOEXCEPT;
3905#endif  // _LIBCPP_HAS_NO_RVALUE_REFERENCES
3906    template<class _Yp> explicit shared_ptr(const weak_ptr<_Yp>& __r,
3907                   typename enable_if<is_convertible<_Yp*, _Tp*>::value, __nat>::type= __nat());
3908#ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES
3909    template<class _Yp>
3910        shared_ptr(auto_ptr<_Yp>&& __r,
3911                   typename enable_if<is_convertible<_Yp*, element_type*>::value, __nat>::type = __nat());
3912#else
3913    template<class _Yp>
3914        shared_ptr(auto_ptr<_Yp> __r,
3915                   typename enable_if<is_convertible<_Yp*, element_type*>::value, __nat>::type = __nat());
3916#endif
3917#ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES
3918    template <class _Yp, class _Dp>
3919        shared_ptr(unique_ptr<_Yp, _Dp>&&,
3920                   typename enable_if
3921                   <
3922                       !is_lvalue_reference<_Dp>::value &&
3923                       !is_array<_Yp>::value &&
3924                       is_convertible<typename unique_ptr<_Yp, _Dp>::pointer, element_type*>::value,
3925                       __nat
3926                   >::type = __nat());
3927    template <class _Yp, class _Dp>
3928        shared_ptr(unique_ptr<_Yp, _Dp>&&,
3929                   typename enable_if
3930                   <
3931                       is_lvalue_reference<_Dp>::value &&
3932                       !is_array<_Yp>::value &&
3933                       is_convertible<typename unique_ptr<_Yp, _Dp>::pointer, element_type*>::value,
3934                       __nat
3935                   >::type = __nat());
3936#else  // _LIBCPP_HAS_NO_RVALUE_REFERENCES
3937    template <class _Yp, class _Dp>
3938        shared_ptr(unique_ptr<_Yp, _Dp>,
3939                   typename enable_if
3940                   <
3941                       !is_lvalue_reference<_Dp>::value &&
3942                       !is_array<_Yp>::value &&
3943                       is_convertible<typename unique_ptr<_Yp, _Dp>::pointer, element_type*>::value,
3944                       __nat
3945                   >::type = __nat());
3946    template <class _Yp, class _Dp>
3947        shared_ptr(unique_ptr<_Yp, _Dp>,
3948                   typename enable_if
3949                   <
3950                       is_lvalue_reference<_Dp>::value &&
3951                       !is_array<_Yp>::value &&
3952                       is_convertible<typename unique_ptr<_Yp, _Dp>::pointer, element_type*>::value,
3953                       __nat
3954                   >::type = __nat());
3955#endif  // _LIBCPP_HAS_NO_RVALUE_REFERENCES
3956
3957    ~shared_ptr();
3958
3959    _LIBCPP_INLINE_VISIBILITY
3960    shared_ptr& operator=(const shared_ptr& __r) _NOEXCEPT;
3961    template<class _Yp>
3962        typename enable_if
3963        <
3964            is_convertible<_Yp*, element_type*>::value,
3965            shared_ptr&
3966        >::type
3967        _LIBCPP_INLINE_VISIBILITY
3968        operator=(const shared_ptr<_Yp>& __r) _NOEXCEPT;
3969#ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES
3970    _LIBCPP_INLINE_VISIBILITY
3971    shared_ptr& operator=(shared_ptr&& __r) _NOEXCEPT;
3972    template<class _Yp>
3973        typename enable_if
3974        <
3975            is_convertible<_Yp*, element_type*>::value,
3976            shared_ptr<_Tp>&
3977        >::type
3978        _LIBCPP_INLINE_VISIBILITY
3979        operator=(shared_ptr<_Yp>&& __r);
3980    template<class _Yp>
3981        typename enable_if
3982        <
3983            !is_array<_Yp>::value &&
3984            is_convertible<_Yp*, element_type*>::value,
3985            shared_ptr
3986        >::type&
3987        _LIBCPP_INLINE_VISIBILITY
3988        operator=(auto_ptr<_Yp>&& __r);
3989#else  // _LIBCPP_HAS_NO_RVALUE_REFERENCES
3990    template<class _Yp>
3991        typename enable_if
3992        <
3993            !is_array<_Yp>::value &&
3994            is_convertible<_Yp*, element_type*>::value,
3995            shared_ptr&
3996        >::type
3997        _LIBCPP_INLINE_VISIBILITY
3998        operator=(auto_ptr<_Yp> __r);
3999#endif
4000    template <class _Yp, class _Dp>
4001        typename enable_if
4002        <
4003            !is_array<_Yp>::value &&
4004            is_convertible<typename unique_ptr<_Yp, _Dp>::pointer, element_type*>::value,
4005            shared_ptr&
4006        >::type
4007#ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES
4008        _LIBCPP_INLINE_VISIBILITY
4009        operator=(unique_ptr<_Yp, _Dp>&& __r);
4010#else  // _LIBCPP_HAS_NO_RVALUE_REFERENCES
4011        _LIBCPP_INLINE_VISIBILITY
4012        operator=(unique_ptr<_Yp, _Dp> __r);
4013#endif
4014
4015    _LIBCPP_INLINE_VISIBILITY
4016    void swap(shared_ptr& __r) _NOEXCEPT;
4017    _LIBCPP_INLINE_VISIBILITY
4018    void reset() _NOEXCEPT;
4019    template<class _Yp>
4020        typename enable_if
4021        <
4022            is_convertible<_Yp*, element_type*>::value,
4023            void
4024        >::type
4025        _LIBCPP_INLINE_VISIBILITY
4026        reset(_Yp* __p);
4027    template<class _Yp, class _Dp>
4028        typename enable_if
4029        <
4030            is_convertible<_Yp*, element_type*>::value,
4031            void
4032        >::type
4033        _LIBCPP_INLINE_VISIBILITY
4034        reset(_Yp* __p, _Dp __d);
4035    template<class _Yp, class _Dp, class _Alloc>
4036        typename enable_if
4037        <
4038            is_convertible<_Yp*, element_type*>::value,
4039            void
4040        >::type
4041        _LIBCPP_INLINE_VISIBILITY
4042        reset(_Yp* __p, _Dp __d, _Alloc __a);
4043
4044    _LIBCPP_INLINE_VISIBILITY
4045    element_type* get() const _NOEXCEPT {return __ptr_;}
4046    _LIBCPP_INLINE_VISIBILITY
4047    typename add_lvalue_reference<element_type>::type operator*() const _NOEXCEPT
4048        {return *__ptr_;}
4049    _LIBCPP_INLINE_VISIBILITY
4050    element_type* operator->() const _NOEXCEPT {return __ptr_;}
4051    _LIBCPP_INLINE_VISIBILITY
4052    long use_count() const _NOEXCEPT {return __cntrl_ ? __cntrl_->use_count() : 0;}
4053    _LIBCPP_INLINE_VISIBILITY
4054    bool unique() const _NOEXCEPT {return use_count() == 1;}
4055    _LIBCPP_INLINE_VISIBILITY
4056    _LIBCPP_EXPLICIT operator bool() const _NOEXCEPT {return get() != 0;}
4057    template <class _Up>
4058        _LIBCPP_INLINE_VISIBILITY
4059        bool owner_before(shared_ptr<_Up> const& __p) const
4060        {return __cntrl_ < __p.__cntrl_;}
4061    template <class _Up>
4062        _LIBCPP_INLINE_VISIBILITY
4063        bool owner_before(weak_ptr<_Up> const& __p) const
4064        {return __cntrl_ < __p.__cntrl_;}
4065    _LIBCPP_INLINE_VISIBILITY
4066    bool
4067    __owner_equivalent(const shared_ptr& __p) const
4068        {return __cntrl_ == __p.__cntrl_;}
4069
4070#ifndef _LIBCPP_NO_RTTI
4071    template <class _Dp>
4072        _LIBCPP_INLINE_VISIBILITY
4073        _Dp* __get_deleter() const _NOEXCEPT
4074            {return (_Dp*)(__cntrl_ ? __cntrl_->__get_deleter(typeid(_Dp)) : 0);}
4075#endif  // _LIBCPP_NO_RTTI
4076
4077#ifndef _LIBCPP_HAS_NO_VARIADICS
4078
4079    template<class ..._Args>
4080        static
4081        shared_ptr<_Tp>
4082        make_shared(_Args&& ...__args);
4083
4084    template<class _Alloc, class ..._Args>
4085        static
4086        shared_ptr<_Tp>
4087        allocate_shared(const _Alloc& __a, _Args&& ...__args);
4088
4089#else  // _LIBCPP_HAS_NO_VARIADICS
4090
4091    static shared_ptr<_Tp> make_shared();
4092
4093    template<class _A0>
4094        static shared_ptr<_Tp> make_shared(_A0&);
4095
4096    template<class _A0, class _A1>
4097        static shared_ptr<_Tp> make_shared(_A0&, _A1&);
4098
4099    template<class _A0, class _A1, class _A2>
4100        static shared_ptr<_Tp> make_shared(_A0&, _A1&, _A2&);
4101
4102    template<class _Alloc>
4103        static shared_ptr<_Tp>
4104        allocate_shared(const _Alloc& __a);
4105
4106    template<class _Alloc, class _A0>
4107        static shared_ptr<_Tp>
4108        allocate_shared(const _Alloc& __a, _A0& __a0);
4109
4110    template<class _Alloc, class _A0, class _A1>
4111        static shared_ptr<_Tp>
4112        allocate_shared(const _Alloc& __a, _A0& __a0, _A1& __a1);
4113
4114    template<class _Alloc, class _A0, class _A1, class _A2>
4115        static shared_ptr<_Tp>
4116        allocate_shared(const _Alloc& __a, _A0& __a0, _A1& __a1, _A2& __a2);
4117
4118#endif  // _LIBCPP_HAS_NO_VARIADICS
4119
4120private:
4121
4122    template <class _Yp>
4123        _LIBCPP_INLINE_VISIBILITY
4124        void
4125        __enable_weak_this(const enable_shared_from_this<_Yp>* __e) _NOEXCEPT
4126        {
4127            if (__e)
4128            {
4129                __e->__weak_this_.__ptr_ = const_cast<_Yp*>(static_cast<const _Yp*>(__e));
4130                __e->__weak_this_.__cntrl_ = __cntrl_;
4131                __cntrl_->__add_weak();
4132            }
4133        }
4134
4135    _LIBCPP_INLINE_VISIBILITY
4136    void __enable_weak_this(const volatile void*) _NOEXCEPT {}
4137
4138    template <class _Up> friend class _LIBCPP_TYPE_VIS_ONLY shared_ptr;
4139    template <class _Up> friend class _LIBCPP_TYPE_VIS_ONLY weak_ptr;
4140};
4141
4142template<class _Tp>
4143inline
4144_LIBCPP_CONSTEXPR
4145shared_ptr<_Tp>::shared_ptr() _NOEXCEPT
4146    : __ptr_(0),
4147      __cntrl_(0)
4148{
4149}
4150
4151template<class _Tp>
4152inline
4153_LIBCPP_CONSTEXPR
4154shared_ptr<_Tp>::shared_ptr(nullptr_t) _NOEXCEPT
4155    : __ptr_(0),
4156      __cntrl_(0)
4157{
4158}
4159
4160template<class _Tp>
4161template<class _Yp>
4162shared_ptr<_Tp>::shared_ptr(_Yp* __p,
4163                            typename enable_if<is_convertible<_Yp*, element_type*>::value, __nat>::type)
4164    : __ptr_(__p)
4165{
4166    unique_ptr<_Yp> __hold(__p);
4167    typedef __shared_ptr_pointer<_Yp*, default_delete<_Yp>, allocator<_Yp> > _CntrlBlk;
4168    __cntrl_ = new _CntrlBlk(__p, default_delete<_Yp>(), allocator<_Yp>());
4169    __hold.release();
4170    __enable_weak_this(__p);
4171}
4172
4173template<class _Tp>
4174template<class _Yp, class _Dp>
4175shared_ptr<_Tp>::shared_ptr(_Yp* __p, _Dp __d,
4176                            typename enable_if<is_convertible<_Yp*, element_type*>::value, __nat>::type)
4177    : __ptr_(__p)
4178{
4179#ifndef _LIBCPP_NO_EXCEPTIONS
4180    try
4181    {
4182#endif  // _LIBCPP_NO_EXCEPTIONS
4183        typedef __shared_ptr_pointer<_Yp*, _Dp, allocator<_Yp> > _CntrlBlk;
4184        __cntrl_ = new _CntrlBlk(__p, __d, allocator<_Yp>());
4185        __enable_weak_this(__p);
4186#ifndef _LIBCPP_NO_EXCEPTIONS
4187    }
4188    catch (...)
4189    {
4190        __d(__p);
4191        throw;
4192    }
4193#endif  // _LIBCPP_NO_EXCEPTIONS
4194}
4195
4196template<class _Tp>
4197template<class _Dp>
4198shared_ptr<_Tp>::shared_ptr(nullptr_t __p, _Dp __d)
4199    : __ptr_(0)
4200{
4201#ifndef _LIBCPP_NO_EXCEPTIONS
4202    try
4203    {
4204#endif  // _LIBCPP_NO_EXCEPTIONS
4205        typedef __shared_ptr_pointer<nullptr_t, _Dp, allocator<_Tp> > _CntrlBlk;
4206        __cntrl_ = new _CntrlBlk(__p, __d, allocator<_Tp>());
4207#ifndef _LIBCPP_NO_EXCEPTIONS
4208    }
4209    catch (...)
4210    {
4211        __d(__p);
4212        throw;
4213    }
4214#endif  // _LIBCPP_NO_EXCEPTIONS
4215}
4216
4217template<class _Tp>
4218template<class _Yp, class _Dp, class _Alloc>
4219shared_ptr<_Tp>::shared_ptr(_Yp* __p, _Dp __d, _Alloc __a,
4220                            typename enable_if<is_convertible<_Yp*, element_type*>::value, __nat>::type)
4221    : __ptr_(__p)
4222{
4223#ifndef _LIBCPP_NO_EXCEPTIONS
4224    try
4225    {
4226#endif  // _LIBCPP_NO_EXCEPTIONS
4227        typedef __shared_ptr_pointer<_Yp*, _Dp, _Alloc> _CntrlBlk;
4228        typedef typename __allocator_traits_rebind<_Alloc, _CntrlBlk>::type _A2;
4229        typedef __allocator_destructor<_A2> _D2;
4230        _A2 __a2(__a);
4231        unique_ptr<_CntrlBlk, _D2> __hold2(__a2.allocate(1), _D2(__a2, 1));
4232        ::new(static_cast<void*>(_VSTD::addressof(*__hold2.get())))
4233            _CntrlBlk(__p, __d, __a);
4234        __cntrl_ = _VSTD::addressof(*__hold2.release());
4235        __enable_weak_this(__p);
4236#ifndef _LIBCPP_NO_EXCEPTIONS
4237    }
4238    catch (...)
4239    {
4240        __d(__p);
4241        throw;
4242    }
4243#endif  // _LIBCPP_NO_EXCEPTIONS
4244}
4245
4246template<class _Tp>
4247template<class _Dp, class _Alloc>
4248shared_ptr<_Tp>::shared_ptr(nullptr_t __p, _Dp __d, _Alloc __a)
4249    : __ptr_(0)
4250{
4251#ifndef _LIBCPP_NO_EXCEPTIONS
4252    try
4253    {
4254#endif  // _LIBCPP_NO_EXCEPTIONS
4255        typedef __shared_ptr_pointer<nullptr_t, _Dp, _Alloc> _CntrlBlk;
4256        typedef typename __allocator_traits_rebind<_Alloc, _CntrlBlk>::type _A2;
4257        typedef __allocator_destructor<_A2> _D2;
4258        _A2 __a2(__a);
4259        unique_ptr<_CntrlBlk, _D2> __hold2(__a2.allocate(1), _D2(__a2, 1));
4260        ::new(static_cast<void*>(_VSTD::addressof(*__hold2.get())))
4261            _CntrlBlk(__p, __d, __a);
4262        __cntrl_ = _VSTD::addressof(*__hold2.release());
4263#ifndef _LIBCPP_NO_EXCEPTIONS
4264    }
4265    catch (...)
4266    {
4267        __d(__p);
4268        throw;
4269    }
4270#endif  // _LIBCPP_NO_EXCEPTIONS
4271}
4272
4273template<class _Tp>
4274template<class _Yp>
4275inline
4276shared_ptr<_Tp>::shared_ptr(const shared_ptr<_Yp>& __r, element_type *__p) _NOEXCEPT
4277    : __ptr_(__p),
4278      __cntrl_(__r.__cntrl_)
4279{
4280    if (__cntrl_)
4281        __cntrl_->__add_shared();
4282}
4283
4284template<class _Tp>
4285inline
4286shared_ptr<_Tp>::shared_ptr(const shared_ptr& __r) _NOEXCEPT
4287    : __ptr_(__r.__ptr_),
4288      __cntrl_(__r.__cntrl_)
4289{
4290    if (__cntrl_)
4291        __cntrl_->__add_shared();
4292}
4293
4294template<class _Tp>
4295template<class _Yp>
4296inline
4297shared_ptr<_Tp>::shared_ptr(const shared_ptr<_Yp>& __r,
4298                            typename enable_if<is_convertible<_Yp*, _Tp*>::value, __nat>::type)
4299         _NOEXCEPT
4300    : __ptr_(__r.__ptr_),
4301      __cntrl_(__r.__cntrl_)
4302{
4303    if (__cntrl_)
4304        __cntrl_->__add_shared();
4305}
4306
4307#ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES
4308
4309template<class _Tp>
4310inline
4311shared_ptr<_Tp>::shared_ptr(shared_ptr&& __r) _NOEXCEPT
4312    : __ptr_(__r.__ptr_),
4313      __cntrl_(__r.__cntrl_)
4314{
4315    __r.__ptr_ = 0;
4316    __r.__cntrl_ = 0;
4317}
4318
4319template<class _Tp>
4320template<class _Yp>
4321inline
4322shared_ptr<_Tp>::shared_ptr(shared_ptr<_Yp>&& __r,
4323                            typename enable_if<is_convertible<_Yp*, _Tp*>::value, __nat>::type)
4324         _NOEXCEPT
4325    : __ptr_(__r.__ptr_),
4326      __cntrl_(__r.__cntrl_)
4327{
4328    __r.__ptr_ = 0;
4329    __r.__cntrl_ = 0;
4330}
4331
4332#endif  // _LIBCPP_HAS_NO_RVALUE_REFERENCES
4333
4334template<class _Tp>
4335template<class _Yp>
4336#ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES
4337shared_ptr<_Tp>::shared_ptr(auto_ptr<_Yp>&& __r,
4338#else
4339shared_ptr<_Tp>::shared_ptr(auto_ptr<_Yp> __r,
4340#endif
4341                            typename enable_if<is_convertible<_Yp*, element_type*>::value, __nat>::type)
4342    : __ptr_(__r.get())
4343{
4344    typedef __shared_ptr_pointer<_Yp*, default_delete<_Yp>, allocator<_Yp> > _CntrlBlk;
4345    __cntrl_ = new _CntrlBlk(__r.get(), default_delete<_Yp>(), allocator<_Yp>());
4346    __enable_weak_this(__r.get());
4347    __r.release();
4348}
4349
4350template<class _Tp>
4351template <class _Yp, class _Dp>
4352#ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES
4353shared_ptr<_Tp>::shared_ptr(unique_ptr<_Yp, _Dp>&& __r,
4354#else
4355shared_ptr<_Tp>::shared_ptr(unique_ptr<_Yp, _Dp> __r,
4356#endif
4357                            typename enable_if
4358                            <
4359                                !is_lvalue_reference<_Dp>::value &&
4360                                !is_array<_Yp>::value &&
4361                                is_convertible<typename unique_ptr<_Yp, _Dp>::pointer, element_type*>::value,
4362                                __nat
4363                            >::type)
4364    : __ptr_(__r.get())
4365{
4366#if _LIBCPP_STD_VER > 11
4367    if (__ptr_ == nullptr)
4368        __cntrl_ = nullptr;
4369    else
4370#endif
4371    {
4372        typedef __shared_ptr_pointer<_Yp*, _Dp, allocator<_Yp> > _CntrlBlk;
4373        __cntrl_ = new _CntrlBlk(__r.get(), __r.get_deleter(), allocator<_Yp>());
4374        __enable_weak_this(__r.get());
4375    }
4376    __r.release();
4377}
4378
4379template<class _Tp>
4380template <class _Yp, class _Dp>
4381#ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES
4382shared_ptr<_Tp>::shared_ptr(unique_ptr<_Yp, _Dp>&& __r,
4383#else
4384shared_ptr<_Tp>::shared_ptr(unique_ptr<_Yp, _Dp> __r,
4385#endif
4386                            typename enable_if
4387                            <
4388                                is_lvalue_reference<_Dp>::value &&
4389                                !is_array<_Yp>::value &&
4390                                is_convertible<typename unique_ptr<_Yp, _Dp>::pointer, element_type*>::value,
4391                                __nat
4392                            >::type)
4393    : __ptr_(__r.get())
4394{
4395#if _LIBCPP_STD_VER > 11
4396    if (__ptr_ == nullptr)
4397        __cntrl_ = nullptr;
4398    else
4399#endif
4400    {
4401        typedef __shared_ptr_pointer<_Yp*,
4402                                     reference_wrapper<typename remove_reference<_Dp>::type>,
4403                                     allocator<_Yp> > _CntrlBlk;
4404        __cntrl_ = new _CntrlBlk(__r.get(), ref(__r.get_deleter()), allocator<_Yp>());
4405        __enable_weak_this(__r.get());
4406    }
4407    __r.release();
4408}
4409
4410#ifndef _LIBCPP_HAS_NO_VARIADICS
4411
4412template<class _Tp>
4413template<class ..._Args>
4414shared_ptr<_Tp>
4415shared_ptr<_Tp>::make_shared(_Args&& ...__args)
4416{
4417    typedef __shared_ptr_emplace<_Tp, allocator<_Tp> > _CntrlBlk;
4418    typedef allocator<_CntrlBlk> _A2;
4419    typedef __allocator_destructor<_A2> _D2;
4420    _A2 __a2;
4421    unique_ptr<_CntrlBlk, _D2> __hold2(__a2.allocate(1), _D2(__a2, 1));
4422    ::new(__hold2.get()) _CntrlBlk(__a2, _VSTD::forward<_Args>(__args)...);
4423    shared_ptr<_Tp> __r;
4424    __r.__ptr_ = __hold2.get()->get();
4425    __r.__cntrl_ = __hold2.release();
4426    __r.__enable_weak_this(__r.__ptr_);
4427    return __r;
4428}
4429
4430template<class _Tp>
4431template<class _Alloc, class ..._Args>
4432shared_ptr<_Tp>
4433shared_ptr<_Tp>::allocate_shared(const _Alloc& __a, _Args&& ...__args)
4434{
4435    typedef __shared_ptr_emplace<_Tp, _Alloc> _CntrlBlk;
4436    typedef typename __allocator_traits_rebind<_Alloc, _CntrlBlk>::type _A2;
4437    typedef __allocator_destructor<_A2> _D2;
4438    _A2 __a2(__a);
4439    unique_ptr<_CntrlBlk, _D2> __hold2(__a2.allocate(1), _D2(__a2, 1));
4440    ::new(static_cast<void*>(_VSTD::addressof(*__hold2.get())))
4441        _CntrlBlk(__a, _VSTD::forward<_Args>(__args)...);
4442    shared_ptr<_Tp> __r;
4443    __r.__ptr_ = __hold2.get()->get();
4444    __r.__cntrl_ = _VSTD::addressof(*__hold2.release());
4445    __r.__enable_weak_this(__r.__ptr_);
4446    return __r;
4447}
4448
4449#else  // _LIBCPP_HAS_NO_VARIADICS
4450
4451template<class _Tp>
4452shared_ptr<_Tp>
4453shared_ptr<_Tp>::make_shared()
4454{
4455    typedef __shared_ptr_emplace<_Tp, allocator<_Tp> > _CntrlBlk;
4456    typedef allocator<_CntrlBlk> _Alloc2;
4457    typedef __allocator_destructor<_Alloc2> _D2;
4458    _Alloc2 __alloc2;
4459    unique_ptr<_CntrlBlk, _D2> __hold2(__alloc2.allocate(1), _D2(__alloc2, 1));
4460    ::new(__hold2.get()) _CntrlBlk(__alloc2);
4461    shared_ptr<_Tp> __r;
4462    __r.__ptr_ = __hold2.get()->get();
4463    __r.__cntrl_ = __hold2.release();
4464    __r.__enable_weak_this(__r.__ptr_);
4465    return __r;
4466}
4467
4468template<class _Tp>
4469template<class _A0>
4470shared_ptr<_Tp>
4471shared_ptr<_Tp>::make_shared(_A0& __a0)
4472{
4473    typedef __shared_ptr_emplace<_Tp, allocator<_Tp> > _CntrlBlk;
4474    typedef allocator<_CntrlBlk> _Alloc2;
4475    typedef __allocator_destructor<_Alloc2> _D2;
4476    _Alloc2 __alloc2;
4477    unique_ptr<_CntrlBlk, _D2> __hold2(__alloc2.allocate(1), _D2(__alloc2, 1));
4478    ::new(__hold2.get()) _CntrlBlk(__alloc2, __a0);
4479    shared_ptr<_Tp> __r;
4480    __r.__ptr_ = __hold2.get()->get();
4481    __r.__cntrl_ = __hold2.release();
4482    __r.__enable_weak_this(__r.__ptr_);
4483    return __r;
4484}
4485
4486template<class _Tp>
4487template<class _A0, class _A1>
4488shared_ptr<_Tp>
4489shared_ptr<_Tp>::make_shared(_A0& __a0, _A1& __a1)
4490{
4491    typedef __shared_ptr_emplace<_Tp, allocator<_Tp> > _CntrlBlk;
4492    typedef allocator<_CntrlBlk> _Alloc2;
4493    typedef __allocator_destructor<_Alloc2> _D2;
4494    _Alloc2 __alloc2;
4495    unique_ptr<_CntrlBlk, _D2> __hold2(__alloc2.allocate(1), _D2(__alloc2, 1));
4496    ::new(__hold2.get()) _CntrlBlk(__alloc2, __a0, __a1);
4497    shared_ptr<_Tp> __r;
4498    __r.__ptr_ = __hold2.get()->get();
4499    __r.__cntrl_ = __hold2.release();
4500    __r.__enable_weak_this(__r.__ptr_);
4501    return __r;
4502}
4503
4504template<class _Tp>
4505template<class _A0, class _A1, class _A2>
4506shared_ptr<_Tp>
4507shared_ptr<_Tp>::make_shared(_A0& __a0, _A1& __a1, _A2& __a2)
4508{
4509    typedef __shared_ptr_emplace<_Tp, allocator<_Tp> > _CntrlBlk;
4510    typedef allocator<_CntrlBlk> _Alloc2;
4511    typedef __allocator_destructor<_Alloc2> _D2;
4512    _Alloc2 __alloc2;
4513    unique_ptr<_CntrlBlk, _D2> __hold2(__alloc2.allocate(1), _D2(__alloc2, 1));
4514    ::new(__hold2.get()) _CntrlBlk(__alloc2, __a0, __a1, __a2);
4515    shared_ptr<_Tp> __r;
4516    __r.__ptr_ = __hold2.get()->get();
4517    __r.__cntrl_ = __hold2.release();
4518    __r.__enable_weak_this(__r.__ptr_);
4519    return __r;
4520}
4521
4522template<class _Tp>
4523template<class _Alloc>
4524shared_ptr<_Tp>
4525shared_ptr<_Tp>::allocate_shared(const _Alloc& __a)
4526{
4527    typedef __shared_ptr_emplace<_Tp, _Alloc> _CntrlBlk;
4528    typedef typename __allocator_traits_rebind<_Alloc, _CntrlBlk>::type _Alloc2;
4529    typedef __allocator_destructor<_Alloc2> _D2;
4530    _Alloc2 __alloc2(__a);
4531    unique_ptr<_CntrlBlk, _D2> __hold2(__alloc2.allocate(1), _D2(__alloc2, 1));
4532    ::new(static_cast<void*>(_VSTD::addressof(*__hold2.get())))
4533        _CntrlBlk(__a);
4534    shared_ptr<_Tp> __r;
4535    __r.__ptr_ = __hold2.get()->get();
4536    __r.__cntrl_ = _VSTD::addressof(*__hold2.release());
4537    __r.__enable_weak_this(__r.__ptr_);
4538    return __r;
4539}
4540
4541template<class _Tp>
4542template<class _Alloc, class _A0>
4543shared_ptr<_Tp>
4544shared_ptr<_Tp>::allocate_shared(const _Alloc& __a, _A0& __a0)
4545{
4546    typedef __shared_ptr_emplace<_Tp, _Alloc> _CntrlBlk;
4547    typedef typename __allocator_traits_rebind<_Alloc, _CntrlBlk>::type _Alloc2;
4548    typedef __allocator_destructor<_Alloc2> _D2;
4549    _Alloc2 __alloc2(__a);
4550    unique_ptr<_CntrlBlk, _D2> __hold2(__alloc2.allocate(1), _D2(__alloc2, 1));
4551    ::new(static_cast<void*>(_VSTD::addressof(*__hold2.get())))
4552        _CntrlBlk(__a, __a0);
4553    shared_ptr<_Tp> __r;
4554    __r.__ptr_ = __hold2.get()->get();
4555    __r.__cntrl_ = _VSTD::addressof(*__hold2.release());
4556    __r.__enable_weak_this(__r.__ptr_);
4557    return __r;
4558}
4559
4560template<class _Tp>
4561template<class _Alloc, class _A0, class _A1>
4562shared_ptr<_Tp>
4563shared_ptr<_Tp>::allocate_shared(const _Alloc& __a, _A0& __a0, _A1& __a1)
4564{
4565    typedef __shared_ptr_emplace<_Tp, _Alloc> _CntrlBlk;
4566    typedef typename __allocator_traits_rebind<_Alloc, _CntrlBlk>::type _Alloc2;
4567    typedef __allocator_destructor<_Alloc2> _D2;
4568    _Alloc2 __alloc2(__a);
4569    unique_ptr<_CntrlBlk, _D2> __hold2(__alloc2.allocate(1), _D2(__alloc2, 1));
4570    ::new(static_cast<void*>(_VSTD::addressof(*__hold2.get())))
4571        _CntrlBlk(__a, __a0, __a1);
4572    shared_ptr<_Tp> __r;
4573    __r.__ptr_ = __hold2.get()->get();
4574    __r.__cntrl_ = _VSTD::addressof(*__hold2.release());
4575    __r.__enable_weak_this(__r.__ptr_);
4576    return __r;
4577}
4578
4579template<class _Tp>
4580template<class _Alloc, class _A0, class _A1, class _A2>
4581shared_ptr<_Tp>
4582shared_ptr<_Tp>::allocate_shared(const _Alloc& __a, _A0& __a0, _A1& __a1, _A2& __a2)
4583{
4584    typedef __shared_ptr_emplace<_Tp, _Alloc> _CntrlBlk;
4585    typedef typename __allocator_traits_rebind<_Alloc, _CntrlBlk>::type _Alloc2;
4586    typedef __allocator_destructor<_Alloc2> _D2;
4587    _Alloc2 __alloc2(__a);
4588    unique_ptr<_CntrlBlk, _D2> __hold2(__alloc2.allocate(1), _D2(__alloc2, 1));
4589    ::new(static_cast<void*>(_VSTD::addressof(*__hold2.get())))
4590        _CntrlBlk(__a, __a0, __a1, __a2);
4591    shared_ptr<_Tp> __r;
4592    __r.__ptr_ = __hold2.get()->get();
4593    __r.__cntrl_ = _VSTD::addressof(*__hold2.release());
4594    __r.__enable_weak_this(__r.__ptr_);
4595    return __r;
4596}
4597
4598#endif  // _LIBCPP_HAS_NO_VARIADICS
4599
4600template<class _Tp>
4601shared_ptr<_Tp>::~shared_ptr()
4602{
4603    if (__cntrl_)
4604        __cntrl_->__release_shared();
4605}
4606
4607template<class _Tp>
4608inline
4609shared_ptr<_Tp>&
4610shared_ptr<_Tp>::operator=(const shared_ptr& __r) _NOEXCEPT
4611{
4612    shared_ptr(__r).swap(*this);
4613    return *this;
4614}
4615
4616template<class _Tp>
4617template<class _Yp>
4618inline
4619typename enable_if
4620<
4621    is_convertible<_Yp*, _Tp*>::value,
4622    shared_ptr<_Tp>&
4623>::type
4624shared_ptr<_Tp>::operator=(const shared_ptr<_Yp>& __r) _NOEXCEPT
4625{
4626    shared_ptr(__r).swap(*this);
4627    return *this;
4628}
4629
4630#ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES
4631
4632template<class _Tp>
4633inline
4634shared_ptr<_Tp>&
4635shared_ptr<_Tp>::operator=(shared_ptr&& __r) _NOEXCEPT
4636{
4637    shared_ptr(_VSTD::move(__r)).swap(*this);
4638    return *this;
4639}
4640
4641template<class _Tp>
4642template<class _Yp>
4643inline
4644typename enable_if
4645<
4646    is_convertible<_Yp*, _Tp*>::value,
4647    shared_ptr<_Tp>&
4648>::type
4649shared_ptr<_Tp>::operator=(shared_ptr<_Yp>&& __r)
4650{
4651    shared_ptr(_VSTD::move(__r)).swap(*this);
4652    return *this;
4653}
4654
4655template<class _Tp>
4656template<class _Yp>
4657inline
4658typename enable_if
4659<
4660    !is_array<_Yp>::value &&
4661    is_convertible<_Yp*, _Tp*>::value,
4662    shared_ptr<_Tp>
4663>::type&
4664shared_ptr<_Tp>::operator=(auto_ptr<_Yp>&& __r)
4665{
4666    shared_ptr(_VSTD::move(__r)).swap(*this);
4667    return *this;
4668}
4669
4670template<class _Tp>
4671template <class _Yp, class _Dp>
4672inline
4673typename enable_if
4674<
4675    !is_array<_Yp>::value &&
4676    is_convertible<typename unique_ptr<_Yp, _Dp>::pointer, _Tp*>::value,
4677    shared_ptr<_Tp>&
4678>::type
4679shared_ptr<_Tp>::operator=(unique_ptr<_Yp, _Dp>&& __r)
4680{
4681    shared_ptr(_VSTD::move(__r)).swap(*this);
4682    return *this;
4683}
4684
4685#else  // _LIBCPP_HAS_NO_RVALUE_REFERENCES
4686
4687template<class _Tp>
4688template<class _Yp>
4689inline _LIBCPP_INLINE_VISIBILITY
4690typename enable_if
4691<
4692    !is_array<_Yp>::value &&
4693    is_convertible<_Yp*, _Tp*>::value,
4694    shared_ptr<_Tp>&
4695>::type
4696shared_ptr<_Tp>::operator=(auto_ptr<_Yp> __r)
4697{
4698    shared_ptr(__r).swap(*this);
4699    return *this;
4700}
4701
4702template<class _Tp>
4703template <class _Yp, class _Dp>
4704inline _LIBCPP_INLINE_VISIBILITY
4705typename enable_if
4706<
4707    !is_array<_Yp>::value &&
4708    is_convertible<typename unique_ptr<_Yp, _Dp>::pointer, _Tp*>::value,
4709    shared_ptr<_Tp>&
4710>::type
4711shared_ptr<_Tp>::operator=(unique_ptr<_Yp, _Dp> __r)
4712{
4713    shared_ptr(_VSTD::move(__r)).swap(*this);
4714    return *this;
4715}
4716
4717#endif  // _LIBCPP_HAS_NO_RVALUE_REFERENCES
4718
4719template<class _Tp>
4720inline
4721void
4722shared_ptr<_Tp>::swap(shared_ptr& __r) _NOEXCEPT
4723{
4724    _VSTD::swap(__ptr_, __r.__ptr_);
4725    _VSTD::swap(__cntrl_, __r.__cntrl_);
4726}
4727
4728template<class _Tp>
4729inline
4730void
4731shared_ptr<_Tp>::reset() _NOEXCEPT
4732{
4733    shared_ptr().swap(*this);
4734}
4735
4736template<class _Tp>
4737template<class _Yp>
4738inline
4739typename enable_if
4740<
4741    is_convertible<_Yp*, _Tp*>::value,
4742    void
4743>::type
4744shared_ptr<_Tp>::reset(_Yp* __p)
4745{
4746    shared_ptr(__p).swap(*this);
4747}
4748
4749template<class _Tp>
4750template<class _Yp, class _Dp>
4751inline
4752typename enable_if
4753<
4754    is_convertible<_Yp*, _Tp*>::value,
4755    void
4756>::type
4757shared_ptr<_Tp>::reset(_Yp* __p, _Dp __d)
4758{
4759    shared_ptr(__p, __d).swap(*this);
4760}
4761
4762template<class _Tp>
4763template<class _Yp, class _Dp, class _Alloc>
4764inline
4765typename enable_if
4766<
4767    is_convertible<_Yp*, _Tp*>::value,
4768    void
4769>::type
4770shared_ptr<_Tp>::reset(_Yp* __p, _Dp __d, _Alloc __a)
4771{
4772    shared_ptr(__p, __d, __a).swap(*this);
4773}
4774
4775#ifndef _LIBCPP_HAS_NO_VARIADICS
4776
4777template<class _Tp, class ..._Args>
4778inline _LIBCPP_INLINE_VISIBILITY
4779typename enable_if
4780<
4781    !is_array<_Tp>::value,
4782    shared_ptr<_Tp>
4783>::type
4784make_shared(_Args&& ...__args)
4785{
4786    return shared_ptr<_Tp>::make_shared(_VSTD::forward<_Args>(__args)...);
4787}
4788
4789template<class _Tp, class _Alloc, class ..._Args>
4790inline _LIBCPP_INLINE_VISIBILITY
4791typename enable_if
4792<
4793    !is_array<_Tp>::value,
4794    shared_ptr<_Tp>
4795>::type
4796allocate_shared(const _Alloc& __a, _Args&& ...__args)
4797{
4798    return shared_ptr<_Tp>::allocate_shared(__a, _VSTD::forward<_Args>(__args)...);
4799}
4800
4801#else  // _LIBCPP_HAS_NO_VARIADICS
4802
4803template<class _Tp>
4804inline _LIBCPP_INLINE_VISIBILITY
4805shared_ptr<_Tp>
4806make_shared()
4807{
4808    return shared_ptr<_Tp>::make_shared();
4809}
4810
4811template<class _Tp, class _A0>
4812inline _LIBCPP_INLINE_VISIBILITY
4813shared_ptr<_Tp>
4814make_shared(_A0& __a0)
4815{
4816    return shared_ptr<_Tp>::make_shared(__a0);
4817}
4818
4819template<class _Tp, class _A0, class _A1>
4820inline _LIBCPP_INLINE_VISIBILITY
4821shared_ptr<_Tp>
4822make_shared(_A0& __a0, _A1& __a1)
4823{
4824    return shared_ptr<_Tp>::make_shared(__a0, __a1);
4825}
4826
4827template<class _Tp, class _A0, class _A1, class _A2>
4828inline _LIBCPP_INLINE_VISIBILITY
4829shared_ptr<_Tp>
4830make_shared(_A0& __a0, _A1& __a1, _A2& __a2)
4831{
4832    return shared_ptr<_Tp>::make_shared(__a0, __a1, __a2);
4833}
4834
4835template<class _Tp, class _Alloc>
4836inline _LIBCPP_INLINE_VISIBILITY
4837shared_ptr<_Tp>
4838allocate_shared(const _Alloc& __a)
4839{
4840    return shared_ptr<_Tp>::allocate_shared(__a);
4841}
4842
4843template<class _Tp, class _Alloc, class _A0>
4844inline _LIBCPP_INLINE_VISIBILITY
4845shared_ptr<_Tp>
4846allocate_shared(const _Alloc& __a, _A0& __a0)
4847{
4848    return shared_ptr<_Tp>::allocate_shared(__a, __a0);
4849}
4850
4851template<class _Tp, class _Alloc, class _A0, class _A1>
4852inline _LIBCPP_INLINE_VISIBILITY
4853shared_ptr<_Tp>
4854allocate_shared(const _Alloc& __a, _A0& __a0, _A1& __a1)
4855{
4856    return shared_ptr<_Tp>::allocate_shared(__a, __a0, __a1);
4857}
4858
4859template<class _Tp, class _Alloc, class _A0, class _A1, class _A2>
4860inline _LIBCPP_INLINE_VISIBILITY
4861shared_ptr<_Tp>
4862allocate_shared(const _Alloc& __a, _A0& __a0, _A1& __a1, _A2& __a2)
4863{
4864    return shared_ptr<_Tp>::allocate_shared(__a, __a0, __a1, __a2);
4865}
4866
4867#endif  // _LIBCPP_HAS_NO_VARIADICS
4868
4869template<class _Tp, class _Up>
4870inline _LIBCPP_INLINE_VISIBILITY
4871bool
4872operator==(const shared_ptr<_Tp>& __x, const shared_ptr<_Up>& __y) _NOEXCEPT
4873{
4874    return __x.get() == __y.get();
4875}
4876
4877template<class _Tp, class _Up>
4878inline _LIBCPP_INLINE_VISIBILITY
4879bool
4880operator!=(const shared_ptr<_Tp>& __x, const shared_ptr<_Up>& __y) _NOEXCEPT
4881{
4882    return !(__x == __y);
4883}
4884
4885template<class _Tp, class _Up>
4886inline _LIBCPP_INLINE_VISIBILITY
4887bool
4888operator<(const shared_ptr<_Tp>& __x, const shared_ptr<_Up>& __y) _NOEXCEPT
4889{
4890    typedef typename common_type<_Tp*, _Up*>::type _Vp;
4891    return less<_Vp>()(__x.get(), __y.get());
4892}
4893
4894template<class _Tp, class _Up>
4895inline _LIBCPP_INLINE_VISIBILITY
4896bool
4897operator>(const shared_ptr<_Tp>& __x, const shared_ptr<_Up>& __y) _NOEXCEPT
4898{
4899    return __y < __x;
4900}
4901
4902template<class _Tp, class _Up>
4903inline _LIBCPP_INLINE_VISIBILITY
4904bool
4905operator<=(const shared_ptr<_Tp>& __x, const shared_ptr<_Up>& __y) _NOEXCEPT
4906{
4907    return !(__y < __x);
4908}
4909
4910template<class _Tp, class _Up>
4911inline _LIBCPP_INLINE_VISIBILITY
4912bool
4913operator>=(const shared_ptr<_Tp>& __x, const shared_ptr<_Up>& __y) _NOEXCEPT
4914{
4915    return !(__x < __y);
4916}
4917
4918template<class _Tp>
4919inline _LIBCPP_INLINE_VISIBILITY
4920bool
4921operator==(const shared_ptr<_Tp>& __x, nullptr_t) _NOEXCEPT
4922{
4923    return !__x;
4924}
4925
4926template<class _Tp>
4927inline _LIBCPP_INLINE_VISIBILITY
4928bool
4929operator==(nullptr_t, const shared_ptr<_Tp>& __x) _NOEXCEPT
4930{
4931    return !__x;
4932}
4933
4934template<class _Tp>
4935inline _LIBCPP_INLINE_VISIBILITY
4936bool
4937operator!=(const shared_ptr<_Tp>& __x, nullptr_t) _NOEXCEPT
4938{
4939    return static_cast<bool>(__x);
4940}
4941
4942template<class _Tp>
4943inline _LIBCPP_INLINE_VISIBILITY
4944bool
4945operator!=(nullptr_t, const shared_ptr<_Tp>& __x) _NOEXCEPT
4946{
4947    return static_cast<bool>(__x);
4948}
4949
4950template<class _Tp>
4951inline _LIBCPP_INLINE_VISIBILITY
4952bool
4953operator<(const shared_ptr<_Tp>& __x, nullptr_t) _NOEXCEPT
4954{
4955    return less<_Tp*>()(__x.get(), nullptr);
4956}
4957
4958template<class _Tp>
4959inline _LIBCPP_INLINE_VISIBILITY
4960bool
4961operator<(nullptr_t, const shared_ptr<_Tp>& __x) _NOEXCEPT
4962{
4963    return less<_Tp*>()(nullptr, __x.get());
4964}
4965
4966template<class _Tp>
4967inline _LIBCPP_INLINE_VISIBILITY
4968bool
4969operator>(const shared_ptr<_Tp>& __x, nullptr_t) _NOEXCEPT
4970{
4971    return nullptr < __x;
4972}
4973
4974template<class _Tp>
4975inline _LIBCPP_INLINE_VISIBILITY
4976bool
4977operator>(nullptr_t, const shared_ptr<_Tp>& __x) _NOEXCEPT
4978{
4979    return __x < nullptr;
4980}
4981
4982template<class _Tp>
4983inline _LIBCPP_INLINE_VISIBILITY
4984bool
4985operator<=(const shared_ptr<_Tp>& __x, nullptr_t) _NOEXCEPT
4986{
4987    return !(nullptr < __x);
4988}
4989
4990template<class _Tp>
4991inline _LIBCPP_INLINE_VISIBILITY
4992bool
4993operator<=(nullptr_t, const shared_ptr<_Tp>& __x) _NOEXCEPT
4994{
4995    return !(__x < nullptr);
4996}
4997
4998template<class _Tp>
4999inline _LIBCPP_INLINE_VISIBILITY
5000bool
5001operator>=(const shared_ptr<_Tp>& __x, nullptr_t) _NOEXCEPT
5002{
5003    return !(__x < nullptr);
5004}
5005
5006template<class _Tp>
5007inline _LIBCPP_INLINE_VISIBILITY
5008bool
5009operator>=(nullptr_t, const shared_ptr<_Tp>& __x) _NOEXCEPT
5010{
5011    return !(nullptr < __x);
5012}
5013
5014template<class _Tp>
5015inline _LIBCPP_INLINE_VISIBILITY
5016void
5017swap(shared_ptr<_Tp>& __x, shared_ptr<_Tp>& __y) _NOEXCEPT
5018{
5019    __x.swap(__y);
5020}
5021
5022template<class _Tp, class _Up>
5023inline _LIBCPP_INLINE_VISIBILITY
5024typename enable_if
5025<
5026    !is_array<_Tp>::value && !is_array<_Up>::value,
5027    shared_ptr<_Tp>
5028>::type
5029static_pointer_cast(const shared_ptr<_Up>& __r) _NOEXCEPT
5030{
5031    return shared_ptr<_Tp>(__r, static_cast<_Tp*>(__r.get()));
5032}
5033
5034template<class _Tp, class _Up>
5035inline _LIBCPP_INLINE_VISIBILITY
5036typename enable_if
5037<
5038    !is_array<_Tp>::value && !is_array<_Up>::value,
5039    shared_ptr<_Tp>
5040>::type
5041dynamic_pointer_cast(const shared_ptr<_Up>& __r) _NOEXCEPT
5042{
5043    _Tp* __p = dynamic_cast<_Tp*>(__r.get());
5044    return __p ? shared_ptr<_Tp>(__r, __p) : shared_ptr<_Tp>();
5045}
5046
5047template<class _Tp, class _Up>
5048typename enable_if
5049<
5050    is_array<_Tp>::value == is_array<_Up>::value,
5051    shared_ptr<_Tp>
5052>::type
5053const_pointer_cast(const shared_ptr<_Up>& __r) _NOEXCEPT
5054{
5055    typedef typename remove_extent<_Tp>::type _RTp;
5056    return shared_ptr<_Tp>(__r, const_cast<_RTp*>(__r.get()));
5057}
5058
5059#ifndef _LIBCPP_NO_RTTI
5060
5061template<class _Dp, class _Tp>
5062inline _LIBCPP_INLINE_VISIBILITY
5063_Dp*
5064get_deleter(const shared_ptr<_Tp>& __p) _NOEXCEPT
5065{
5066    return __p.template __get_deleter<_Dp>();
5067}
5068
5069#endif  // _LIBCPP_NO_RTTI
5070
5071template<class _Tp>
5072class _LIBCPP_TYPE_VIS_ONLY weak_ptr
5073{
5074public:
5075    typedef _Tp element_type;
5076private:
5077    element_type*        __ptr_;
5078    __shared_weak_count* __cntrl_;
5079
5080public:
5081    _LIBCPP_INLINE_VISIBILITY
5082    _LIBCPP_CONSTEXPR weak_ptr() _NOEXCEPT;
5083    template<class _Yp> _LIBCPP_INLINE_VISIBILITY weak_ptr(shared_ptr<_Yp> const& __r,
5084                   typename enable_if<is_convertible<_Yp*, _Tp*>::value, __nat*>::type = 0)
5085                        _NOEXCEPT;
5086    _LIBCPP_INLINE_VISIBILITY
5087    weak_ptr(weak_ptr const& __r) _NOEXCEPT;
5088    template<class _Yp> _LIBCPP_INLINE_VISIBILITY weak_ptr(weak_ptr<_Yp> const& __r,
5089                   typename enable_if<is_convertible<_Yp*, _Tp*>::value, __nat*>::type = 0)
5090                         _NOEXCEPT;
5091
5092#ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES
5093    _LIBCPP_INLINE_VISIBILITY
5094    weak_ptr(weak_ptr&& __r) _NOEXCEPT;
5095    template<class _Yp> _LIBCPP_INLINE_VISIBILITY weak_ptr(weak_ptr<_Yp>&& __r,
5096                   typename enable_if<is_convertible<_Yp*, _Tp*>::value, __nat*>::type = 0)
5097                         _NOEXCEPT;
5098#endif  // _LIBCPP_HAS_NO_RVALUE_REFERENCES
5099    ~weak_ptr();
5100
5101    _LIBCPP_INLINE_VISIBILITY
5102    weak_ptr& operator=(weak_ptr const& __r) _NOEXCEPT;
5103    template<class _Yp>
5104        typename enable_if
5105        <
5106            is_convertible<_Yp*, element_type*>::value,
5107            weak_ptr&
5108        >::type
5109        _LIBCPP_INLINE_VISIBILITY
5110        operator=(weak_ptr<_Yp> const& __r) _NOEXCEPT;
5111
5112#ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES
5113
5114    _LIBCPP_INLINE_VISIBILITY
5115    weak_ptr& operator=(weak_ptr&& __r) _NOEXCEPT;
5116    template<class _Yp>
5117        typename enable_if
5118        <
5119            is_convertible<_Yp*, element_type*>::value,
5120            weak_ptr&
5121        >::type
5122        _LIBCPP_INLINE_VISIBILITY
5123        operator=(weak_ptr<_Yp>&& __r) _NOEXCEPT;
5124
5125#endif  // _LIBCPP_HAS_NO_RVALUE_REFERENCES
5126
5127    template<class _Yp>
5128        typename enable_if
5129        <
5130            is_convertible<_Yp*, element_type*>::value,
5131            weak_ptr&
5132        >::type
5133        _LIBCPP_INLINE_VISIBILITY
5134        operator=(shared_ptr<_Yp> const& __r) _NOEXCEPT;
5135
5136    _LIBCPP_INLINE_VISIBILITY
5137    void swap(weak_ptr& __r) _NOEXCEPT;
5138    _LIBCPP_INLINE_VISIBILITY
5139    void reset() _NOEXCEPT;
5140
5141    _LIBCPP_INLINE_VISIBILITY
5142    long use_count() const _NOEXCEPT
5143        {return __cntrl_ ? __cntrl_->use_count() : 0;}
5144    _LIBCPP_INLINE_VISIBILITY
5145    bool expired() const _NOEXCEPT
5146        {return __cntrl_ == 0 || __cntrl_->use_count() == 0;}
5147    shared_ptr<_Tp> lock() const _NOEXCEPT;
5148    template<class _Up>
5149        _LIBCPP_INLINE_VISIBILITY
5150        bool owner_before(const shared_ptr<_Up>& __r) const
5151        {return __cntrl_ < __r.__cntrl_;}
5152    template<class _Up>
5153        _LIBCPP_INLINE_VISIBILITY
5154        bool owner_before(const weak_ptr<_Up>& __r) const
5155        {return __cntrl_ < __r.__cntrl_;}
5156
5157    template <class _Up> friend class _LIBCPP_TYPE_VIS_ONLY weak_ptr;
5158    template <class _Up> friend class _LIBCPP_TYPE_VIS_ONLY shared_ptr;
5159};
5160
5161template<class _Tp>
5162inline
5163_LIBCPP_CONSTEXPR
5164weak_ptr<_Tp>::weak_ptr() _NOEXCEPT
5165    : __ptr_(0),
5166      __cntrl_(0)
5167{
5168}
5169
5170template<class _Tp>
5171inline
5172weak_ptr<_Tp>::weak_ptr(weak_ptr const& __r) _NOEXCEPT
5173    : __ptr_(__r.__ptr_),
5174      __cntrl_(__r.__cntrl_)
5175{
5176    if (__cntrl_)
5177        __cntrl_->__add_weak();
5178}
5179
5180template<class _Tp>
5181template<class _Yp>
5182inline
5183weak_ptr<_Tp>::weak_ptr(shared_ptr<_Yp> const& __r,
5184                        typename enable_if<is_convertible<_Yp*, _Tp*>::value, __nat*>::type)
5185                         _NOEXCEPT
5186    : __ptr_(__r.__ptr_),
5187      __cntrl_(__r.__cntrl_)
5188{
5189    if (__cntrl_)
5190        __cntrl_->__add_weak();
5191}
5192
5193template<class _Tp>
5194template<class _Yp>
5195inline
5196weak_ptr<_Tp>::weak_ptr(weak_ptr<_Yp> const& __r,
5197                        typename enable_if<is_convertible<_Yp*, _Tp*>::value, __nat*>::type)
5198         _NOEXCEPT
5199    : __ptr_(__r.__ptr_),
5200      __cntrl_(__r.__cntrl_)
5201{
5202    if (__cntrl_)
5203        __cntrl_->__add_weak();
5204}
5205
5206#ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES
5207
5208template<class _Tp>
5209inline
5210weak_ptr<_Tp>::weak_ptr(weak_ptr&& __r) _NOEXCEPT
5211    : __ptr_(__r.__ptr_),
5212      __cntrl_(__r.__cntrl_)
5213{
5214    __r.__ptr_ = 0;
5215    __r.__cntrl_ = 0;
5216}
5217
5218template<class _Tp>
5219template<class _Yp>
5220inline
5221weak_ptr<_Tp>::weak_ptr(weak_ptr<_Yp>&& __r,
5222                        typename enable_if<is_convertible<_Yp*, _Tp*>::value, __nat*>::type)
5223         _NOEXCEPT
5224    : __ptr_(__r.__ptr_),
5225      __cntrl_(__r.__cntrl_)
5226{
5227    __r.__ptr_ = 0;
5228    __r.__cntrl_ = 0;
5229}
5230
5231#endif  // _LIBCPP_HAS_NO_RVALUE_REFERENCES
5232
5233template<class _Tp>
5234weak_ptr<_Tp>::~weak_ptr()
5235{
5236    if (__cntrl_)
5237        __cntrl_->__release_weak();
5238}
5239
5240template<class _Tp>
5241inline
5242weak_ptr<_Tp>&
5243weak_ptr<_Tp>::operator=(weak_ptr const& __r) _NOEXCEPT
5244{
5245    weak_ptr(__r).swap(*this);
5246    return *this;
5247}
5248
5249template<class _Tp>
5250template<class _Yp>
5251inline
5252typename enable_if
5253<
5254    is_convertible<_Yp*, _Tp*>::value,
5255    weak_ptr<_Tp>&
5256>::type
5257weak_ptr<_Tp>::operator=(weak_ptr<_Yp> const& __r) _NOEXCEPT
5258{
5259    weak_ptr(__r).swap(*this);
5260    return *this;
5261}
5262
5263#ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES
5264
5265template<class _Tp>
5266inline
5267weak_ptr<_Tp>&
5268weak_ptr<_Tp>::operator=(weak_ptr&& __r) _NOEXCEPT
5269{
5270    weak_ptr(_VSTD::move(__r)).swap(*this);
5271    return *this;
5272}
5273
5274template<class _Tp>
5275template<class _Yp>
5276inline
5277typename enable_if
5278<
5279    is_convertible<_Yp*, _Tp*>::value,
5280    weak_ptr<_Tp>&
5281>::type
5282weak_ptr<_Tp>::operator=(weak_ptr<_Yp>&& __r) _NOEXCEPT
5283{
5284    weak_ptr(_VSTD::move(__r)).swap(*this);
5285    return *this;
5286}
5287
5288#endif  // _LIBCPP_HAS_NO_RVALUE_REFERENCES
5289
5290template<class _Tp>
5291template<class _Yp>
5292inline
5293typename enable_if
5294<
5295    is_convertible<_Yp*, _Tp*>::value,
5296    weak_ptr<_Tp>&
5297>::type
5298weak_ptr<_Tp>::operator=(shared_ptr<_Yp> const& __r) _NOEXCEPT
5299{
5300    weak_ptr(__r).swap(*this);
5301    return *this;
5302}
5303
5304template<class _Tp>
5305inline
5306void
5307weak_ptr<_Tp>::swap(weak_ptr& __r) _NOEXCEPT
5308{
5309    _VSTD::swap(__ptr_, __r.__ptr_);
5310    _VSTD::swap(__cntrl_, __r.__cntrl_);
5311}
5312
5313template<class _Tp>
5314inline _LIBCPP_INLINE_VISIBILITY
5315void
5316swap(weak_ptr<_Tp>& __x, weak_ptr<_Tp>& __y) _NOEXCEPT
5317{
5318    __x.swap(__y);
5319}
5320
5321template<class _Tp>
5322inline
5323void
5324weak_ptr<_Tp>::reset() _NOEXCEPT
5325{
5326    weak_ptr().swap(*this);
5327}
5328
5329template<class _Tp>
5330template<class _Yp>
5331shared_ptr<_Tp>::shared_ptr(const weak_ptr<_Yp>& __r,
5332                            typename enable_if<is_convertible<_Yp*, _Tp*>::value, __nat>::type)
5333    : __ptr_(__r.__ptr_),
5334      __cntrl_(__r.__cntrl_ ? __r.__cntrl_->lock() : __r.__cntrl_)
5335{
5336    if (__cntrl_ == 0)
5337#ifndef _LIBCPP_NO_EXCEPTIONS
5338        throw bad_weak_ptr();
5339#else
5340        assert(!"bad_weak_ptr");
5341#endif
5342}
5343
5344template<class _Tp>
5345shared_ptr<_Tp>
5346weak_ptr<_Tp>::lock() const _NOEXCEPT
5347{
5348    shared_ptr<_Tp> __r;
5349    __r.__cntrl_ = __cntrl_ ? __cntrl_->lock() : __cntrl_;
5350    if (__r.__cntrl_)
5351        __r.__ptr_ = __ptr_;
5352    return __r;
5353}
5354
5355#if _LIBCPP_STD_VER > 14
5356template <class _Tp = void> struct owner_less;
5357#else
5358template <class _Tp> struct owner_less;
5359#endif
5360
5361template <class _Tp>
5362struct _LIBCPP_TYPE_VIS_ONLY owner_less<shared_ptr<_Tp> >
5363    : binary_function<shared_ptr<_Tp>, shared_ptr<_Tp>, bool>
5364{
5365    typedef bool result_type;
5366    _LIBCPP_INLINE_VISIBILITY
5367    bool operator()(shared_ptr<_Tp> const& __x, shared_ptr<_Tp> const& __y) const
5368        {return __x.owner_before(__y);}
5369    _LIBCPP_INLINE_VISIBILITY
5370    bool operator()(shared_ptr<_Tp> const& __x,   weak_ptr<_Tp> const& __y) const
5371        {return __x.owner_before(__y);}
5372    _LIBCPP_INLINE_VISIBILITY
5373    bool operator()(  weak_ptr<_Tp> const& __x, shared_ptr<_Tp> const& __y) const
5374        {return __x.owner_before(__y);}
5375};
5376
5377template <class _Tp>
5378struct _LIBCPP_TYPE_VIS_ONLY owner_less<weak_ptr<_Tp> >
5379    : binary_function<weak_ptr<_Tp>, weak_ptr<_Tp>, bool>
5380{
5381    typedef bool result_type;
5382    _LIBCPP_INLINE_VISIBILITY
5383    bool operator()(  weak_ptr<_Tp> const& __x,   weak_ptr<_Tp> const& __y) const
5384        {return __x.owner_before(__y);}
5385    _LIBCPP_INLINE_VISIBILITY
5386    bool operator()(shared_ptr<_Tp> const& __x,   weak_ptr<_Tp> const& __y) const
5387        {return __x.owner_before(__y);}
5388    _LIBCPP_INLINE_VISIBILITY
5389    bool operator()(  weak_ptr<_Tp> const& __x, shared_ptr<_Tp> const& __y) const
5390        {return __x.owner_before(__y);}
5391};
5392
5393#if _LIBCPP_STD_VER > 14
5394template <>
5395struct _LIBCPP_TYPE_VIS_ONLY owner_less<void>
5396{
5397    template <class _Tp, class _Up>
5398    _LIBCPP_INLINE_VISIBILITY
5399    bool operator()( shared_ptr<_Tp> const& __x, shared_ptr<_Up> const& __y) const
5400        {return __x.owner_before(__y);}
5401    template <class _Tp, class _Up>
5402    _LIBCPP_INLINE_VISIBILITY
5403    bool operator()( shared_ptr<_Tp> const& __x,  weak_ptr<_Up> const& __y) const
5404        {return __x.owner_before(__y);}
5405    template <class _Tp, class _Up>
5406    _LIBCPP_INLINE_VISIBILITY
5407    bool operator()(   weak_ptr<_Tp> const& __x, shared_ptr<_Up> const& __y) const
5408        {return __x.owner_before(__y);}
5409    template <class _Tp, class _Up>
5410    _LIBCPP_INLINE_VISIBILITY
5411    bool operator()(   weak_ptr<_Tp> const& __x,   weak_ptr<_Up> const& __y) const
5412        {return __x.owner_before(__y);}
5413    typedef void is_transparent;
5414};
5415#endif
5416
5417template<class _Tp>
5418class _LIBCPP_TYPE_VIS_ONLY enable_shared_from_this
5419{
5420    mutable weak_ptr<_Tp> __weak_this_;
5421protected:
5422    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR
5423    enable_shared_from_this() _NOEXCEPT {}
5424    _LIBCPP_INLINE_VISIBILITY
5425    enable_shared_from_this(enable_shared_from_this const&) _NOEXCEPT {}
5426    _LIBCPP_INLINE_VISIBILITY
5427    enable_shared_from_this& operator=(enable_shared_from_this const&) _NOEXCEPT
5428        {return *this;}
5429    _LIBCPP_INLINE_VISIBILITY
5430    ~enable_shared_from_this() {}
5431public:
5432    _LIBCPP_INLINE_VISIBILITY
5433    shared_ptr<_Tp> shared_from_this()
5434        {return shared_ptr<_Tp>(__weak_this_);}
5435    _LIBCPP_INLINE_VISIBILITY
5436    shared_ptr<_Tp const> shared_from_this() const
5437        {return shared_ptr<const _Tp>(__weak_this_);}
5438
5439    template <class _Up> friend class shared_ptr;
5440};
5441
5442template <class _Tp>
5443struct _LIBCPP_TYPE_VIS_ONLY hash<shared_ptr<_Tp> >
5444{
5445    typedef shared_ptr<_Tp>      argument_type;
5446    typedef size_t               result_type;
5447    _LIBCPP_INLINE_VISIBILITY
5448    result_type operator()(const argument_type& __ptr) const _NOEXCEPT
5449    {
5450        return hash<_Tp*>()(__ptr.get());
5451    }
5452};
5453
5454template<class _CharT, class _Traits, class _Yp>
5455inline _LIBCPP_INLINE_VISIBILITY
5456basic_ostream<_CharT, _Traits>&
5457operator<<(basic_ostream<_CharT, _Traits>& __os, shared_ptr<_Yp> const& __p);
5458
5459// TODO(EricWF): Enable this for both Clang and GCC. Currently it is only
5460// enabled with clang.
5461#if defined(_LIBCPP_HAS_C_ATOMIC_IMP) && !defined(_LIBCPP_HAS_NO_THREADS)
5462
5463class _LIBCPP_TYPE_VIS __sp_mut
5464{
5465    void* __lx;
5466public:
5467    void lock() _NOEXCEPT;
5468    void unlock() _NOEXCEPT;
5469
5470private:
5471    _LIBCPP_CONSTEXPR __sp_mut(void*) _NOEXCEPT;
5472    __sp_mut(const __sp_mut&);
5473    __sp_mut& operator=(const __sp_mut&);
5474
5475    friend _LIBCPP_FUNC_VIS __sp_mut& __get_sp_mut(const void*);
5476};
5477
5478_LIBCPP_FUNC_VIS __sp_mut& __get_sp_mut(const void*);
5479
5480template <class _Tp>
5481inline _LIBCPP_INLINE_VISIBILITY
5482bool
5483atomic_is_lock_free(const shared_ptr<_Tp>*)
5484{
5485    return false;
5486}
5487
5488template <class _Tp>
5489shared_ptr<_Tp>
5490atomic_load(const shared_ptr<_Tp>* __p)
5491{
5492    __sp_mut& __m = __get_sp_mut(__p);
5493    __m.lock();
5494    shared_ptr<_Tp> __q = *__p;
5495    __m.unlock();
5496    return __q;
5497}
5498
5499template <class _Tp>
5500inline _LIBCPP_INLINE_VISIBILITY
5501shared_ptr<_Tp>
5502atomic_load_explicit(const shared_ptr<_Tp>* __p, memory_order)
5503{
5504    return atomic_load(__p);
5505}
5506
5507template <class _Tp>
5508void
5509atomic_store(shared_ptr<_Tp>* __p, shared_ptr<_Tp> __r)
5510{
5511    __sp_mut& __m = __get_sp_mut(__p);
5512    __m.lock();
5513    __p->swap(__r);
5514    __m.unlock();
5515}
5516
5517template <class _Tp>
5518inline _LIBCPP_INLINE_VISIBILITY
5519void
5520atomic_store_explicit(shared_ptr<_Tp>* __p, shared_ptr<_Tp> __r, memory_order)
5521{
5522    atomic_store(__p, __r);
5523}
5524
5525template <class _Tp>
5526shared_ptr<_Tp>
5527atomic_exchange(shared_ptr<_Tp>* __p, shared_ptr<_Tp> __r)
5528{
5529    __sp_mut& __m = __get_sp_mut(__p);
5530    __m.lock();
5531    __p->swap(__r);
5532    __m.unlock();
5533    return __r;
5534}
5535
5536template <class _Tp>
5537inline _LIBCPP_INLINE_VISIBILITY
5538shared_ptr<_Tp>
5539atomic_exchange_explicit(shared_ptr<_Tp>* __p, shared_ptr<_Tp> __r, memory_order)
5540{
5541    return atomic_exchange(__p, __r);
5542}
5543
5544template <class _Tp>
5545bool
5546atomic_compare_exchange_strong(shared_ptr<_Tp>* __p, shared_ptr<_Tp>* __v, shared_ptr<_Tp> __w)
5547{
5548    __sp_mut& __m = __get_sp_mut(__p);
5549    __m.lock();
5550    if (__p->__owner_equivalent(*__v))
5551    {
5552        *__p = __w;
5553        __m.unlock();
5554        return true;
5555    }
5556    *__v = *__p;
5557    __m.unlock();
5558    return false;
5559}
5560
5561template <class _Tp>
5562inline _LIBCPP_INLINE_VISIBILITY
5563bool
5564atomic_compare_exchange_weak(shared_ptr<_Tp>* __p, shared_ptr<_Tp>* __v, shared_ptr<_Tp> __w)
5565{
5566    return atomic_compare_exchange_strong(__p, __v, __w);
5567}
5568
5569template <class _Tp>
5570inline _LIBCPP_INLINE_VISIBILITY
5571bool
5572atomic_compare_exchange_strong_explicit(shared_ptr<_Tp>* __p, shared_ptr<_Tp>* __v,
5573                                        shared_ptr<_Tp> __w, memory_order, memory_order)
5574{
5575    return atomic_compare_exchange_strong(__p, __v, __w);
5576}
5577
5578template <class _Tp>
5579inline _LIBCPP_INLINE_VISIBILITY
5580bool
5581atomic_compare_exchange_weak_explicit(shared_ptr<_Tp>* __p, shared_ptr<_Tp>* __v,
5582                                      shared_ptr<_Tp> __w, memory_order, memory_order)
5583{
5584    return atomic_compare_exchange_weak(__p, __v, __w);
5585}
5586
5587#endif  // defined(_LIBCPP_HAS_C_ATOMIC_IMP) && !defined(_LIBCPP_HAS_NO_THREADS)
5588
5589//enum class
5590struct _LIBCPP_TYPE_VIS pointer_safety
5591{
5592    enum __lx
5593    {
5594        relaxed,
5595        preferred,
5596        strict
5597    };
5598
5599    __lx __v_;
5600
5601    _LIBCPP_INLINE_VISIBILITY
5602    pointer_safety(__lx __v) : __v_(__v) {}
5603    _LIBCPP_INLINE_VISIBILITY
5604    operator int() const {return __v_;}
5605};
5606
5607_LIBCPP_FUNC_VIS void declare_reachable(void* __p);
5608_LIBCPP_FUNC_VIS void declare_no_pointers(char* __p, size_t __n);
5609_LIBCPP_FUNC_VIS void undeclare_no_pointers(char* __p, size_t __n);
5610_LIBCPP_FUNC_VIS pointer_safety get_pointer_safety() _NOEXCEPT;
5611_LIBCPP_FUNC_VIS void* __undeclare_reachable(void* __p);
5612
5613template <class _Tp>
5614inline _LIBCPP_INLINE_VISIBILITY
5615_Tp*
5616undeclare_reachable(_Tp* __p)
5617{
5618    return static_cast<_Tp*>(__undeclare_reachable(__p));
5619}
5620
5621_LIBCPP_FUNC_VIS void* align(size_t __align, size_t __sz, void*& __ptr, size_t& __space);
5622
5623// --- Helper for container swap --
5624template <typename _Alloc>
5625_LIBCPP_INLINE_VISIBILITY
5626void __swap_allocator(_Alloc & __a1, _Alloc & __a2)
5627#if _LIBCPP_STD_VER >= 14
5628    _NOEXCEPT
5629#else
5630    _NOEXCEPT_(__is_nothrow_swappable<_Alloc>::value)
5631#endif
5632{
5633    __swap_allocator(__a1, __a2,
5634      integral_constant<bool, _VSTD::allocator_traits<_Alloc>::propagate_on_container_swap::value>());
5635}
5636
5637template <typename _Alloc>
5638_LIBCPP_INLINE_VISIBILITY
5639void __swap_allocator(_Alloc & __a1, _Alloc & __a2, true_type)
5640#if _LIBCPP_STD_VER >= 14
5641    _NOEXCEPT
5642#else
5643    _NOEXCEPT_(__is_nothrow_swappable<_Alloc>::value)
5644#endif
5645{
5646    using _VSTD::swap;
5647    swap(__a1, __a2);
5648}
5649
5650template <typename _Alloc>
5651_LIBCPP_INLINE_VISIBILITY
5652void __swap_allocator(_Alloc &, _Alloc &, false_type) _NOEXCEPT {}
5653
5654template <typename _Alloc, typename _Traits=allocator_traits<_Alloc> >
5655struct __noexcept_move_assign_container : public integral_constant<bool,
5656    _Traits::propagate_on_container_move_assignment::value
5657#if _LIBCPP_STD_VER > 14
5658        || _Traits::is_always_equal::value
5659#else
5660        && is_nothrow_move_assignable<_Alloc>::value
5661#endif
5662    > {};
5663
5664_LIBCPP_END_NAMESPACE_STD
5665
5666#endif  // _LIBCPP_MEMORY
5667