xref: /freebsd-12.1/contrib/libc++/include/memory (revision 2b375b4e)
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    typedef weak_ptr<T> weak_type; // C++17
365
366    // constructors:
367    constexpr shared_ptr() noexcept;
368    template<class Y> explicit shared_ptr(Y* p);
369    template<class Y, class D> shared_ptr(Y* p, D d);
370    template<class Y, class D, class A> shared_ptr(Y* p, D d, A a);
371    template <class D> shared_ptr(nullptr_t p, D d);
372    template <class D, class A> shared_ptr(nullptr_t p, D d, A a);
373    template<class Y> shared_ptr(const shared_ptr<Y>& r, T *p) noexcept;
374    shared_ptr(const shared_ptr& r) noexcept;
375    template<class Y> shared_ptr(const shared_ptr<Y>& r) noexcept;
376    shared_ptr(shared_ptr&& r) noexcept;
377    template<class Y> shared_ptr(shared_ptr<Y>&& r) noexcept;
378    template<class Y> explicit shared_ptr(const weak_ptr<Y>& r);
379    template<class Y> shared_ptr(auto_ptr<Y>&& r);
380    template <class Y, class D> shared_ptr(unique_ptr<Y, D>&& r);
381    shared_ptr(nullptr_t) : shared_ptr() { }
382
383    // destructor:
384    ~shared_ptr();
385
386    // assignment:
387    shared_ptr& operator=(const shared_ptr& r) noexcept;
388    template<class Y> shared_ptr& operator=(const shared_ptr<Y>& r) noexcept;
389    shared_ptr& operator=(shared_ptr&& r) noexcept;
390    template<class Y> shared_ptr& operator=(shared_ptr<Y>&& r);
391    template<class Y> shared_ptr& operator=(auto_ptr<Y>&& r);
392    template <class Y, class D> shared_ptr& operator=(unique_ptr<Y, D>&& r);
393
394    // modifiers:
395    void swap(shared_ptr& r) noexcept;
396    void reset() noexcept;
397    template<class Y> void reset(Y* p);
398    template<class Y, class D> void reset(Y* p, D d);
399    template<class Y, class D, class A> void reset(Y* p, D d, A a);
400
401    // observers:
402    T* get() const noexcept;
403    T& operator*() const noexcept;
404    T* operator->() const noexcept;
405    long use_count() const noexcept;
406    bool unique() const noexcept;
407    explicit operator bool() const noexcept;
408    template<class U> bool owner_before(shared_ptr<U> const& b) const;
409    template<class U> bool owner_before(weak_ptr<U> const& b) const;
410};
411
412// shared_ptr comparisons:
413template<class T, class U>
414    bool operator==(shared_ptr<T> const& a, shared_ptr<U> const& b) noexcept;
415template<class T, class U>
416    bool operator!=(shared_ptr<T> const& a, shared_ptr<U> const& b) noexcept;
417template<class T, class U>
418    bool operator<(shared_ptr<T> const& a, shared_ptr<U> const& b) noexcept;
419template<class T, class U>
420    bool operator>(shared_ptr<T> const& a, shared_ptr<U> const& b) noexcept;
421template<class T, class U>
422    bool operator<=(shared_ptr<T> const& a, shared_ptr<U> const& b) noexcept;
423template<class T, class U>
424    bool operator>=(shared_ptr<T> const& a, shared_ptr<U> const& b) noexcept;
425
426template <class T>
427    bool operator==(const shared_ptr<T>& x, nullptr_t) noexcept;
428template <class T>
429    bool operator==(nullptr_t, const shared_ptr<T>& y) noexcept;
430template <class T>
431    bool operator!=(const shared_ptr<T>& x, nullptr_t) noexcept;
432template <class T>
433    bool operator!=(nullptr_t, const shared_ptr<T>& y) noexcept;
434template <class T>
435    bool operator<(const shared_ptr<T>& x, nullptr_t) noexcept;
436template <class T>
437bool operator<(nullptr_t, const shared_ptr<T>& y) noexcept;
438template <class T>
439    bool operator<=(const shared_ptr<T>& x, nullptr_t) noexcept;
440template <class T>
441    bool operator<=(nullptr_t, const shared_ptr<T>& y) noexcept;
442template <class T>
443    bool operator>(const shared_ptr<T>& x, nullptr_t) noexcept;
444template <class T>
445    bool operator>(nullptr_t, const shared_ptr<T>& y) noexcept;
446template <class T>
447    bool operator>=(const shared_ptr<T>& x, nullptr_t) noexcept;
448template <class T>
449    bool operator>=(nullptr_t, const shared_ptr<T>& y) noexcept;
450
451// shared_ptr specialized algorithms:
452template<class T> void swap(shared_ptr<T>& a, shared_ptr<T>& b) noexcept;
453
454// shared_ptr casts:
455template<class T, class U>
456    shared_ptr<T> static_pointer_cast(shared_ptr<U> const& r) noexcept;
457template<class T, class U>
458    shared_ptr<T> dynamic_pointer_cast(shared_ptr<U> const& r) noexcept;
459template<class T, class U>
460    shared_ptr<T> const_pointer_cast(shared_ptr<U> const& r) noexcept;
461
462// shared_ptr I/O:
463template<class E, class T, class Y>
464    basic_ostream<E, T>& operator<< (basic_ostream<E, T>& os, shared_ptr<Y> const& p);
465
466// shared_ptr get_deleter:
467template<class D, class T> D* get_deleter(shared_ptr<T> const& p) noexcept;
468
469template<class T, class... Args>
470    shared_ptr<T> make_shared(Args&&... args);
471template<class T, class A, class... Args>
472    shared_ptr<T> allocate_shared(const A& a, Args&&... args);
473
474template<class T>
475class weak_ptr
476{
477public:
478    typedef T element_type;
479
480    // constructors
481    constexpr weak_ptr() noexcept;
482    template<class Y> weak_ptr(shared_ptr<Y> const& r) noexcept;
483    weak_ptr(weak_ptr const& r) noexcept;
484    template<class Y> weak_ptr(weak_ptr<Y> const& r) noexcept;
485    weak_ptr(weak_ptr&& r) noexcept;                      // C++14
486    template<class Y> weak_ptr(weak_ptr<Y>&& r) noexcept; // C++14
487
488    // destructor
489    ~weak_ptr();
490
491    // assignment
492    weak_ptr& operator=(weak_ptr const& r) noexcept;
493    template<class Y> weak_ptr& operator=(weak_ptr<Y> const& r) noexcept;
494    template<class Y> weak_ptr& operator=(shared_ptr<Y> const& r) noexcept;
495    weak_ptr& operator=(weak_ptr&& r) noexcept;                      // C++14
496    template<class Y> weak_ptr& operator=(weak_ptr<Y>&& r) noexcept; // C++14
497
498    // modifiers
499    void swap(weak_ptr& r) noexcept;
500    void reset() noexcept;
501
502    // observers
503    long use_count() const noexcept;
504    bool expired() const noexcept;
505    shared_ptr<T> lock() const noexcept;
506    template<class U> bool owner_before(shared_ptr<U> const& b) const;
507    template<class U> bool owner_before(weak_ptr<U> const& b) const;
508};
509
510// weak_ptr specialized algorithms:
511template<class T> void swap(weak_ptr<T>& a, weak_ptr<T>& b) noexcept;
512
513// class owner_less:
514template<class T> struct owner_less;
515
516template<class T>
517struct owner_less<shared_ptr<T>>
518    : binary_function<shared_ptr<T>, shared_ptr<T>, bool>
519{
520    typedef bool result_type;
521    bool operator()(shared_ptr<T> const&, shared_ptr<T> const&) const;
522    bool operator()(shared_ptr<T> const&, weak_ptr<T> const&) const;
523    bool operator()(weak_ptr<T> const&, shared_ptr<T> const&) const;
524};
525
526template<class T>
527struct owner_less<weak_ptr<T>>
528    : binary_function<weak_ptr<T>, weak_ptr<T>, bool>
529{
530    typedef bool result_type;
531    bool operator()(weak_ptr<T> const&, weak_ptr<T> const&) const;
532    bool operator()(shared_ptr<T> const&, weak_ptr<T> const&) const;
533    bool operator()(weak_ptr<T> const&, shared_ptr<T> const&) const;
534};
535
536template<class T>
537class enable_shared_from_this
538{
539protected:
540    constexpr enable_shared_from_this() noexcept;
541    enable_shared_from_this(enable_shared_from_this const&) noexcept;
542    enable_shared_from_this& operator=(enable_shared_from_this const&) noexcept;
543    ~enable_shared_from_this();
544public:
545    shared_ptr<T> shared_from_this();
546    shared_ptr<T const> shared_from_this() const;
547};
548
549template<class T>
550    bool atomic_is_lock_free(const shared_ptr<T>* p);
551template<class T>
552    shared_ptr<T> atomic_load(const shared_ptr<T>* p);
553template<class T>
554    shared_ptr<T> atomic_load_explicit(const shared_ptr<T>* p, memory_order mo);
555template<class T>
556    void atomic_store(shared_ptr<T>* p, shared_ptr<T> r);
557template<class T>
558    void atomic_store_explicit(shared_ptr<T>* p, shared_ptr<T> r, memory_order mo);
559template<class T>
560    shared_ptr<T> atomic_exchange(shared_ptr<T>* p, shared_ptr<T> r);
561template<class T>
562    shared_ptr<T>
563    atomic_exchange_explicit(shared_ptr<T>* p, shared_ptr<T> r, memory_order mo);
564template<class T>
565    bool
566    atomic_compare_exchange_weak(shared_ptr<T>* p, shared_ptr<T>* v, shared_ptr<T> w);
567template<class T>
568    bool
569    atomic_compare_exchange_strong( shared_ptr<T>* p, shared_ptr<T>* v, shared_ptr<T> w);
570template<class T>
571    bool
572    atomic_compare_exchange_weak_explicit(shared_ptr<T>* p, shared_ptr<T>* v,
573                                          shared_ptr<T> w, memory_order success,
574                                          memory_order failure);
575template<class T>
576    bool
577    atomic_compare_exchange_strong_explicit(shared_ptr<T>* p, shared_ptr<T>* v,
578                                            shared_ptr<T> w, memory_order success,
579                                            memory_order failure);
580// Hash support
581template <class T> struct hash;
582template <class T, class D> struct hash<unique_ptr<T, D> >;
583template <class T> struct hash<shared_ptr<T> >;
584
585// Pointer safety
586enum class pointer_safety { relaxed, preferred, strict };
587void declare_reachable(void *p);
588template <class T> T *undeclare_reachable(T *p);
589void declare_no_pointers(char *p, size_t n);
590void undeclare_no_pointers(char *p, size_t n);
591pointer_safety get_pointer_safety() noexcept;
592
593void* align(size_t alignment, size_t size, void*& ptr, size_t& space);
594
595}  // std
596
597*/
598
599#include <__config>
600#include <type_traits>
601#include <typeinfo>
602#include <cstddef>
603#include <cstdint>
604#include <new>
605#include <utility>
606#include <limits>
607#include <iterator>
608#include <__functional_base>
609#include <iosfwd>
610#include <tuple>
611#include <stdexcept>
612#include <cstring>
613#if defined(_LIBCPP_NO_EXCEPTIONS)
614    #include <cassert>
615#endif
616
617#if !defined(_LIBCPP_HAS_NO_ATOMIC_HEADER)
618#  include <atomic>
619#endif
620
621#include <__undef_min_max>
622#include <__undef___deallocate>
623
624#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
625#pragma GCC system_header
626#endif
627
628_LIBCPP_BEGIN_NAMESPACE_STD
629
630template <class _ValueType>
631inline _LIBCPP_ALWAYS_INLINE
632_ValueType __libcpp_relaxed_load(_ValueType const* __value) {
633#if !defined(_LIBCPP_HAS_NO_THREADS) && \
634    defined(__ATOMIC_RELAXED) &&        \
635    (__has_builtin(__atomic_load_n) || _GNUC_VER >= 407)
636    return __atomic_load_n(__value, __ATOMIC_RELAXED);
637#else
638    return *__value;
639#endif
640}
641
642// addressof moved to <__functional_base>
643
644template <class _Tp> class allocator;
645
646template <>
647class _LIBCPP_TYPE_VIS_ONLY allocator<void>
648{
649public:
650    typedef void*             pointer;
651    typedef const void*       const_pointer;
652    typedef void              value_type;
653
654    template <class _Up> struct rebind {typedef allocator<_Up> other;};
655};
656
657template <>
658class _LIBCPP_TYPE_VIS_ONLY allocator<const void>
659{
660public:
661    typedef const void*       pointer;
662    typedef const void*       const_pointer;
663    typedef const void        value_type;
664
665    template <class _Up> struct rebind {typedef allocator<_Up> other;};
666};
667
668// pointer_traits
669
670template <class _Tp>
671struct __has_element_type
672{
673private:
674    struct __two {char __lx; char __lxx;};
675    template <class _Up> static __two __test(...);
676    template <class _Up> static char __test(typename _Up::element_type* = 0);
677public:
678    static const bool value = sizeof(__test<_Tp>(0)) == 1;
679};
680
681template <class _Ptr, bool = __has_element_type<_Ptr>::value>
682struct __pointer_traits_element_type;
683
684template <class _Ptr>
685struct __pointer_traits_element_type<_Ptr, true>
686{
687    typedef typename _Ptr::element_type type;
688};
689
690#ifndef _LIBCPP_HAS_NO_VARIADICS
691
692template <template <class, class...> class _Sp, class _Tp, class ..._Args>
693struct __pointer_traits_element_type<_Sp<_Tp, _Args...>, true>
694{
695    typedef typename _Sp<_Tp, _Args...>::element_type type;
696};
697
698template <template <class, class...> class _Sp, class _Tp, class ..._Args>
699struct __pointer_traits_element_type<_Sp<_Tp, _Args...>, false>
700{
701    typedef _Tp type;
702};
703
704#else  // _LIBCPP_HAS_NO_VARIADICS
705
706template <template <class> class _Sp, class _Tp>
707struct __pointer_traits_element_type<_Sp<_Tp>, true>
708{
709    typedef typename _Sp<_Tp>::element_type type;
710};
711
712template <template <class> class _Sp, class _Tp>
713struct __pointer_traits_element_type<_Sp<_Tp>, false>
714{
715    typedef _Tp type;
716};
717
718template <template <class, class> class _Sp, class _Tp, class _A0>
719struct __pointer_traits_element_type<_Sp<_Tp, _A0>, true>
720{
721    typedef typename _Sp<_Tp, _A0>::element_type type;
722};
723
724template <template <class, class> class _Sp, class _Tp, class _A0>
725struct __pointer_traits_element_type<_Sp<_Tp, _A0>, false>
726{
727    typedef _Tp type;
728};
729
730template <template <class, class, class> class _Sp, class _Tp, class _A0, class _A1>
731struct __pointer_traits_element_type<_Sp<_Tp, _A0, _A1>, true>
732{
733    typedef typename _Sp<_Tp, _A0, _A1>::element_type type;
734};
735
736template <template <class, class, class> class _Sp, class _Tp, class _A0, class _A1>
737struct __pointer_traits_element_type<_Sp<_Tp, _A0, _A1>, false>
738{
739    typedef _Tp type;
740};
741
742template <template <class, class, class, class> class _Sp, class _Tp, class _A0,
743                                                           class _A1, class _A2>
744struct __pointer_traits_element_type<_Sp<_Tp, _A0, _A1, _A2>, true>
745{
746    typedef typename _Sp<_Tp, _A0, _A1, _A2>::element_type type;
747};
748
749template <template <class, class, class, class> class _Sp, class _Tp, class _A0,
750                                                           class _A1, class _A2>
751struct __pointer_traits_element_type<_Sp<_Tp, _A0, _A1, _A2>, false>
752{
753    typedef _Tp type;
754};
755
756#endif  // _LIBCPP_HAS_NO_VARIADICS
757
758template <class _Tp>
759struct __has_difference_type
760{
761private:
762    struct __two {char __lx; char __lxx;};
763    template <class _Up> static __two __test(...);
764    template <class _Up> static char __test(typename _Up::difference_type* = 0);
765public:
766    static const bool value = sizeof(__test<_Tp>(0)) == 1;
767};
768
769template <class _Ptr, bool = __has_difference_type<_Ptr>::value>
770struct __pointer_traits_difference_type
771{
772    typedef ptrdiff_t type;
773};
774
775template <class _Ptr>
776struct __pointer_traits_difference_type<_Ptr, true>
777{
778    typedef typename _Ptr::difference_type type;
779};
780
781template <class _Tp, class _Up>
782struct __has_rebind
783{
784private:
785    struct __two {char __lx; char __lxx;};
786    template <class _Xp> static __two __test(...);
787    template <class _Xp> static char __test(typename _Xp::template rebind<_Up>* = 0);
788public:
789    static const bool value = sizeof(__test<_Tp>(0)) == 1;
790};
791
792template <class _Tp, class _Up, bool = __has_rebind<_Tp, _Up>::value>
793struct __pointer_traits_rebind
794{
795#ifndef _LIBCPP_HAS_NO_TEMPLATE_ALIASES
796    typedef typename _Tp::template rebind<_Up> type;
797#else
798    typedef typename _Tp::template rebind<_Up>::other type;
799#endif
800};
801
802#ifndef _LIBCPP_HAS_NO_VARIADICS
803
804template <template <class, class...> class _Sp, class _Tp, class ..._Args, class _Up>
805struct __pointer_traits_rebind<_Sp<_Tp, _Args...>, _Up, true>
806{
807#ifndef _LIBCPP_HAS_NO_TEMPLATE_ALIASES
808    typedef typename _Sp<_Tp, _Args...>::template rebind<_Up> type;
809#else
810    typedef typename _Sp<_Tp, _Args...>::template rebind<_Up>::other type;
811#endif
812};
813
814template <template <class, class...> class _Sp, class _Tp, class ..._Args, class _Up>
815struct __pointer_traits_rebind<_Sp<_Tp, _Args...>, _Up, false>
816{
817    typedef _Sp<_Up, _Args...> type;
818};
819
820#else  // _LIBCPP_HAS_NO_VARIADICS
821
822template <template <class> class _Sp, class _Tp, class _Up>
823struct __pointer_traits_rebind<_Sp<_Tp>, _Up, true>
824{
825#ifndef _LIBCPP_HAS_NO_TEMPLATE_ALIASES
826    typedef typename _Sp<_Tp>::template rebind<_Up> type;
827#else
828    typedef typename _Sp<_Tp>::template rebind<_Up>::other type;
829#endif
830};
831
832template <template <class> class _Sp, class _Tp, class _Up>
833struct __pointer_traits_rebind<_Sp<_Tp>, _Up, false>
834{
835    typedef _Sp<_Up> type;
836};
837
838template <template <class, class> class _Sp, class _Tp, class _A0, class _Up>
839struct __pointer_traits_rebind<_Sp<_Tp, _A0>, _Up, true>
840{
841#ifndef _LIBCPP_HAS_NO_TEMPLATE_ALIASES
842    typedef typename _Sp<_Tp, _A0>::template rebind<_Up> type;
843#else
844    typedef typename _Sp<_Tp, _A0>::template rebind<_Up>::other type;
845#endif
846};
847
848template <template <class, class> class _Sp, class _Tp, class _A0, class _Up>
849struct __pointer_traits_rebind<_Sp<_Tp, _A0>, _Up, false>
850{
851    typedef _Sp<_Up, _A0> type;
852};
853
854template <template <class, class, class> class _Sp, class _Tp, class _A0,
855                                         class _A1, class _Up>
856struct __pointer_traits_rebind<_Sp<_Tp, _A0, _A1>, _Up, true>
857{
858#ifndef _LIBCPP_HAS_NO_TEMPLATE_ALIASES
859    typedef typename _Sp<_Tp, _A0, _A1>::template rebind<_Up> type;
860#else
861    typedef typename _Sp<_Tp, _A0, _A1>::template rebind<_Up>::other type;
862#endif
863};
864
865template <template <class, class, class> class _Sp, class _Tp, class _A0,
866                                         class _A1, class _Up>
867struct __pointer_traits_rebind<_Sp<_Tp, _A0, _A1>, _Up, false>
868{
869    typedef _Sp<_Up, _A0, _A1> type;
870};
871
872template <template <class, class, class, class> class _Sp, class _Tp, class _A0,
873                                                class _A1, class _A2, class _Up>
874struct __pointer_traits_rebind<_Sp<_Tp, _A0, _A1, _A2>, _Up, true>
875{
876#ifndef _LIBCPP_HAS_NO_TEMPLATE_ALIASES
877    typedef typename _Sp<_Tp, _A0, _A1, _A2>::template rebind<_Up> type;
878#else
879    typedef typename _Sp<_Tp, _A0, _A1, _A2>::template rebind<_Up>::other type;
880#endif
881};
882
883template <template <class, class, class, class> class _Sp, class _Tp, class _A0,
884                                                class _A1, class _A2, class _Up>
885struct __pointer_traits_rebind<_Sp<_Tp, _A0, _A1, _A2>, _Up, false>
886{
887    typedef _Sp<_Up, _A0, _A1, _A2> type;
888};
889
890#endif  // _LIBCPP_HAS_NO_VARIADICS
891
892template <class _Ptr>
893struct _LIBCPP_TYPE_VIS_ONLY pointer_traits
894{
895    typedef _Ptr                                                     pointer;
896    typedef typename __pointer_traits_element_type<pointer>::type    element_type;
897    typedef typename __pointer_traits_difference_type<pointer>::type difference_type;
898
899#ifndef _LIBCPP_HAS_NO_TEMPLATE_ALIASES
900    template <class _Up> using rebind = typename __pointer_traits_rebind<pointer, _Up>::type;
901#else
902    template <class _Up> struct rebind
903        {typedef typename __pointer_traits_rebind<pointer, _Up>::type other;};
904#endif  // _LIBCPP_HAS_NO_TEMPLATE_ALIASES
905
906private:
907    struct __nat {};
908public:
909    _LIBCPP_INLINE_VISIBILITY
910    static pointer pointer_to(typename conditional<is_void<element_type>::value,
911                                           __nat, element_type>::type& __r)
912        {return pointer::pointer_to(__r);}
913};
914
915template <class _Tp>
916struct _LIBCPP_TYPE_VIS_ONLY pointer_traits<_Tp*>
917{
918    typedef _Tp*      pointer;
919    typedef _Tp       element_type;
920    typedef ptrdiff_t difference_type;
921
922#ifndef _LIBCPP_HAS_NO_TEMPLATE_ALIASES
923    template <class _Up> using rebind = _Up*;
924#else
925    template <class _Up> struct rebind {typedef _Up* other;};
926#endif
927
928private:
929    struct __nat {};
930public:
931    _LIBCPP_INLINE_VISIBILITY
932    static pointer pointer_to(typename conditional<is_void<element_type>::value,
933                                      __nat, element_type>::type& __r) _NOEXCEPT
934        {return _VSTD::addressof(__r);}
935};
936
937template <class _From, class _To>
938struct __rebind_pointer {
939#ifndef _LIBCPP_HAS_NO_TEMPLATE_ALIASES
940    typedef typename pointer_traits<_From>::template rebind<_To>        type;
941#else
942    typedef typename pointer_traits<_From>::template rebind<_To>::other type;
943#endif
944};
945
946// allocator_traits
947
948namespace __has_pointer_type_imp
949{
950    template <class _Up> static __two __test(...);
951    template <class _Up> static char __test(typename _Up::pointer* = 0);
952}
953
954template <class _Tp>
955struct __has_pointer_type
956    : public integral_constant<bool, sizeof(__has_pointer_type_imp::__test<_Tp>(0)) == 1>
957{
958};
959
960namespace __pointer_type_imp
961{
962
963template <class _Tp, class _Dp, bool = __has_pointer_type<_Dp>::value>
964struct __pointer_type
965{
966    typedef typename _Dp::pointer type;
967};
968
969template <class _Tp, class _Dp>
970struct __pointer_type<_Tp, _Dp, false>
971{
972    typedef _Tp* type;
973};
974
975}  // __pointer_type_imp
976
977template <class _Tp, class _Dp>
978struct __pointer_type
979{
980    typedef typename __pointer_type_imp::__pointer_type<_Tp, typename remove_reference<_Dp>::type>::type type;
981};
982
983template <class _Tp>
984struct __has_const_pointer
985{
986private:
987    struct __two {char __lx; char __lxx;};
988    template <class _Up> static __two __test(...);
989    template <class _Up> static char __test(typename _Up::const_pointer* = 0);
990public:
991    static const bool value = sizeof(__test<_Tp>(0)) == 1;
992};
993
994template <class _Tp, class _Ptr, class _Alloc, bool = __has_const_pointer<_Alloc>::value>
995struct __const_pointer
996{
997    typedef typename _Alloc::const_pointer type;
998};
999
1000template <class _Tp, class _Ptr, class _Alloc>
1001struct __const_pointer<_Tp, _Ptr, _Alloc, false>
1002{
1003#ifndef _LIBCPP_HAS_NO_TEMPLATE_ALIASES
1004    typedef typename pointer_traits<_Ptr>::template rebind<const _Tp> type;
1005#else
1006    typedef typename pointer_traits<_Ptr>::template rebind<const _Tp>::other type;
1007#endif
1008};
1009
1010template <class _Tp>
1011struct __has_void_pointer
1012{
1013private:
1014    struct __two {char __lx; char __lxx;};
1015    template <class _Up> static __two __test(...);
1016    template <class _Up> static char __test(typename _Up::void_pointer* = 0);
1017public:
1018    static const bool value = sizeof(__test<_Tp>(0)) == 1;
1019};
1020
1021template <class _Ptr, class _Alloc, bool = __has_void_pointer<_Alloc>::value>
1022struct __void_pointer
1023{
1024    typedef typename _Alloc::void_pointer type;
1025};
1026
1027template <class _Ptr, class _Alloc>
1028struct __void_pointer<_Ptr, _Alloc, false>
1029{
1030#ifndef _LIBCPP_HAS_NO_TEMPLATE_ALIASES
1031    typedef typename pointer_traits<_Ptr>::template rebind<void> type;
1032#else
1033    typedef typename pointer_traits<_Ptr>::template rebind<void>::other type;
1034#endif
1035};
1036
1037template <class _Tp>
1038struct __has_const_void_pointer
1039{
1040private:
1041    struct __two {char __lx; char __lxx;};
1042    template <class _Up> static __two __test(...);
1043    template <class _Up> static char __test(typename _Up::const_void_pointer* = 0);
1044public:
1045    static const bool value = sizeof(__test<_Tp>(0)) == 1;
1046};
1047
1048template <class _Ptr, class _Alloc, bool = __has_const_void_pointer<_Alloc>::value>
1049struct __const_void_pointer
1050{
1051    typedef typename _Alloc::const_void_pointer type;
1052};
1053
1054template <class _Ptr, class _Alloc>
1055struct __const_void_pointer<_Ptr, _Alloc, false>
1056{
1057#ifndef _LIBCPP_HAS_NO_TEMPLATE_ALIASES
1058    typedef typename pointer_traits<_Ptr>::template rebind<const void> type;
1059#else
1060    typedef typename pointer_traits<_Ptr>::template rebind<const void>::other type;
1061#endif
1062};
1063
1064template <class _Tp>
1065inline _LIBCPP_INLINE_VISIBILITY
1066_Tp*
1067__to_raw_pointer(_Tp* __p) _NOEXCEPT
1068{
1069    return __p;
1070}
1071
1072template <class _Pointer>
1073inline _LIBCPP_INLINE_VISIBILITY
1074typename pointer_traits<_Pointer>::element_type*
1075__to_raw_pointer(_Pointer __p) _NOEXCEPT
1076{
1077    return _VSTD::__to_raw_pointer(__p.operator->());
1078}
1079
1080template <class _Tp>
1081struct __has_size_type
1082{
1083private:
1084    struct __two {char __lx; char __lxx;};
1085    template <class _Up> static __two __test(...);
1086    template <class _Up> static char __test(typename _Up::size_type* = 0);
1087public:
1088    static const bool value = sizeof(__test<_Tp>(0)) == 1;
1089};
1090
1091template <class _Alloc, class _DiffType, bool = __has_size_type<_Alloc>::value>
1092struct __size_type
1093{
1094    typedef typename make_unsigned<_DiffType>::type type;
1095};
1096
1097template <class _Alloc, class _DiffType>
1098struct __size_type<_Alloc, _DiffType, true>
1099{
1100    typedef typename _Alloc::size_type type;
1101};
1102
1103template <class _Tp>
1104struct __has_propagate_on_container_copy_assignment
1105{
1106private:
1107    struct __two {char __lx; char __lxx;};
1108    template <class _Up> static __two __test(...);
1109    template <class _Up> static char __test(typename _Up::propagate_on_container_copy_assignment* = 0);
1110public:
1111    static const bool value = sizeof(__test<_Tp>(0)) == 1;
1112};
1113
1114template <class _Alloc, bool = __has_propagate_on_container_copy_assignment<_Alloc>::value>
1115struct __propagate_on_container_copy_assignment
1116{
1117    typedef false_type type;
1118};
1119
1120template <class _Alloc>
1121struct __propagate_on_container_copy_assignment<_Alloc, true>
1122{
1123    typedef typename _Alloc::propagate_on_container_copy_assignment type;
1124};
1125
1126template <class _Tp>
1127struct __has_propagate_on_container_move_assignment
1128{
1129private:
1130    struct __two {char __lx; char __lxx;};
1131    template <class _Up> static __two __test(...);
1132    template <class _Up> static char __test(typename _Up::propagate_on_container_move_assignment* = 0);
1133public:
1134    static const bool value = sizeof(__test<_Tp>(0)) == 1;
1135};
1136
1137template <class _Alloc, bool = __has_propagate_on_container_move_assignment<_Alloc>::value>
1138struct __propagate_on_container_move_assignment
1139{
1140    typedef false_type type;
1141};
1142
1143template <class _Alloc>
1144struct __propagate_on_container_move_assignment<_Alloc, true>
1145{
1146    typedef typename _Alloc::propagate_on_container_move_assignment type;
1147};
1148
1149template <class _Tp>
1150struct __has_propagate_on_container_swap
1151{
1152private:
1153    struct __two {char __lx; char __lxx;};
1154    template <class _Up> static __two __test(...);
1155    template <class _Up> static char __test(typename _Up::propagate_on_container_swap* = 0);
1156public:
1157    static const bool value = sizeof(__test<_Tp>(0)) == 1;
1158};
1159
1160template <class _Alloc, bool = __has_propagate_on_container_swap<_Alloc>::value>
1161struct __propagate_on_container_swap
1162{
1163    typedef false_type type;
1164};
1165
1166template <class _Alloc>
1167struct __propagate_on_container_swap<_Alloc, true>
1168{
1169    typedef typename _Alloc::propagate_on_container_swap type;
1170};
1171
1172template <class _Tp>
1173struct __has_is_always_equal
1174{
1175private:
1176    struct __two {char __lx; char __lxx;};
1177    template <class _Up> static __two __test(...);
1178    template <class _Up> static char __test(typename _Up::is_always_equal* = 0);
1179public:
1180    static const bool value = sizeof(__test<_Tp>(0)) == 1;
1181};
1182
1183template <class _Alloc, bool = __has_is_always_equal<_Alloc>::value>
1184struct __is_always_equal
1185{
1186    typedef typename _VSTD::is_empty<_Alloc>::type type;
1187};
1188
1189template <class _Alloc>
1190struct __is_always_equal<_Alloc, true>
1191{
1192    typedef typename _Alloc::is_always_equal type;
1193};
1194
1195template <class _Tp, class _Up, bool = __has_rebind<_Tp, _Up>::value>
1196struct __has_rebind_other
1197{
1198private:
1199    struct __two {char __lx; char __lxx;};
1200    template <class _Xp> static __two __test(...);
1201    template <class _Xp> static char __test(typename _Xp::template rebind<_Up>::other* = 0);
1202public:
1203    static const bool value = sizeof(__test<_Tp>(0)) == 1;
1204};
1205
1206template <class _Tp, class _Up>
1207struct __has_rebind_other<_Tp, _Up, false>
1208{
1209    static const bool value = false;
1210};
1211
1212template <class _Tp, class _Up, bool = __has_rebind_other<_Tp, _Up>::value>
1213struct __allocator_traits_rebind
1214{
1215    typedef typename _Tp::template rebind<_Up>::other type;
1216};
1217
1218#ifndef _LIBCPP_HAS_NO_VARIADICS
1219
1220template <template <class, class...> class _Alloc, class _Tp, class ..._Args, class _Up>
1221struct __allocator_traits_rebind<_Alloc<_Tp, _Args...>, _Up, true>
1222{
1223    typedef typename _Alloc<_Tp, _Args...>::template rebind<_Up>::other type;
1224};
1225
1226template <template <class, class...> class _Alloc, class _Tp, class ..._Args, class _Up>
1227struct __allocator_traits_rebind<_Alloc<_Tp, _Args...>, _Up, false>
1228{
1229    typedef _Alloc<_Up, _Args...> type;
1230};
1231
1232#else  // _LIBCPP_HAS_NO_VARIADICS
1233
1234template <template <class> class _Alloc, class _Tp, class _Up>
1235struct __allocator_traits_rebind<_Alloc<_Tp>, _Up, true>
1236{
1237    typedef typename _Alloc<_Tp>::template rebind<_Up>::other type;
1238};
1239
1240template <template <class> class _Alloc, class _Tp, class _Up>
1241struct __allocator_traits_rebind<_Alloc<_Tp>, _Up, false>
1242{
1243    typedef _Alloc<_Up> type;
1244};
1245
1246template <template <class, class> class _Alloc, class _Tp, class _A0, class _Up>
1247struct __allocator_traits_rebind<_Alloc<_Tp, _A0>, _Up, true>
1248{
1249    typedef typename _Alloc<_Tp, _A0>::template rebind<_Up>::other type;
1250};
1251
1252template <template <class, class> class _Alloc, class _Tp, class _A0, class _Up>
1253struct __allocator_traits_rebind<_Alloc<_Tp, _A0>, _Up, false>
1254{
1255    typedef _Alloc<_Up, _A0> type;
1256};
1257
1258template <template <class, class, class> class _Alloc, class _Tp, class _A0,
1259                                         class _A1, class _Up>
1260struct __allocator_traits_rebind<_Alloc<_Tp, _A0, _A1>, _Up, true>
1261{
1262    typedef typename _Alloc<_Tp, _A0, _A1>::template rebind<_Up>::other type;
1263};
1264
1265template <template <class, class, class> class _Alloc, class _Tp, class _A0,
1266                                         class _A1, class _Up>
1267struct __allocator_traits_rebind<_Alloc<_Tp, _A0, _A1>, _Up, false>
1268{
1269    typedef _Alloc<_Up, _A0, _A1> type;
1270};
1271
1272template <template <class, class, class, class> class _Alloc, class _Tp, class _A0,
1273                                                class _A1, class _A2, class _Up>
1274struct __allocator_traits_rebind<_Alloc<_Tp, _A0, _A1, _A2>, _Up, true>
1275{
1276    typedef typename _Alloc<_Tp, _A0, _A1, _A2>::template rebind<_Up>::other type;
1277};
1278
1279template <template <class, class, class, class> class _Alloc, class _Tp, class _A0,
1280                                                class _A1, class _A2, class _Up>
1281struct __allocator_traits_rebind<_Alloc<_Tp, _A0, _A1, _A2>, _Up, false>
1282{
1283    typedef _Alloc<_Up, _A0, _A1, _A2> type;
1284};
1285
1286#endif  // _LIBCPP_HAS_NO_VARIADICS
1287
1288#ifndef _LIBCPP_HAS_NO_ADVANCED_SFINAE
1289
1290template <class _Alloc, class _SizeType, class _ConstVoidPtr>
1291auto
1292__has_allocate_hint_test(_Alloc&& __a, _SizeType&& __sz, _ConstVoidPtr&& __p)
1293    -> decltype(__a.allocate(__sz, __p), true_type());
1294
1295template <class _Alloc, class _SizeType, class _ConstVoidPtr>
1296auto
1297__has_allocate_hint_test(const _Alloc& __a, _SizeType&& __sz, _ConstVoidPtr&& __p)
1298    -> false_type;
1299
1300template <class _Alloc, class _SizeType, class _ConstVoidPtr>
1301struct __has_allocate_hint
1302    : integral_constant<bool,
1303        is_same<
1304            decltype(__has_allocate_hint_test(declval<_Alloc>(),
1305                                          declval<_SizeType>(),
1306                                          declval<_ConstVoidPtr>())),
1307            true_type>::value>
1308{
1309};
1310
1311#else  // _LIBCPP_HAS_NO_ADVANCED_SFINAE
1312
1313template <class _Alloc, class _SizeType, class _ConstVoidPtr>
1314struct __has_allocate_hint
1315    : true_type
1316{
1317};
1318
1319#endif  // _LIBCPP_HAS_NO_ADVANCED_SFINAE
1320
1321#if !defined(_LIBCPP_HAS_NO_ADVANCED_SFINAE) && !defined(_LIBCPP_HAS_NO_VARIADICS)
1322
1323template <class _Alloc, class _Tp, class ..._Args>
1324decltype(_VSTD::declval<_Alloc>().construct(_VSTD::declval<_Tp*>(),
1325                                           _VSTD::declval<_Args>()...),
1326                                           true_type())
1327__has_construct_test(_Alloc&& __a, _Tp* __p, _Args&& ...__args);
1328
1329template <class _Alloc, class _Pointer, class ..._Args>
1330false_type
1331__has_construct_test(const _Alloc& __a, _Pointer&& __p, _Args&& ...__args);
1332
1333template <class _Alloc, class _Pointer, class ..._Args>
1334struct __has_construct
1335    : integral_constant<bool,
1336        is_same<
1337            decltype(__has_construct_test(declval<_Alloc>(),
1338                                          declval<_Pointer>(),
1339                                          declval<_Args>()...)),
1340            true_type>::value>
1341{
1342};
1343
1344template <class _Alloc, class _Pointer>
1345auto
1346__has_destroy_test(_Alloc&& __a, _Pointer&& __p)
1347    -> decltype(__a.destroy(__p), true_type());
1348
1349template <class _Alloc, class _Pointer>
1350auto
1351__has_destroy_test(const _Alloc& __a, _Pointer&& __p)
1352    -> false_type;
1353
1354template <class _Alloc, class _Pointer>
1355struct __has_destroy
1356    : integral_constant<bool,
1357        is_same<
1358            decltype(__has_destroy_test(declval<_Alloc>(),
1359                                        declval<_Pointer>())),
1360            true_type>::value>
1361{
1362};
1363
1364template <class _Alloc>
1365auto
1366__has_max_size_test(_Alloc&& __a)
1367    -> decltype(__a.max_size(), true_type());
1368
1369template <class _Alloc>
1370auto
1371__has_max_size_test(const volatile _Alloc& __a)
1372    -> false_type;
1373
1374template <class _Alloc>
1375struct __has_max_size
1376    : integral_constant<bool,
1377        is_same<
1378            decltype(__has_max_size_test(declval<_Alloc&>())),
1379            true_type>::value>
1380{
1381};
1382
1383template <class _Alloc>
1384auto
1385__has_select_on_container_copy_construction_test(_Alloc&& __a)
1386    -> decltype(__a.select_on_container_copy_construction(), true_type());
1387
1388template <class _Alloc>
1389auto
1390__has_select_on_container_copy_construction_test(const volatile _Alloc& __a)
1391    -> false_type;
1392
1393template <class _Alloc>
1394struct __has_select_on_container_copy_construction
1395    : integral_constant<bool,
1396        is_same<
1397            decltype(__has_select_on_container_copy_construction_test(declval<_Alloc&>())),
1398            true_type>::value>
1399{
1400};
1401
1402#else  // _LIBCPP_HAS_NO_ADVANCED_SFINAE
1403
1404#ifndef _LIBCPP_HAS_NO_VARIADICS
1405
1406template <class _Alloc, class _Pointer, class ..._Args>
1407struct __has_construct
1408    : false_type
1409{
1410};
1411
1412#else  // _LIBCPP_HAS_NO_VARIADICS
1413
1414template <class _Alloc, class _Pointer, class _Args>
1415struct __has_construct
1416    : false_type
1417{
1418};
1419
1420#endif  // _LIBCPP_HAS_NO_VARIADICS
1421
1422template <class _Alloc, class _Pointer>
1423struct __has_destroy
1424    : false_type
1425{
1426};
1427
1428template <class _Alloc>
1429struct __has_max_size
1430    : true_type
1431{
1432};
1433
1434template <class _Alloc>
1435struct __has_select_on_container_copy_construction
1436    : false_type
1437{
1438};
1439
1440#endif  // _LIBCPP_HAS_NO_ADVANCED_SFINAE
1441
1442template <class _Alloc, class _Ptr, bool = __has_difference_type<_Alloc>::value>
1443struct __alloc_traits_difference_type
1444{
1445    typedef typename pointer_traits<_Ptr>::difference_type type;
1446};
1447
1448template <class _Alloc, class _Ptr>
1449struct __alloc_traits_difference_type<_Alloc, _Ptr, true>
1450{
1451    typedef typename _Alloc::difference_type type;
1452};
1453
1454template <class _Alloc>
1455struct _LIBCPP_TYPE_VIS_ONLY allocator_traits
1456{
1457    typedef _Alloc                              allocator_type;
1458    typedef typename allocator_type::value_type value_type;
1459
1460    typedef typename __pointer_type<value_type, allocator_type>::type pointer;
1461    typedef typename __const_pointer<value_type, pointer, allocator_type>::type const_pointer;
1462    typedef typename __void_pointer<pointer, allocator_type>::type void_pointer;
1463    typedef typename __const_void_pointer<pointer, allocator_type>::type const_void_pointer;
1464
1465    typedef typename __alloc_traits_difference_type<allocator_type, pointer>::type difference_type;
1466    typedef typename __size_type<allocator_type, difference_type>::type size_type;
1467
1468    typedef typename __propagate_on_container_copy_assignment<allocator_type>::type
1469                     propagate_on_container_copy_assignment;
1470    typedef typename __propagate_on_container_move_assignment<allocator_type>::type
1471                     propagate_on_container_move_assignment;
1472    typedef typename __propagate_on_container_swap<allocator_type>::type
1473                     propagate_on_container_swap;
1474    typedef typename __is_always_equal<allocator_type>::type
1475                     is_always_equal;
1476
1477#ifndef _LIBCPP_HAS_NO_TEMPLATE_ALIASES
1478    template <class _Tp> using rebind_alloc =
1479                  typename __allocator_traits_rebind<allocator_type, _Tp>::type;
1480    template <class _Tp> using rebind_traits = allocator_traits<rebind_alloc<_Tp>>;
1481#else  // _LIBCPP_HAS_NO_TEMPLATE_ALIASES
1482    template <class _Tp> struct rebind_alloc
1483        {typedef typename __allocator_traits_rebind<allocator_type, _Tp>::type other;};
1484    template <class _Tp> struct rebind_traits
1485        {typedef allocator_traits<typename rebind_alloc<_Tp>::other> other;};
1486#endif  // _LIBCPP_HAS_NO_TEMPLATE_ALIASES
1487
1488    _LIBCPP_INLINE_VISIBILITY
1489    static pointer allocate(allocator_type& __a, size_type __n)
1490        {return __a.allocate(__n);}
1491    _LIBCPP_INLINE_VISIBILITY
1492    static pointer allocate(allocator_type& __a, size_type __n, const_void_pointer __hint)
1493        {return allocate(__a, __n, __hint,
1494            __has_allocate_hint<allocator_type, size_type, const_void_pointer>());}
1495
1496    _LIBCPP_INLINE_VISIBILITY
1497    static void deallocate(allocator_type& __a, pointer __p, size_type __n) _NOEXCEPT
1498        {__a.deallocate(__p, __n);}
1499
1500#ifndef _LIBCPP_HAS_NO_VARIADICS
1501    template <class _Tp, class... _Args>
1502        _LIBCPP_INLINE_VISIBILITY
1503        static void construct(allocator_type& __a, _Tp* __p, _Args&&... __args)
1504            {__construct(__has_construct<allocator_type, _Tp*, _Args...>(),
1505                         __a, __p, _VSTD::forward<_Args>(__args)...);}
1506#else  // _LIBCPP_HAS_NO_VARIADICS
1507    template <class _Tp>
1508        _LIBCPP_INLINE_VISIBILITY
1509        static void construct(allocator_type& __a, _Tp* __p)
1510            {
1511                ::new ((void*)__p) _Tp();
1512            }
1513    template <class _Tp, class _A0>
1514        _LIBCPP_INLINE_VISIBILITY
1515        static void construct(allocator_type& __a, _Tp* __p, const _A0& __a0)
1516            {
1517                ::new ((void*)__p) _Tp(__a0);
1518            }
1519    template <class _Tp, class _A0, class _A1>
1520        _LIBCPP_INLINE_VISIBILITY
1521        static void construct(allocator_type& __a, _Tp* __p, const _A0& __a0,
1522                              const _A1& __a1)
1523            {
1524                ::new ((void*)__p) _Tp(__a0, __a1);
1525            }
1526    template <class _Tp, class _A0, class _A1, class _A2>
1527        _LIBCPP_INLINE_VISIBILITY
1528        static void construct(allocator_type& __a, _Tp* __p, const _A0& __a0,
1529                              const _A1& __a1, const _A2& __a2)
1530            {
1531                ::new ((void*)__p) _Tp(__a0, __a1, __a2);
1532            }
1533#endif  // _LIBCPP_HAS_NO_VARIADICS
1534
1535    template <class _Tp>
1536        _LIBCPP_INLINE_VISIBILITY
1537        static void destroy(allocator_type& __a, _Tp* __p)
1538            {__destroy(__has_destroy<allocator_type, _Tp*>(), __a, __p);}
1539
1540    _LIBCPP_INLINE_VISIBILITY
1541    static size_type max_size(const allocator_type& __a) _NOEXCEPT
1542        {return __max_size(__has_max_size<const allocator_type>(), __a);}
1543
1544    _LIBCPP_INLINE_VISIBILITY
1545    static allocator_type
1546        select_on_container_copy_construction(const allocator_type& __a)
1547            {return select_on_container_copy_construction(
1548                __has_select_on_container_copy_construction<const allocator_type>(),
1549                __a);}
1550
1551    template <class _Ptr>
1552        _LIBCPP_INLINE_VISIBILITY
1553        static
1554        void
1555        __construct_forward(allocator_type& __a, _Ptr __begin1, _Ptr __end1, _Ptr& __begin2)
1556        {
1557            for (; __begin1 != __end1; ++__begin1, ++__begin2)
1558                construct(__a, _VSTD::__to_raw_pointer(__begin2), _VSTD::move_if_noexcept(*__begin1));
1559        }
1560
1561    template <class _Tp>
1562        _LIBCPP_INLINE_VISIBILITY
1563        static
1564        typename enable_if
1565        <
1566            (is_same<allocator_type, allocator<_Tp> >::value
1567                || !__has_construct<allocator_type, _Tp*, _Tp>::value) &&
1568             is_trivially_move_constructible<_Tp>::value,
1569            void
1570        >::type
1571        __construct_forward(allocator_type& __a, _Tp* __begin1, _Tp* __end1, _Tp*& __begin2)
1572        {
1573            ptrdiff_t _Np = __end1 - __begin1;
1574            if (_Np > 0)
1575            {
1576                _VSTD::memcpy(__begin2, __begin1, _Np * sizeof(_Tp));
1577                __begin2 += _Np;
1578            }
1579        }
1580
1581    template <class _Iter, class _Ptr>
1582        _LIBCPP_INLINE_VISIBILITY
1583        static
1584        void
1585        __construct_range_forward(allocator_type& __a, _Iter __begin1, _Iter __end1, _Ptr& __begin2)
1586        {
1587            for (; __begin1 != __end1; ++__begin1, (void) ++__begin2)
1588                construct(__a, _VSTD::__to_raw_pointer(__begin2), *__begin1);
1589        }
1590
1591    template <class _Tp>
1592        _LIBCPP_INLINE_VISIBILITY
1593        static
1594        typename enable_if
1595        <
1596            (is_same<allocator_type, allocator<_Tp> >::value
1597                || !__has_construct<allocator_type, _Tp*, _Tp>::value) &&
1598             is_trivially_move_constructible<_Tp>::value,
1599            void
1600        >::type
1601        __construct_range_forward(allocator_type& __a, _Tp* __begin1, _Tp* __end1, _Tp*& __begin2)
1602        {
1603            typedef typename remove_const<_Tp>::type _Vp;
1604            ptrdiff_t _Np = __end1 - __begin1;
1605            if (_Np > 0)
1606            {
1607                _VSTD::memcpy(const_cast<_Vp*>(__begin2), __begin1, _Np * sizeof(_Tp));
1608                __begin2 += _Np;
1609            }
1610        }
1611
1612    template <class _Ptr>
1613        _LIBCPP_INLINE_VISIBILITY
1614        static
1615        void
1616        __construct_backward(allocator_type& __a, _Ptr __begin1, _Ptr __end1, _Ptr& __end2)
1617        {
1618            while (__end1 != __begin1)
1619            {
1620                construct(__a, _VSTD::__to_raw_pointer(__end2-1), _VSTD::move_if_noexcept(*--__end1));
1621                --__end2;
1622            }
1623        }
1624
1625    template <class _Tp>
1626        _LIBCPP_INLINE_VISIBILITY
1627        static
1628        typename enable_if
1629        <
1630            (is_same<allocator_type, allocator<_Tp> >::value
1631                || !__has_construct<allocator_type, _Tp*, _Tp>::value) &&
1632             is_trivially_move_constructible<_Tp>::value,
1633            void
1634        >::type
1635        __construct_backward(allocator_type& __a, _Tp* __begin1, _Tp* __end1, _Tp*& __end2)
1636        {
1637            ptrdiff_t _Np = __end1 - __begin1;
1638            __end2 -= _Np;
1639            if (_Np > 0)
1640                _VSTD::memcpy(__end2, __begin1, _Np * sizeof(_Tp));
1641        }
1642
1643private:
1644
1645    _LIBCPP_INLINE_VISIBILITY
1646    static pointer allocate(allocator_type& __a, size_type __n,
1647        const_void_pointer __hint, true_type)
1648        {return __a.allocate(__n, __hint);}
1649    _LIBCPP_INLINE_VISIBILITY
1650    static pointer allocate(allocator_type& __a, size_type __n,
1651        const_void_pointer, false_type)
1652        {return __a.allocate(__n);}
1653
1654#ifndef _LIBCPP_HAS_NO_VARIADICS
1655    template <class _Tp, class... _Args>
1656        _LIBCPP_INLINE_VISIBILITY
1657        static void __construct(true_type, allocator_type& __a, _Tp* __p, _Args&&... __args)
1658            {__a.construct(__p, _VSTD::forward<_Args>(__args)...);}
1659    template <class _Tp, class... _Args>
1660        _LIBCPP_INLINE_VISIBILITY
1661        static void __construct(false_type, allocator_type&, _Tp* __p, _Args&&... __args)
1662            {
1663                ::new ((void*)__p) _Tp(_VSTD::forward<_Args>(__args)...);
1664            }
1665#endif  // _LIBCPP_HAS_NO_VARIADICS
1666
1667    template <class _Tp>
1668        _LIBCPP_INLINE_VISIBILITY
1669        static void __destroy(true_type, allocator_type& __a, _Tp* __p)
1670            {__a.destroy(__p);}
1671    template <class _Tp>
1672        _LIBCPP_INLINE_VISIBILITY
1673        static void __destroy(false_type, allocator_type&, _Tp* __p)
1674            {
1675                __p->~_Tp();
1676            }
1677
1678    _LIBCPP_INLINE_VISIBILITY
1679    static size_type __max_size(true_type, const allocator_type& __a)
1680            {return __a.max_size();}
1681    _LIBCPP_INLINE_VISIBILITY
1682    static size_type __max_size(false_type, const allocator_type&)
1683            {return numeric_limits<size_type>::max() / sizeof(value_type);}
1684
1685    _LIBCPP_INLINE_VISIBILITY
1686    static allocator_type
1687        select_on_container_copy_construction(true_type, const allocator_type& __a)
1688            {return __a.select_on_container_copy_construction();}
1689    _LIBCPP_INLINE_VISIBILITY
1690    static allocator_type
1691        select_on_container_copy_construction(false_type, const allocator_type& __a)
1692            {return __a;}
1693};
1694
1695template <class _Traits, class _Tp>
1696struct __rebind_alloc_helper
1697{
1698#ifndef _LIBCPP_HAS_NO_TEMPLATE_ALIASES
1699    typedef typename _Traits::template rebind_alloc<_Tp>        type;
1700#else
1701    typedef typename _Traits::template rebind_alloc<_Tp>::other type;
1702#endif
1703};
1704
1705// allocator
1706
1707template <class _Tp>
1708class _LIBCPP_TYPE_VIS_ONLY allocator
1709{
1710public:
1711    typedef size_t            size_type;
1712    typedef ptrdiff_t         difference_type;
1713    typedef _Tp*              pointer;
1714    typedef const _Tp*        const_pointer;
1715    typedef _Tp&              reference;
1716    typedef const _Tp&        const_reference;
1717    typedef _Tp               value_type;
1718
1719    typedef true_type propagate_on_container_move_assignment;
1720    typedef true_type is_always_equal;
1721
1722    template <class _Up> struct rebind {typedef allocator<_Up> other;};
1723
1724    _LIBCPP_INLINE_VISIBILITY allocator() _NOEXCEPT {}
1725    template <class _Up> _LIBCPP_INLINE_VISIBILITY allocator(const allocator<_Up>&) _NOEXCEPT {}
1726    _LIBCPP_INLINE_VISIBILITY pointer address(reference __x) const _NOEXCEPT
1727        {return _VSTD::addressof(__x);}
1728    _LIBCPP_INLINE_VISIBILITY const_pointer address(const_reference __x) const _NOEXCEPT
1729        {return _VSTD::addressof(__x);}
1730    _LIBCPP_INLINE_VISIBILITY pointer allocate(size_type __n, allocator<void>::const_pointer = 0)
1731        {
1732        if (__n > max_size())
1733            __libcpp_throw(length_error("allocator<T>::allocate(size_t n)"
1734                                      " 'n' exceeds maximum supported size"));
1735        return static_cast<pointer>(_VSTD::__allocate(__n * sizeof(_Tp)));
1736        }
1737    _LIBCPP_INLINE_VISIBILITY void deallocate(pointer __p, size_type) _NOEXCEPT
1738        {_VSTD::__deallocate((void*)__p);}
1739    _LIBCPP_INLINE_VISIBILITY size_type max_size() const _NOEXCEPT
1740        {return size_type(~0) / sizeof(_Tp);}
1741#if !defined(_LIBCPP_HAS_NO_RVALUE_REFERENCES) && !defined(_LIBCPP_HAS_NO_VARIADICS)
1742    template <class _Up, class... _Args>
1743        _LIBCPP_INLINE_VISIBILITY
1744        void
1745        construct(_Up* __p, _Args&&... __args)
1746        {
1747            ::new((void*)__p) _Up(_VSTD::forward<_Args>(__args)...);
1748        }
1749#else  // !defined(_LIBCPP_HAS_NO_RVALUE_REFERENCES) && !defined(_LIBCPP_HAS_NO_VARIADICS)
1750        _LIBCPP_INLINE_VISIBILITY
1751        void
1752        construct(pointer __p)
1753        {
1754            ::new((void*)__p) _Tp();
1755        }
1756# if defined(_LIBCPP_HAS_NO_RVALUE_REFERENCES)
1757
1758    template <class _A0>
1759        _LIBCPP_INLINE_VISIBILITY
1760        void
1761        construct(pointer __p, _A0& __a0)
1762        {
1763            ::new((void*)__p) _Tp(__a0);
1764        }
1765    template <class _A0>
1766        _LIBCPP_INLINE_VISIBILITY
1767        void
1768        construct(pointer __p, const _A0& __a0)
1769        {
1770            ::new((void*)__p) _Tp(__a0);
1771        }
1772# endif  // defined(_LIBCPP_HAS_NO_RVALUE_REFERENCES)
1773    template <class _A0, class _A1>
1774        _LIBCPP_INLINE_VISIBILITY
1775        void
1776        construct(pointer __p, _A0& __a0, _A1& __a1)
1777        {
1778            ::new((void*)__p) _Tp(__a0, __a1);
1779        }
1780    template <class _A0, class _A1>
1781        _LIBCPP_INLINE_VISIBILITY
1782        void
1783        construct(pointer __p, const _A0& __a0, _A1& __a1)
1784        {
1785            ::new((void*)__p) _Tp(__a0, __a1);
1786        }
1787    template <class _A0, class _A1>
1788        _LIBCPP_INLINE_VISIBILITY
1789        void
1790        construct(pointer __p, _A0& __a0, const _A1& __a1)
1791        {
1792            ::new((void*)__p) _Tp(__a0, __a1);
1793        }
1794    template <class _A0, class _A1>
1795        _LIBCPP_INLINE_VISIBILITY
1796        void
1797        construct(pointer __p, const _A0& __a0, const _A1& __a1)
1798        {
1799            ::new((void*)__p) _Tp(__a0, __a1);
1800        }
1801#endif  // !defined(_LIBCPP_HAS_NO_RVALUE_REFERENCES) && !defined(_LIBCPP_HAS_NO_VARIADICS)
1802    _LIBCPP_INLINE_VISIBILITY void destroy(pointer __p) {__p->~_Tp();}
1803};
1804
1805template <class _Tp>
1806class _LIBCPP_TYPE_VIS_ONLY allocator<const _Tp>
1807{
1808public:
1809    typedef size_t            size_type;
1810    typedef ptrdiff_t         difference_type;
1811    typedef const _Tp*        pointer;
1812    typedef const _Tp*        const_pointer;
1813    typedef const _Tp&        reference;
1814    typedef const _Tp&        const_reference;
1815    typedef const _Tp         value_type;
1816
1817    typedef true_type propagate_on_container_move_assignment;
1818    typedef true_type is_always_equal;
1819
1820    template <class _Up> struct rebind {typedef allocator<_Up> other;};
1821
1822    _LIBCPP_INLINE_VISIBILITY allocator() _NOEXCEPT {}
1823    template <class _Up> _LIBCPP_INLINE_VISIBILITY allocator(const allocator<_Up>&) _NOEXCEPT {}
1824    _LIBCPP_INLINE_VISIBILITY const_pointer address(const_reference __x) const _NOEXCEPT
1825        {return _VSTD::addressof(__x);}
1826    _LIBCPP_INLINE_VISIBILITY pointer allocate(size_type __n, allocator<void>::const_pointer = 0)
1827    {
1828        if (__n > max_size())
1829            __libcpp_throw(length_error("allocator<const T>::allocate(size_t n)"
1830                                      " 'n' exceeds maximum supported size"));
1831        return static_cast<pointer>(_VSTD::__allocate(__n * sizeof(_Tp)));
1832    }
1833    _LIBCPP_INLINE_VISIBILITY void deallocate(pointer __p, size_type) _NOEXCEPT
1834        {_VSTD::__deallocate((void*)__p);}
1835    _LIBCPP_INLINE_VISIBILITY size_type max_size() const _NOEXCEPT
1836        {return size_type(~0) / sizeof(_Tp);}
1837#if !defined(_LIBCPP_HAS_NO_RVALUE_REFERENCES) && !defined(_LIBCPP_HAS_NO_VARIADICS)
1838    template <class _Up, class... _Args>
1839        _LIBCPP_INLINE_VISIBILITY
1840        void
1841        construct(_Up* __p, _Args&&... __args)
1842        {
1843            ::new((void*)__p) _Up(_VSTD::forward<_Args>(__args)...);
1844        }
1845#else  // !defined(_LIBCPP_HAS_NO_RVALUE_REFERENCES) && !defined(_LIBCPP_HAS_NO_VARIADICS)
1846        _LIBCPP_INLINE_VISIBILITY
1847        void
1848        construct(pointer __p)
1849        {
1850            ::new((void*)__p) _Tp();
1851        }
1852# if defined(_LIBCPP_HAS_NO_RVALUE_REFERENCES)
1853
1854    template <class _A0>
1855        _LIBCPP_INLINE_VISIBILITY
1856        void
1857        construct(pointer __p, _A0& __a0)
1858        {
1859            ::new((void*)__p) _Tp(__a0);
1860        }
1861    template <class _A0>
1862        _LIBCPP_INLINE_VISIBILITY
1863        void
1864        construct(pointer __p, const _A0& __a0)
1865        {
1866            ::new((void*)__p) _Tp(__a0);
1867        }
1868# endif  // defined(_LIBCPP_HAS_NO_RVALUE_REFERENCES)
1869    template <class _A0, class _A1>
1870        _LIBCPP_INLINE_VISIBILITY
1871        void
1872        construct(pointer __p, _A0& __a0, _A1& __a1)
1873        {
1874            ::new((void*)__p) _Tp(__a0, __a1);
1875        }
1876    template <class _A0, class _A1>
1877        _LIBCPP_INLINE_VISIBILITY
1878        void
1879        construct(pointer __p, const _A0& __a0, _A1& __a1)
1880        {
1881            ::new((void*)__p) _Tp(__a0, __a1);
1882        }
1883    template <class _A0, class _A1>
1884        _LIBCPP_INLINE_VISIBILITY
1885        void
1886        construct(pointer __p, _A0& __a0, const _A1& __a1)
1887        {
1888            ::new((void*)__p) _Tp(__a0, __a1);
1889        }
1890    template <class _A0, class _A1>
1891        _LIBCPP_INLINE_VISIBILITY
1892        void
1893        construct(pointer __p, const _A0& __a0, const _A1& __a1)
1894        {
1895            ::new((void*)__p) _Tp(__a0, __a1);
1896        }
1897#endif  // !defined(_LIBCPP_HAS_NO_RVALUE_REFERENCES) && !defined(_LIBCPP_HAS_NO_VARIADICS)
1898    _LIBCPP_INLINE_VISIBILITY void destroy(pointer __p) {__p->~_Tp();}
1899};
1900
1901template <class _Tp, class _Up>
1902inline _LIBCPP_INLINE_VISIBILITY
1903bool operator==(const allocator<_Tp>&, const allocator<_Up>&) _NOEXCEPT {return true;}
1904
1905template <class _Tp, class _Up>
1906inline _LIBCPP_INLINE_VISIBILITY
1907bool operator!=(const allocator<_Tp>&, const allocator<_Up>&) _NOEXCEPT {return false;}
1908
1909template <class _OutputIterator, class _Tp>
1910class _LIBCPP_TYPE_VIS_ONLY raw_storage_iterator
1911    : public iterator<output_iterator_tag,
1912                      _Tp,                                         // purposefully not C++03
1913                      ptrdiff_t,                                   // purposefully not C++03
1914                      _Tp*,                                        // purposefully not C++03
1915                      raw_storage_iterator<_OutputIterator, _Tp>&> // purposefully not C++03
1916{
1917private:
1918    _OutputIterator __x_;
1919public:
1920    _LIBCPP_INLINE_VISIBILITY explicit raw_storage_iterator(_OutputIterator __x) : __x_(__x) {}
1921    _LIBCPP_INLINE_VISIBILITY raw_storage_iterator& operator*() {return *this;}
1922    _LIBCPP_INLINE_VISIBILITY raw_storage_iterator& operator=(const _Tp& __element)
1923        {::new(&*__x_) _Tp(__element); return *this;}
1924#if _LIBCPP_STD_VER >= 14
1925    _LIBCPP_INLINE_VISIBILITY raw_storage_iterator& operator=(_Tp&& __element)
1926        {::new(&*__x_) _Tp(_VSTD::move(__element)); return *this;}
1927#endif
1928    _LIBCPP_INLINE_VISIBILITY raw_storage_iterator& operator++() {++__x_; return *this;}
1929    _LIBCPP_INLINE_VISIBILITY raw_storage_iterator  operator++(int)
1930        {raw_storage_iterator __t(*this); ++__x_; return __t;}
1931#if _LIBCPP_STD_VER >= 14
1932    _LIBCPP_INLINE_VISIBILITY _OutputIterator base() const { return __x_; }
1933#endif
1934};
1935
1936template <class _Tp>
1937pair<_Tp*, ptrdiff_t>
1938get_temporary_buffer(ptrdiff_t __n) _NOEXCEPT
1939{
1940    pair<_Tp*, ptrdiff_t> __r(0, 0);
1941    const ptrdiff_t __m = (~ptrdiff_t(0) ^
1942                           ptrdiff_t(ptrdiff_t(1) << (sizeof(ptrdiff_t) * __CHAR_BIT__ - 1)))
1943                           / sizeof(_Tp);
1944    if (__n > __m)
1945        __n = __m;
1946    while (__n > 0)
1947    {
1948        __r.first = static_cast<_Tp*>(::operator new(__n * sizeof(_Tp), nothrow));
1949        if (__r.first)
1950        {
1951            __r.second = __n;
1952            break;
1953        }
1954        __n /= 2;
1955    }
1956    return __r;
1957}
1958
1959template <class _Tp>
1960inline _LIBCPP_INLINE_VISIBILITY
1961void return_temporary_buffer(_Tp* __p) _NOEXCEPT {::operator delete(__p);}
1962
1963template <class _Tp>
1964struct auto_ptr_ref
1965{
1966    _Tp* __ptr_;
1967};
1968
1969template<class _Tp>
1970class _LIBCPP_TYPE_VIS_ONLY auto_ptr
1971{
1972private:
1973    _Tp* __ptr_;
1974public:
1975    typedef _Tp element_type;
1976
1977    _LIBCPP_INLINE_VISIBILITY explicit auto_ptr(_Tp* __p = 0) throw() : __ptr_(__p) {}
1978    _LIBCPP_INLINE_VISIBILITY auto_ptr(auto_ptr& __p) throw() : __ptr_(__p.release()) {}
1979    template<class _Up> _LIBCPP_INLINE_VISIBILITY auto_ptr(auto_ptr<_Up>& __p) throw()
1980        : __ptr_(__p.release()) {}
1981    _LIBCPP_INLINE_VISIBILITY auto_ptr& operator=(auto_ptr& __p) throw()
1982        {reset(__p.release()); return *this;}
1983    template<class _Up> _LIBCPP_INLINE_VISIBILITY auto_ptr& operator=(auto_ptr<_Up>& __p) throw()
1984        {reset(__p.release()); return *this;}
1985    _LIBCPP_INLINE_VISIBILITY auto_ptr& operator=(auto_ptr_ref<_Tp> __p) throw()
1986        {reset(__p.__ptr_); return *this;}
1987    _LIBCPP_INLINE_VISIBILITY ~auto_ptr() throw() {delete __ptr_;}
1988
1989    _LIBCPP_INLINE_VISIBILITY _Tp& operator*() const throw()
1990        {return *__ptr_;}
1991    _LIBCPP_INLINE_VISIBILITY _Tp* operator->() const throw() {return __ptr_;}
1992    _LIBCPP_INLINE_VISIBILITY _Tp* get() const throw() {return __ptr_;}
1993    _LIBCPP_INLINE_VISIBILITY _Tp* release() throw()
1994    {
1995        _Tp* __t = __ptr_;
1996        __ptr_ = 0;
1997        return __t;
1998    }
1999    _LIBCPP_INLINE_VISIBILITY void reset(_Tp* __p = 0) throw()
2000    {
2001        if (__ptr_ != __p)
2002            delete __ptr_;
2003        __ptr_ = __p;
2004    }
2005
2006    _LIBCPP_INLINE_VISIBILITY auto_ptr(auto_ptr_ref<_Tp> __p) throw() : __ptr_(__p.__ptr_) {}
2007    template<class _Up> _LIBCPP_INLINE_VISIBILITY operator auto_ptr_ref<_Up>() throw()
2008        {auto_ptr_ref<_Up> __t; __t.__ptr_ = release(); return __t;}
2009    template<class _Up> _LIBCPP_INLINE_VISIBILITY operator auto_ptr<_Up>() throw()
2010        {return auto_ptr<_Up>(release());}
2011};
2012
2013template <>
2014class _LIBCPP_TYPE_VIS_ONLY auto_ptr<void>
2015{
2016public:
2017    typedef void element_type;
2018};
2019
2020template <class _T1, class _T2, bool = is_same<typename remove_cv<_T1>::type,
2021                                                     typename remove_cv<_T2>::type>::value,
2022                                bool = is_empty<_T1>::value
2023                                       && !__libcpp_is_final<_T1>::value,
2024                                bool = is_empty<_T2>::value
2025                                       && !__libcpp_is_final<_T2>::value
2026         >
2027struct __libcpp_compressed_pair_switch;
2028
2029template <class _T1, class _T2, bool IsSame>
2030struct __libcpp_compressed_pair_switch<_T1, _T2, IsSame, false, false> {enum {value = 0};};
2031
2032template <class _T1, class _T2, bool IsSame>
2033struct __libcpp_compressed_pair_switch<_T1, _T2, IsSame, true, false>  {enum {value = 1};};
2034
2035template <class _T1, class _T2, bool IsSame>
2036struct __libcpp_compressed_pair_switch<_T1, _T2, IsSame, false, true>  {enum {value = 2};};
2037
2038template <class _T1, class _T2>
2039struct __libcpp_compressed_pair_switch<_T1, _T2, false, true, true>    {enum {value = 3};};
2040
2041template <class _T1, class _T2>
2042struct __libcpp_compressed_pair_switch<_T1, _T2, true, true, true>     {enum {value = 1};};
2043
2044template <class _T1, class _T2, unsigned = __libcpp_compressed_pair_switch<_T1, _T2>::value>
2045class __libcpp_compressed_pair_imp;
2046
2047template <class _T1, class _T2>
2048class __libcpp_compressed_pair_imp<_T1, _T2, 0>
2049{
2050private:
2051    _T1 __first_;
2052    _T2 __second_;
2053public:
2054    typedef _T1 _T1_param;
2055    typedef _T2 _T2_param;
2056
2057    typedef typename remove_reference<_T1>::type& _T1_reference;
2058    typedef typename remove_reference<_T2>::type& _T2_reference;
2059
2060    typedef const typename remove_reference<_T1>::type& _T1_const_reference;
2061    typedef const typename remove_reference<_T2>::type& _T2_const_reference;
2062
2063    _LIBCPP_INLINE_VISIBILITY __libcpp_compressed_pair_imp() : __first_(), __second_() {}
2064    _LIBCPP_INLINE_VISIBILITY explicit __libcpp_compressed_pair_imp(_T1_param __t1)
2065        : __first_(_VSTD::forward<_T1_param>(__t1)), __second_() {}
2066    _LIBCPP_INLINE_VISIBILITY explicit __libcpp_compressed_pair_imp(_T2_param __t2)
2067        : __first_(), __second_(_VSTD::forward<_T2_param>(__t2)) {}
2068    _LIBCPP_INLINE_VISIBILITY __libcpp_compressed_pair_imp(_T1_param __t1, _T2_param __t2)
2069        : __first_(_VSTD::forward<_T1_param>(__t1)), __second_(_VSTD::forward<_T2_param>(__t2)) {}
2070
2071#if defined(_LIBCPP_HAS_NO_DEFAULTED_FUNCTIONS) && !defined(_LIBCPP_HAS_NO_RVALUE_REFERENCES)
2072
2073    _LIBCPP_INLINE_VISIBILITY
2074    __libcpp_compressed_pair_imp(const __libcpp_compressed_pair_imp& __p)
2075        _NOEXCEPT_(is_nothrow_copy_constructible<_T1>::value &&
2076                   is_nothrow_copy_constructible<_T2>::value)
2077        : __first_(__p.first()),
2078          __second_(__p.second()) {}
2079
2080    _LIBCPP_INLINE_VISIBILITY
2081    __libcpp_compressed_pair_imp& operator=(const __libcpp_compressed_pair_imp& __p)
2082        _NOEXCEPT_(is_nothrow_copy_assignable<_T1>::value &&
2083                   is_nothrow_copy_assignable<_T2>::value)
2084        {
2085            __first_ = __p.first();
2086            __second_ = __p.second();
2087            return *this;
2088        }
2089
2090    _LIBCPP_INLINE_VISIBILITY
2091    __libcpp_compressed_pair_imp(__libcpp_compressed_pair_imp&& __p)
2092        _NOEXCEPT_(is_nothrow_move_constructible<_T1>::value &&
2093                   is_nothrow_move_constructible<_T2>::value)
2094        : __first_(_VSTD::forward<_T1>(__p.first())),
2095          __second_(_VSTD::forward<_T2>(__p.second())) {}
2096
2097    _LIBCPP_INLINE_VISIBILITY
2098    __libcpp_compressed_pair_imp& operator=(__libcpp_compressed_pair_imp&& __p)
2099        _NOEXCEPT_(is_nothrow_move_assignable<_T1>::value &&
2100                   is_nothrow_move_assignable<_T2>::value)
2101        {
2102            __first_ = _VSTD::forward<_T1>(__p.first());
2103            __second_ = _VSTD::forward<_T2>(__p.second());
2104            return *this;
2105        }
2106
2107#endif  // defined(_LIBCPP_HAS_NO_DEFAULTED_FUNCTIONS) && !defined(_LIBCPP_HAS_NO_RVALUE_REFERENCES)
2108
2109#ifndef _LIBCPP_HAS_NO_VARIADICS
2110
2111    template <class... _Args1, class... _Args2, size_t... _I1, size_t... _I2>
2112        _LIBCPP_INLINE_VISIBILITY
2113        __libcpp_compressed_pair_imp(piecewise_construct_t __pc,
2114                                     tuple<_Args1...> __first_args,
2115                                     tuple<_Args2...> __second_args,
2116                                     __tuple_indices<_I1...>,
2117                                     __tuple_indices<_I2...>)
2118            : __first_(_VSTD::forward<_Args1>(_VSTD::get<_I1>(__first_args))...),
2119              __second_(_VSTD::forward<_Args2>(_VSTD::get<_I2>(__second_args))...)
2120            {}
2121
2122#endif  // _LIBCPP_HAS_NO_VARIADICS
2123
2124    _LIBCPP_INLINE_VISIBILITY _T1_reference       first() _NOEXCEPT       {return __first_;}
2125    _LIBCPP_INLINE_VISIBILITY _T1_const_reference first() const _NOEXCEPT {return __first_;}
2126
2127    _LIBCPP_INLINE_VISIBILITY _T2_reference       second() _NOEXCEPT       {return __second_;}
2128    _LIBCPP_INLINE_VISIBILITY _T2_const_reference second() const _NOEXCEPT {return __second_;}
2129
2130    _LIBCPP_INLINE_VISIBILITY void swap(__libcpp_compressed_pair_imp& __x)
2131        _NOEXCEPT_(__is_nothrow_swappable<_T1>::value &&
2132                   __is_nothrow_swappable<_T2>::value)
2133    {
2134        using _VSTD::swap;
2135        swap(__first_, __x.__first_);
2136        swap(__second_, __x.__second_);
2137    }
2138};
2139
2140template <class _T1, class _T2>
2141class __libcpp_compressed_pair_imp<_T1, _T2, 1>
2142    : private _T1
2143{
2144private:
2145    _T2 __second_;
2146public:
2147    typedef _T1 _T1_param;
2148    typedef _T2 _T2_param;
2149
2150    typedef _T1&                                        _T1_reference;
2151    typedef typename remove_reference<_T2>::type& _T2_reference;
2152
2153    typedef const _T1&                                        _T1_const_reference;
2154    typedef const typename remove_reference<_T2>::type& _T2_const_reference;
2155
2156    _LIBCPP_INLINE_VISIBILITY __libcpp_compressed_pair_imp() : __second_() {}
2157    _LIBCPP_INLINE_VISIBILITY explicit __libcpp_compressed_pair_imp(_T1_param __t1)
2158        : _T1(_VSTD::forward<_T1_param>(__t1)), __second_() {}
2159    _LIBCPP_INLINE_VISIBILITY explicit __libcpp_compressed_pair_imp(_T2_param __t2)
2160        : __second_(_VSTD::forward<_T2_param>(__t2)) {}
2161    _LIBCPP_INLINE_VISIBILITY __libcpp_compressed_pair_imp(_T1_param __t1, _T2_param __t2)
2162        : _T1(_VSTD::forward<_T1_param>(__t1)), __second_(_VSTD::forward<_T2_param>(__t2)) {}
2163
2164#if defined(_LIBCPP_HAS_NO_DEFAULTED_FUNCTIONS) && !defined(_LIBCPP_HAS_NO_RVALUE_REFERENCES)
2165
2166    _LIBCPP_INLINE_VISIBILITY
2167    __libcpp_compressed_pair_imp(const __libcpp_compressed_pair_imp& __p)
2168        _NOEXCEPT_(is_nothrow_copy_constructible<_T1>::value &&
2169                   is_nothrow_copy_constructible<_T2>::value)
2170        : _T1(__p.first()), __second_(__p.second()) {}
2171
2172    _LIBCPP_INLINE_VISIBILITY
2173    __libcpp_compressed_pair_imp& operator=(const __libcpp_compressed_pair_imp& __p)
2174        _NOEXCEPT_(is_nothrow_copy_assignable<_T1>::value &&
2175                   is_nothrow_copy_assignable<_T2>::value)
2176        {
2177            _T1::operator=(__p.first());
2178            __second_ = __p.second();
2179            return *this;
2180        }
2181
2182    _LIBCPP_INLINE_VISIBILITY
2183    __libcpp_compressed_pair_imp(__libcpp_compressed_pair_imp&& __p)
2184        _NOEXCEPT_(is_nothrow_move_constructible<_T1>::value &&
2185                   is_nothrow_move_constructible<_T2>::value)
2186        : _T1(_VSTD::move(__p.first())), __second_(_VSTD::forward<_T2>(__p.second())) {}
2187
2188    _LIBCPP_INLINE_VISIBILITY
2189    __libcpp_compressed_pair_imp& operator=(__libcpp_compressed_pair_imp&& __p)
2190        _NOEXCEPT_(is_nothrow_move_assignable<_T1>::value &&
2191                   is_nothrow_move_assignable<_T2>::value)
2192        {
2193            _T1::operator=(_VSTD::move(__p.first()));
2194            __second_ = _VSTD::forward<_T2>(__p.second());
2195            return *this;
2196        }
2197
2198#endif  // defined(_LIBCPP_HAS_NO_DEFAULTED_FUNCTIONS) && !defined(_LIBCPP_HAS_NO_RVALUE_REFERENCES)
2199
2200#ifndef _LIBCPP_HAS_NO_VARIADICS
2201
2202    template <class... _Args1, class... _Args2, size_t... _I1, size_t... _I2>
2203        _LIBCPP_INLINE_VISIBILITY
2204        __libcpp_compressed_pair_imp(piecewise_construct_t __pc,
2205                                     tuple<_Args1...> __first_args,
2206                                     tuple<_Args2...> __second_args,
2207                                     __tuple_indices<_I1...>,
2208                                     __tuple_indices<_I2...>)
2209            : _T1(_VSTD::forward<_Args1>(_VSTD::get<_I1>(__first_args))...),
2210              __second_(_VSTD::forward<_Args2>(_VSTD::get<_I2>(__second_args))...)
2211            {}
2212
2213#endif  // _LIBCPP_HAS_NO_VARIADICS
2214
2215    _LIBCPP_INLINE_VISIBILITY _T1_reference       first() _NOEXCEPT       {return *this;}
2216    _LIBCPP_INLINE_VISIBILITY _T1_const_reference first() const _NOEXCEPT {return *this;}
2217
2218    _LIBCPP_INLINE_VISIBILITY _T2_reference       second() _NOEXCEPT       {return __second_;}
2219    _LIBCPP_INLINE_VISIBILITY _T2_const_reference second() const _NOEXCEPT {return __second_;}
2220
2221    _LIBCPP_INLINE_VISIBILITY void swap(__libcpp_compressed_pair_imp& __x)
2222        _NOEXCEPT_(__is_nothrow_swappable<_T1>::value &&
2223                   __is_nothrow_swappable<_T2>::value)
2224    {
2225        using _VSTD::swap;
2226        swap(__second_, __x.__second_);
2227    }
2228};
2229
2230template <class _T1, class _T2>
2231class __libcpp_compressed_pair_imp<_T1, _T2, 2>
2232    : private _T2
2233{
2234private:
2235    _T1 __first_;
2236public:
2237    typedef _T1 _T1_param;
2238    typedef _T2 _T2_param;
2239
2240    typedef typename remove_reference<_T1>::type& _T1_reference;
2241    typedef _T2&                                        _T2_reference;
2242
2243    typedef const typename remove_reference<_T1>::type& _T1_const_reference;
2244    typedef const _T2&                                        _T2_const_reference;
2245
2246    _LIBCPP_INLINE_VISIBILITY __libcpp_compressed_pair_imp() : __first_() {}
2247    _LIBCPP_INLINE_VISIBILITY explicit __libcpp_compressed_pair_imp(_T1_param __t1)
2248        : __first_(_VSTD::forward<_T1_param>(__t1)) {}
2249    _LIBCPP_INLINE_VISIBILITY explicit __libcpp_compressed_pair_imp(_T2_param __t2)
2250        : _T2(_VSTD::forward<_T2_param>(__t2)), __first_() {}
2251    _LIBCPP_INLINE_VISIBILITY __libcpp_compressed_pair_imp(_T1_param __t1, _T2_param __t2)
2252        _NOEXCEPT_(is_nothrow_move_constructible<_T1>::value &&
2253                   is_nothrow_move_constructible<_T2>::value)
2254        : _T2(_VSTD::forward<_T2_param>(__t2)), __first_(_VSTD::forward<_T1_param>(__t1)) {}
2255
2256#if defined(_LIBCPP_HAS_NO_DEFAULTED_FUNCTIONS) && !defined(_LIBCPP_HAS_NO_RVALUE_REFERENCES)
2257
2258    _LIBCPP_INLINE_VISIBILITY
2259    __libcpp_compressed_pair_imp(const __libcpp_compressed_pair_imp& __p)
2260        _NOEXCEPT_(is_nothrow_copy_constructible<_T1>::value &&
2261                   is_nothrow_copy_constructible<_T2>::value)
2262        : _T2(__p.second()), __first_(__p.first()) {}
2263
2264    _LIBCPP_INLINE_VISIBILITY
2265    __libcpp_compressed_pair_imp& operator=(const __libcpp_compressed_pair_imp& __p)
2266        _NOEXCEPT_(is_nothrow_copy_assignable<_T1>::value &&
2267                   is_nothrow_copy_assignable<_T2>::value)
2268        {
2269            _T2::operator=(__p.second());
2270            __first_ = __p.first();
2271            return *this;
2272        }
2273
2274    _LIBCPP_INLINE_VISIBILITY
2275    __libcpp_compressed_pair_imp(__libcpp_compressed_pair_imp&& __p)
2276        _NOEXCEPT_(is_nothrow_move_constructible<_T1>::value &&
2277                   is_nothrow_move_constructible<_T2>::value)
2278        : _T2(_VSTD::forward<_T2>(__p.second())), __first_(_VSTD::move(__p.first())) {}
2279
2280    _LIBCPP_INLINE_VISIBILITY
2281    __libcpp_compressed_pair_imp& operator=(__libcpp_compressed_pair_imp&& __p)
2282        _NOEXCEPT_(is_nothrow_move_assignable<_T1>::value &&
2283                   is_nothrow_move_assignable<_T2>::value)
2284        {
2285            _T2::operator=(_VSTD::forward<_T2>(__p.second()));
2286            __first_ = _VSTD::move(__p.first());
2287            return *this;
2288        }
2289
2290#endif  // defined(_LIBCPP_HAS_NO_DEFAULTED_FUNCTIONS) && !defined(_LIBCPP_HAS_NO_RVALUE_REFERENCES)
2291
2292#ifndef _LIBCPP_HAS_NO_VARIADICS
2293
2294    template <class... _Args1, class... _Args2, size_t... _I1, size_t... _I2>
2295        _LIBCPP_INLINE_VISIBILITY
2296        __libcpp_compressed_pair_imp(piecewise_construct_t __pc,
2297                                     tuple<_Args1...> __first_args,
2298                                     tuple<_Args2...> __second_args,
2299                                     __tuple_indices<_I1...>,
2300                                     __tuple_indices<_I2...>)
2301            : _T2(_VSTD::forward<_Args2>(_VSTD::get<_I2>(__second_args))...),
2302              __first_(_VSTD::forward<_Args1>(_VSTD::get<_I1>(__first_args))...)
2303
2304            {}
2305
2306#endif  // _LIBCPP_HAS_NO_VARIADICS
2307
2308    _LIBCPP_INLINE_VISIBILITY _T1_reference       first() _NOEXCEPT       {return __first_;}
2309    _LIBCPP_INLINE_VISIBILITY _T1_const_reference first() const _NOEXCEPT {return __first_;}
2310
2311    _LIBCPP_INLINE_VISIBILITY _T2_reference       second() _NOEXCEPT       {return *this;}
2312    _LIBCPP_INLINE_VISIBILITY _T2_const_reference second() const _NOEXCEPT {return *this;}
2313
2314    _LIBCPP_INLINE_VISIBILITY void swap(__libcpp_compressed_pair_imp& __x)
2315        _NOEXCEPT_(__is_nothrow_swappable<_T1>::value &&
2316                   __is_nothrow_swappable<_T2>::value)
2317    {
2318        using _VSTD::swap;
2319        swap(__first_, __x.__first_);
2320    }
2321};
2322
2323template <class _T1, class _T2>
2324class __libcpp_compressed_pair_imp<_T1, _T2, 3>
2325    : private _T1,
2326      private _T2
2327{
2328public:
2329    typedef _T1 _T1_param;
2330    typedef _T2 _T2_param;
2331
2332    typedef _T1& _T1_reference;
2333    typedef _T2& _T2_reference;
2334
2335    typedef const _T1& _T1_const_reference;
2336    typedef const _T2& _T2_const_reference;
2337
2338    _LIBCPP_INLINE_VISIBILITY __libcpp_compressed_pair_imp() {}
2339    _LIBCPP_INLINE_VISIBILITY explicit __libcpp_compressed_pair_imp(_T1_param __t1)
2340        : _T1(_VSTD::forward<_T1_param>(__t1)) {}
2341    _LIBCPP_INLINE_VISIBILITY explicit __libcpp_compressed_pair_imp(_T2_param __t2)
2342        : _T2(_VSTD::forward<_T2_param>(__t2)) {}
2343    _LIBCPP_INLINE_VISIBILITY __libcpp_compressed_pair_imp(_T1_param __t1, _T2_param __t2)
2344        : _T1(_VSTD::forward<_T1_param>(__t1)), _T2(_VSTD::forward<_T2_param>(__t2)) {}
2345
2346#if defined(_LIBCPP_HAS_NO_DEFAULTED_FUNCTIONS) && !defined(_LIBCPP_HAS_NO_RVALUE_REFERENCES)
2347
2348    _LIBCPP_INLINE_VISIBILITY
2349    __libcpp_compressed_pair_imp(const __libcpp_compressed_pair_imp& __p)
2350        _NOEXCEPT_(is_nothrow_copy_constructible<_T1>::value &&
2351                   is_nothrow_copy_constructible<_T2>::value)
2352        : _T1(__p.first()), _T2(__p.second()) {}
2353
2354    _LIBCPP_INLINE_VISIBILITY
2355    __libcpp_compressed_pair_imp& operator=(const __libcpp_compressed_pair_imp& __p)
2356        _NOEXCEPT_(is_nothrow_copy_assignable<_T1>::value &&
2357                   is_nothrow_copy_assignable<_T2>::value)
2358        {
2359            _T1::operator=(__p.first());
2360            _T2::operator=(__p.second());
2361            return *this;
2362        }
2363
2364    _LIBCPP_INLINE_VISIBILITY
2365    __libcpp_compressed_pair_imp(__libcpp_compressed_pair_imp&& __p)
2366        _NOEXCEPT_(is_nothrow_move_constructible<_T1>::value &&
2367                   is_nothrow_move_constructible<_T2>::value)
2368        : _T1(_VSTD::move(__p.first())), _T2(_VSTD::move(__p.second())) {}
2369
2370    _LIBCPP_INLINE_VISIBILITY
2371    __libcpp_compressed_pair_imp& operator=(__libcpp_compressed_pair_imp&& __p)
2372        _NOEXCEPT_(is_nothrow_move_assignable<_T1>::value &&
2373                   is_nothrow_move_assignable<_T2>::value)
2374        {
2375            _T1::operator=(_VSTD::move(__p.first()));
2376            _T2::operator=(_VSTD::move(__p.second()));
2377            return *this;
2378        }
2379
2380#endif  // defined(_LIBCPP_HAS_NO_DEFAULTED_FUNCTIONS) && !defined(_LIBCPP_HAS_NO_RVALUE_REFERENCES)
2381
2382#ifndef _LIBCPP_HAS_NO_VARIADICS
2383
2384    template <class... _Args1, class... _Args2, size_t... _I1, size_t... _I2>
2385        _LIBCPP_INLINE_VISIBILITY
2386        __libcpp_compressed_pair_imp(piecewise_construct_t __pc,
2387                                     tuple<_Args1...> __first_args,
2388                                     tuple<_Args2...> __second_args,
2389                                     __tuple_indices<_I1...>,
2390                                     __tuple_indices<_I2...>)
2391            : _T1(_VSTD::forward<_Args1>(_VSTD::get<_I1>(__first_args))...),
2392              _T2(_VSTD::forward<_Args2>(_VSTD::get<_I2>(__second_args))...)
2393            {}
2394
2395#endif  // _LIBCPP_HAS_NO_VARIADICS
2396
2397    _LIBCPP_INLINE_VISIBILITY _T1_reference       first() _NOEXCEPT       {return *this;}
2398    _LIBCPP_INLINE_VISIBILITY _T1_const_reference first() const _NOEXCEPT {return *this;}
2399
2400    _LIBCPP_INLINE_VISIBILITY _T2_reference       second() _NOEXCEPT       {return *this;}
2401    _LIBCPP_INLINE_VISIBILITY _T2_const_reference second() const _NOEXCEPT {return *this;}
2402
2403    _LIBCPP_INLINE_VISIBILITY void swap(__libcpp_compressed_pair_imp&)
2404        _NOEXCEPT_(__is_nothrow_swappable<_T1>::value &&
2405                   __is_nothrow_swappable<_T2>::value)
2406    {
2407    }
2408};
2409
2410template <class _T1, class _T2>
2411class __compressed_pair
2412    : private __libcpp_compressed_pair_imp<_T1, _T2>
2413{
2414    typedef __libcpp_compressed_pair_imp<_T1, _T2> base;
2415public:
2416    typedef typename base::_T1_param _T1_param;
2417    typedef typename base::_T2_param _T2_param;
2418
2419    typedef typename base::_T1_reference _T1_reference;
2420    typedef typename base::_T2_reference _T2_reference;
2421
2422    typedef typename base::_T1_const_reference _T1_const_reference;
2423    typedef typename base::_T2_const_reference _T2_const_reference;
2424
2425    _LIBCPP_INLINE_VISIBILITY __compressed_pair() {}
2426    _LIBCPP_INLINE_VISIBILITY explicit __compressed_pair(_T1_param __t1)
2427        : base(_VSTD::forward<_T1_param>(__t1)) {}
2428    _LIBCPP_INLINE_VISIBILITY explicit __compressed_pair(_T2_param __t2)
2429        : base(_VSTD::forward<_T2_param>(__t2)) {}
2430    _LIBCPP_INLINE_VISIBILITY __compressed_pair(_T1_param __t1, _T2_param __t2)
2431        : base(_VSTD::forward<_T1_param>(__t1), _VSTD::forward<_T2_param>(__t2)) {}
2432
2433#if defined(_LIBCPP_HAS_NO_DEFAULTED_FUNCTIONS) && !defined(_LIBCPP_HAS_NO_RVALUE_REFERENCES)
2434
2435    _LIBCPP_INLINE_VISIBILITY
2436    __compressed_pair(const __compressed_pair& __p)
2437        _NOEXCEPT_(is_nothrow_copy_constructible<_T1>::value &&
2438                   is_nothrow_copy_constructible<_T2>::value)
2439        : base(__p) {}
2440
2441    _LIBCPP_INLINE_VISIBILITY
2442    __compressed_pair& operator=(const __compressed_pair& __p)
2443        _NOEXCEPT_(is_nothrow_copy_assignable<_T1>::value &&
2444                   is_nothrow_copy_assignable<_T2>::value)
2445        {
2446            base::operator=(__p);
2447            return *this;
2448        }
2449
2450    _LIBCPP_INLINE_VISIBILITY
2451    __compressed_pair(__compressed_pair&& __p)
2452        _NOEXCEPT_(is_nothrow_move_constructible<_T1>::value &&
2453                   is_nothrow_move_constructible<_T2>::value)
2454        : base(_VSTD::move(__p)) {}
2455
2456    _LIBCPP_INLINE_VISIBILITY
2457    __compressed_pair& operator=(__compressed_pair&& __p)
2458        _NOEXCEPT_(is_nothrow_move_assignable<_T1>::value &&
2459                   is_nothrow_move_assignable<_T2>::value)
2460        {
2461            base::operator=(_VSTD::move(__p));
2462            return *this;
2463        }
2464
2465#endif  // defined(_LIBCPP_HAS_NO_DEFAULTED_FUNCTIONS) && !defined(_LIBCPP_HAS_NO_RVALUE_REFERENCES)
2466
2467#ifndef _LIBCPP_HAS_NO_VARIADICS
2468
2469    template <class... _Args1, class... _Args2>
2470        _LIBCPP_INLINE_VISIBILITY
2471        __compressed_pair(piecewise_construct_t __pc, tuple<_Args1...> __first_args,
2472                                                      tuple<_Args2...> __second_args)
2473            : base(__pc, _VSTD::move(__first_args), _VSTD::move(__second_args),
2474                   typename __make_tuple_indices<sizeof...(_Args1)>::type(),
2475                   typename __make_tuple_indices<sizeof...(_Args2) >::type())
2476            {}
2477
2478#endif  // _LIBCPP_HAS_NO_VARIADICS
2479
2480    _LIBCPP_INLINE_VISIBILITY _T1_reference       first() _NOEXCEPT       {return base::first();}
2481    _LIBCPP_INLINE_VISIBILITY _T1_const_reference first() const _NOEXCEPT {return base::first();}
2482
2483    _LIBCPP_INLINE_VISIBILITY _T2_reference       second() _NOEXCEPT       {return base::second();}
2484    _LIBCPP_INLINE_VISIBILITY _T2_const_reference second() const _NOEXCEPT {return base::second();}
2485
2486    _LIBCPP_INLINE_VISIBILITY void swap(__compressed_pair& __x)
2487        _NOEXCEPT_(__is_nothrow_swappable<_T1>::value &&
2488                   __is_nothrow_swappable<_T2>::value)
2489        {base::swap(__x);}
2490};
2491
2492template <class _T1, class _T2>
2493inline _LIBCPP_INLINE_VISIBILITY
2494void
2495swap(__compressed_pair<_T1, _T2>& __x, __compressed_pair<_T1, _T2>& __y)
2496        _NOEXCEPT_(__is_nothrow_swappable<_T1>::value &&
2497                   __is_nothrow_swappable<_T2>::value)
2498    {__x.swap(__y);}
2499
2500// __same_or_less_cv_qualified
2501
2502template <class _Ptr1, class _Ptr2,
2503          bool = is_same<typename remove_cv<typename pointer_traits<_Ptr1>::element_type>::type,
2504                         typename remove_cv<typename pointer_traits<_Ptr2>::element_type>::type
2505                        >::value
2506         >
2507struct __same_or_less_cv_qualified_imp
2508    : is_convertible<_Ptr1, _Ptr2> {};
2509
2510template <class _Ptr1, class _Ptr2>
2511struct __same_or_less_cv_qualified_imp<_Ptr1, _Ptr2, false>
2512    : false_type {};
2513
2514template <class _Ptr1, class _Ptr2, bool = is_pointer<_Ptr1>::value ||
2515                                           is_same<_Ptr1, _Ptr2>::value ||
2516                                           __has_element_type<_Ptr1>::value>
2517struct __same_or_less_cv_qualified
2518    : __same_or_less_cv_qualified_imp<_Ptr1, _Ptr2> {};
2519
2520template <class _Ptr1, class _Ptr2>
2521struct __same_or_less_cv_qualified<_Ptr1, _Ptr2, false>
2522    : false_type {};
2523
2524// default_delete
2525
2526template <class _Tp>
2527struct _LIBCPP_TYPE_VIS_ONLY default_delete
2528{
2529#ifndef _LIBCPP_HAS_NO_DEFAULTED_FUNCTIONS
2530    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR default_delete() _NOEXCEPT = default;
2531#else
2532    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR default_delete() _NOEXCEPT {}
2533#endif
2534    template <class _Up>
2535        _LIBCPP_INLINE_VISIBILITY default_delete(const default_delete<_Up>&,
2536             typename enable_if<is_convertible<_Up*, _Tp*>::value>::type* = 0) _NOEXCEPT {}
2537    _LIBCPP_INLINE_VISIBILITY void operator() (_Tp* __ptr) const _NOEXCEPT
2538        {
2539            static_assert(sizeof(_Tp) > 0, "default_delete can not delete incomplete type");
2540            static_assert(!is_void<_Tp>::value, "default_delete can not delete incomplete type");
2541            delete __ptr;
2542        }
2543};
2544
2545template <class _Tp>
2546struct _LIBCPP_TYPE_VIS_ONLY default_delete<_Tp[]>
2547{
2548public:
2549#ifndef _LIBCPP_HAS_NO_DEFAULTED_FUNCTIONS
2550    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR default_delete() _NOEXCEPT = default;
2551#else
2552    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR default_delete() _NOEXCEPT {}
2553#endif
2554    template <class _Up>
2555        _LIBCPP_INLINE_VISIBILITY default_delete(const default_delete<_Up[]>&,
2556             typename enable_if<__same_or_less_cv_qualified<_Up*, _Tp*>::value>::type* = 0) _NOEXCEPT {}
2557    template <class _Up>
2558        _LIBCPP_INLINE_VISIBILITY
2559        void operator() (_Up* __ptr,
2560                         typename enable_if<__same_or_less_cv_qualified<_Up*, _Tp*>::value>::type* = 0) const _NOEXCEPT
2561        {
2562            static_assert(sizeof(_Tp) > 0, "default_delete can not delete incomplete type");
2563            static_assert(!is_void<_Tp>::value, "default_delete can not delete void type");
2564            delete [] __ptr;
2565        }
2566};
2567
2568template <class _Tp, class _Dp = default_delete<_Tp> >
2569class _LIBCPP_TYPE_VIS_ONLY unique_ptr
2570{
2571public:
2572    typedef _Tp element_type;
2573    typedef _Dp deleter_type;
2574    typedef typename __pointer_type<_Tp, deleter_type>::type pointer;
2575private:
2576    __compressed_pair<pointer, deleter_type> __ptr_;
2577
2578#ifdef _LIBCPP_HAS_NO_RVALUE_REFERENCES
2579    unique_ptr(unique_ptr&);
2580    template <class _Up, class _Ep>
2581        unique_ptr(unique_ptr<_Up, _Ep>&);
2582    unique_ptr& operator=(unique_ptr&);
2583    template <class _Up, class _Ep>
2584        unique_ptr& operator=(unique_ptr<_Up, _Ep>&);
2585#endif  // _LIBCPP_HAS_NO_RVALUE_REFERENCES
2586
2587    struct __nat {int __for_bool_;};
2588
2589    typedef       typename remove_reference<deleter_type>::type& _Dp_reference;
2590    typedef const typename remove_reference<deleter_type>::type& _Dp_const_reference;
2591public:
2592    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR unique_ptr() _NOEXCEPT
2593        : __ptr_(pointer())
2594        {
2595            static_assert(!is_pointer<deleter_type>::value,
2596                "unique_ptr constructed with null function pointer deleter");
2597        }
2598    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR unique_ptr(nullptr_t) _NOEXCEPT
2599        : __ptr_(pointer())
2600        {
2601            static_assert(!is_pointer<deleter_type>::value,
2602                "unique_ptr constructed with null function pointer deleter");
2603        }
2604    _LIBCPP_INLINE_VISIBILITY explicit unique_ptr(pointer __p) _NOEXCEPT
2605        : __ptr_(_VSTD::move(__p))
2606        {
2607            static_assert(!is_pointer<deleter_type>::value,
2608                "unique_ptr constructed with null function pointer deleter");
2609        }
2610
2611#ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES
2612    _LIBCPP_INLINE_VISIBILITY unique_ptr(pointer __p, typename conditional<
2613                                        is_reference<deleter_type>::value,
2614                                        deleter_type,
2615                                        typename add_lvalue_reference<const deleter_type>::type>::type __d)
2616             _NOEXCEPT
2617        : __ptr_(__p, __d) {}
2618
2619    _LIBCPP_INLINE_VISIBILITY unique_ptr(pointer __p, typename remove_reference<deleter_type>::type&& __d)
2620             _NOEXCEPT
2621        : __ptr_(__p, _VSTD::move(__d))
2622        {
2623            static_assert(!is_reference<deleter_type>::value, "rvalue deleter bound to reference");
2624        }
2625    _LIBCPP_INLINE_VISIBILITY unique_ptr(unique_ptr&& __u) _NOEXCEPT
2626        : __ptr_(__u.release(), _VSTD::forward<deleter_type>(__u.get_deleter())) {}
2627    template <class _Up, class _Ep>
2628        _LIBCPP_INLINE_VISIBILITY
2629        unique_ptr(unique_ptr<_Up, _Ep>&& __u,
2630                   typename enable_if
2631                      <
2632                        !is_array<_Up>::value &&
2633                         is_convertible<typename unique_ptr<_Up, _Ep>::pointer, pointer>::value &&
2634                         is_convertible<_Ep, deleter_type>::value &&
2635                         (
2636                            !is_reference<deleter_type>::value ||
2637                            is_same<deleter_type, _Ep>::value
2638                         ),
2639                         __nat
2640                      >::type = __nat()) _NOEXCEPT
2641            : __ptr_(__u.release(), _VSTD::forward<_Ep>(__u.get_deleter())) {}
2642
2643    template <class _Up>
2644        _LIBCPP_INLINE_VISIBILITY unique_ptr(auto_ptr<_Up>&& __p,
2645                typename enable_if<
2646                                      is_convertible<_Up*, _Tp*>::value &&
2647                                      is_same<_Dp, default_delete<_Tp> >::value,
2648                                      __nat
2649                                  >::type = __nat()) _NOEXCEPT
2650            : __ptr_(__p.release())
2651            {
2652            }
2653
2654        _LIBCPP_INLINE_VISIBILITY unique_ptr& operator=(unique_ptr&& __u) _NOEXCEPT
2655            {
2656                reset(__u.release());
2657                __ptr_.second() = _VSTD::forward<deleter_type>(__u.get_deleter());
2658                return *this;
2659            }
2660
2661        template <class _Up, class _Ep>
2662            _LIBCPP_INLINE_VISIBILITY
2663            typename enable_if
2664            <
2665                !is_array<_Up>::value &&
2666                is_convertible<typename unique_ptr<_Up, _Ep>::pointer, pointer>::value &&
2667                is_assignable<deleter_type&, _Ep&&>::value,
2668                unique_ptr&
2669            >::type
2670            operator=(unique_ptr<_Up, _Ep>&& __u) _NOEXCEPT
2671            {
2672                reset(__u.release());
2673                __ptr_.second() = _VSTD::forward<_Ep>(__u.get_deleter());
2674                return *this;
2675            }
2676#else  // _LIBCPP_HAS_NO_RVALUE_REFERENCES
2677
2678    _LIBCPP_INLINE_VISIBILITY operator __rv<unique_ptr>()
2679    {
2680        return __rv<unique_ptr>(*this);
2681    }
2682
2683    _LIBCPP_INLINE_VISIBILITY unique_ptr(__rv<unique_ptr> __u)
2684        : __ptr_(__u->release(), _VSTD::forward<deleter_type>(__u->get_deleter())) {}
2685
2686    template <class _Up, class _Ep>
2687    _LIBCPP_INLINE_VISIBILITY
2688    typename enable_if<
2689        !is_array<_Up>::value &&
2690        is_convertible<typename unique_ptr<_Up, _Ep>::pointer, pointer>::value &&
2691        is_assignable<deleter_type&, _Ep&>::value,
2692        unique_ptr&
2693    >::type
2694    operator=(unique_ptr<_Up, _Ep> __u)
2695    {
2696        reset(__u.release());
2697        __ptr_.second() = _VSTD::forward<_Ep>(__u.get_deleter());
2698        return *this;
2699    }
2700
2701    _LIBCPP_INLINE_VISIBILITY unique_ptr(pointer __p, deleter_type __d)
2702        : __ptr_(_VSTD::move(__p), _VSTD::move(__d)) {}
2703
2704    template <class _Up>
2705        _LIBCPP_INLINE_VISIBILITY
2706                typename enable_if<
2707                                      is_convertible<_Up*, _Tp*>::value &&
2708                                      is_same<_Dp, default_delete<_Tp> >::value,
2709                                      unique_ptr&
2710                                  >::type
2711        operator=(auto_ptr<_Up> __p)
2712            {reset(__p.release()); return *this;}
2713
2714#endif  // _LIBCPP_HAS_NO_RVALUE_REFERENCES
2715    _LIBCPP_INLINE_VISIBILITY ~unique_ptr() {reset();}
2716
2717    _LIBCPP_INLINE_VISIBILITY unique_ptr& operator=(nullptr_t) _NOEXCEPT
2718    {
2719        reset();
2720        return *this;
2721    }
2722
2723    _LIBCPP_INLINE_VISIBILITY typename add_lvalue_reference<_Tp>::type operator*() const
2724        {return *__ptr_.first();}
2725    _LIBCPP_INLINE_VISIBILITY pointer operator->() const _NOEXCEPT {return __ptr_.first();}
2726    _LIBCPP_INLINE_VISIBILITY pointer get() const _NOEXCEPT {return __ptr_.first();}
2727    _LIBCPP_INLINE_VISIBILITY       _Dp_reference get_deleter() _NOEXCEPT
2728        {return __ptr_.second();}
2729    _LIBCPP_INLINE_VISIBILITY _Dp_const_reference get_deleter() const _NOEXCEPT
2730        {return __ptr_.second();}
2731    _LIBCPP_INLINE_VISIBILITY
2732        _LIBCPP_EXPLICIT operator bool() const _NOEXCEPT
2733        {return __ptr_.first() != nullptr;}
2734
2735    _LIBCPP_INLINE_VISIBILITY pointer release() _NOEXCEPT
2736    {
2737        pointer __t = __ptr_.first();
2738        __ptr_.first() = pointer();
2739        return __t;
2740    }
2741
2742    _LIBCPP_INLINE_VISIBILITY void reset(pointer __p = pointer()) _NOEXCEPT
2743    {
2744        pointer __tmp = __ptr_.first();
2745        __ptr_.first() = __p;
2746        if (__tmp)
2747            __ptr_.second()(__tmp);
2748    }
2749
2750    _LIBCPP_INLINE_VISIBILITY void swap(unique_ptr& __u) _NOEXCEPT
2751        {__ptr_.swap(__u.__ptr_);}
2752};
2753
2754template <class _Tp, class _Dp>
2755class _LIBCPP_TYPE_VIS_ONLY unique_ptr<_Tp[], _Dp>
2756{
2757public:
2758    typedef _Tp element_type;
2759    typedef _Dp deleter_type;
2760    typedef typename __pointer_type<_Tp, deleter_type>::type pointer;
2761private:
2762    __compressed_pair<pointer, deleter_type> __ptr_;
2763
2764#ifdef _LIBCPP_HAS_NO_RVALUE_REFERENCES
2765    unique_ptr(unique_ptr&);
2766    template <class _Up>
2767        unique_ptr(unique_ptr<_Up>&);
2768    unique_ptr& operator=(unique_ptr&);
2769    template <class _Up>
2770        unique_ptr& operator=(unique_ptr<_Up>&);
2771#endif  // _LIBCPP_HAS_NO_RVALUE_REFERENCES
2772
2773    struct __nat {int __for_bool_;};
2774
2775    typedef       typename remove_reference<deleter_type>::type& _Dp_reference;
2776    typedef const typename remove_reference<deleter_type>::type& _Dp_const_reference;
2777public:
2778    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR unique_ptr() _NOEXCEPT
2779        : __ptr_(pointer())
2780        {
2781            static_assert(!is_pointer<deleter_type>::value,
2782                "unique_ptr constructed with null function pointer deleter");
2783        }
2784    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR unique_ptr(nullptr_t) _NOEXCEPT
2785        : __ptr_(pointer())
2786        {
2787            static_assert(!is_pointer<deleter_type>::value,
2788                "unique_ptr constructed with null function pointer deleter");
2789        }
2790#ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES
2791    template <class _Pp>
2792    _LIBCPP_INLINE_VISIBILITY explicit unique_ptr(_Pp __p,
2793            typename enable_if<__same_or_less_cv_qualified<_Pp, pointer>::value, __nat>::type = __nat()) _NOEXCEPT
2794        : __ptr_(__p)
2795        {
2796            static_assert(!is_pointer<deleter_type>::value,
2797                "unique_ptr constructed with null function pointer deleter");
2798        }
2799
2800    template <class _Pp>
2801    _LIBCPP_INLINE_VISIBILITY unique_ptr(_Pp __p, typename conditional<
2802                                       is_reference<deleter_type>::value,
2803                                       deleter_type,
2804                                       typename add_lvalue_reference<const deleter_type>::type>::type __d,
2805                                       typename enable_if<__same_or_less_cv_qualified<_Pp, pointer>::value, __nat>::type = __nat())
2806             _NOEXCEPT
2807        : __ptr_(__p, __d) {}
2808
2809    _LIBCPP_INLINE_VISIBILITY unique_ptr(nullptr_t, typename conditional<
2810                                       is_reference<deleter_type>::value,
2811                                       deleter_type,
2812                                       typename add_lvalue_reference<const deleter_type>::type>::type __d)
2813             _NOEXCEPT
2814        : __ptr_(pointer(), __d) {}
2815
2816    template <class _Pp>
2817    _LIBCPP_INLINE_VISIBILITY unique_ptr(_Pp __p,
2818                                         typename remove_reference<deleter_type>::type&& __d,
2819                                         typename enable_if<__same_or_less_cv_qualified<_Pp, pointer>::value, __nat>::type = __nat())
2820             _NOEXCEPT
2821        : __ptr_(__p, _VSTD::move(__d))
2822        {
2823            static_assert(!is_reference<deleter_type>::value, "rvalue deleter bound to reference");
2824        }
2825
2826    _LIBCPP_INLINE_VISIBILITY unique_ptr(nullptr_t, typename remove_reference<deleter_type>::type&& __d)
2827             _NOEXCEPT
2828        : __ptr_(pointer(), _VSTD::move(__d))
2829        {
2830            static_assert(!is_reference<deleter_type>::value, "rvalue deleter bound to reference");
2831        }
2832
2833    _LIBCPP_INLINE_VISIBILITY unique_ptr(unique_ptr&& __u) _NOEXCEPT
2834        : __ptr_(__u.release(), _VSTD::forward<deleter_type>(__u.get_deleter())) {}
2835
2836    _LIBCPP_INLINE_VISIBILITY unique_ptr& operator=(unique_ptr&& __u) _NOEXCEPT
2837        {
2838            reset(__u.release());
2839            __ptr_.second() = _VSTD::forward<deleter_type>(__u.get_deleter());
2840            return *this;
2841        }
2842
2843    template <class _Up, class _Ep>
2844        _LIBCPP_INLINE_VISIBILITY
2845        unique_ptr(unique_ptr<_Up, _Ep>&& __u,
2846                   typename enable_if
2847                            <
2848                                is_array<_Up>::value &&
2849                                __same_or_less_cv_qualified<typename unique_ptr<_Up, _Ep>::pointer, pointer>::value
2850                                && is_convertible<_Ep, deleter_type>::value &&
2851                                (
2852                                    !is_reference<deleter_type>::value ||
2853                                    is_same<deleter_type, _Ep>::value
2854                                ),
2855                                __nat
2856                            >::type = __nat()
2857                  ) _NOEXCEPT
2858        : __ptr_(__u.release(), _VSTD::forward<deleter_type>(__u.get_deleter())) {}
2859
2860
2861        template <class _Up, class _Ep>
2862            _LIBCPP_INLINE_VISIBILITY
2863            typename enable_if
2864            <
2865                is_array<_Up>::value &&
2866                __same_or_less_cv_qualified<typename unique_ptr<_Up, _Ep>::pointer, pointer>::value &&
2867                is_assignable<deleter_type&, _Ep&&>::value,
2868                unique_ptr&
2869            >::type
2870            operator=(unique_ptr<_Up, _Ep>&& __u) _NOEXCEPT
2871            {
2872                reset(__u.release());
2873                __ptr_.second() = _VSTD::forward<_Ep>(__u.get_deleter());
2874                return *this;
2875            }
2876#else  // _LIBCPP_HAS_NO_RVALUE_REFERENCES
2877
2878    _LIBCPP_INLINE_VISIBILITY explicit unique_ptr(pointer __p)
2879        : __ptr_(__p)
2880        {
2881            static_assert(!is_pointer<deleter_type>::value,
2882                "unique_ptr constructed with null function pointer deleter");
2883        }
2884
2885    _LIBCPP_INLINE_VISIBILITY unique_ptr(pointer __p, deleter_type __d)
2886        : __ptr_(__p, _VSTD::forward<deleter_type>(__d)) {}
2887
2888    _LIBCPP_INLINE_VISIBILITY unique_ptr(nullptr_t, deleter_type __d)
2889        : __ptr_(pointer(), _VSTD::forward<deleter_type>(__d)) {}
2890
2891    _LIBCPP_INLINE_VISIBILITY operator __rv<unique_ptr>()
2892    {
2893        return __rv<unique_ptr>(*this);
2894    }
2895
2896    _LIBCPP_INLINE_VISIBILITY unique_ptr(__rv<unique_ptr> __u)
2897        : __ptr_(__u->release(), _VSTD::forward<deleter_type>(__u->get_deleter())) {}
2898
2899    _LIBCPP_INLINE_VISIBILITY unique_ptr& operator=(__rv<unique_ptr> __u)
2900    {
2901        reset(__u->release());
2902        __ptr_.second() = _VSTD::forward<deleter_type>(__u->get_deleter());
2903        return *this;
2904    }
2905
2906#endif  // _LIBCPP_HAS_NO_RVALUE_REFERENCES
2907    _LIBCPP_INLINE_VISIBILITY ~unique_ptr() {reset();}
2908
2909    _LIBCPP_INLINE_VISIBILITY unique_ptr& operator=(nullptr_t) _NOEXCEPT
2910    {
2911        reset();
2912        return *this;
2913    }
2914
2915    _LIBCPP_INLINE_VISIBILITY typename add_lvalue_reference<_Tp>::type operator[](size_t __i) const
2916        {return __ptr_.first()[__i];}
2917    _LIBCPP_INLINE_VISIBILITY pointer get() const _NOEXCEPT {return __ptr_.first();}
2918    _LIBCPP_INLINE_VISIBILITY       _Dp_reference get_deleter() _NOEXCEPT
2919        {return __ptr_.second();}
2920    _LIBCPP_INLINE_VISIBILITY _Dp_const_reference get_deleter() const _NOEXCEPT
2921        {return __ptr_.second();}
2922    _LIBCPP_INLINE_VISIBILITY
2923        _LIBCPP_EXPLICIT operator bool() const _NOEXCEPT
2924        {return __ptr_.first() != nullptr;}
2925
2926    _LIBCPP_INLINE_VISIBILITY pointer release() _NOEXCEPT
2927    {
2928        pointer __t = __ptr_.first();
2929        __ptr_.first() = pointer();
2930        return __t;
2931    }
2932
2933    template <class _Pp>
2934    _LIBCPP_INLINE_VISIBILITY
2935    typename enable_if<__same_or_less_cv_qualified<_Pp, pointer>::value, void>::type
2936    reset(_Pp __p) _NOEXCEPT
2937    {
2938        pointer __tmp = __ptr_.first();
2939        __ptr_.first() = __p;
2940        if (__tmp)
2941            __ptr_.second()(__tmp);
2942    }
2943    _LIBCPP_INLINE_VISIBILITY void reset(nullptr_t = nullptr) _NOEXCEPT
2944    {
2945        pointer __tmp = __ptr_.first();
2946        __ptr_.first() = nullptr;
2947        if (__tmp)
2948            __ptr_.second()(__tmp);
2949    }
2950
2951    _LIBCPP_INLINE_VISIBILITY void swap(unique_ptr& __u) {__ptr_.swap(__u.__ptr_);}
2952private:
2953
2954#ifdef _LIBCPP_HAS_NO_RVALUE_REFERENCES
2955    template <class _Up>
2956        explicit unique_ptr(_Up);
2957    template <class _Up>
2958        unique_ptr(_Up __u,
2959                   typename conditional<
2960                                       is_reference<deleter_type>::value,
2961                                       deleter_type,
2962                                       typename add_lvalue_reference<const deleter_type>::type>::type,
2963                   typename enable_if
2964                      <
2965                         is_convertible<_Up, pointer>::value,
2966                         __nat
2967                      >::type = __nat());
2968#endif  // _LIBCPP_HAS_NO_RVALUE_REFERENCES
2969};
2970
2971template <class _Tp, class _Dp>
2972inline _LIBCPP_INLINE_VISIBILITY
2973typename enable_if<
2974    __is_swappable<_Dp>::value,
2975    void
2976>::type
2977swap(unique_ptr<_Tp, _Dp>& __x, unique_ptr<_Tp, _Dp>& __y) _NOEXCEPT {__x.swap(__y);}
2978
2979template <class _T1, class _D1, class _T2, class _D2>
2980inline _LIBCPP_INLINE_VISIBILITY
2981bool
2982operator==(const unique_ptr<_T1, _D1>& __x, const unique_ptr<_T2, _D2>& __y) {return __x.get() == __y.get();}
2983
2984template <class _T1, class _D1, class _T2, class _D2>
2985inline _LIBCPP_INLINE_VISIBILITY
2986bool
2987operator!=(const unique_ptr<_T1, _D1>& __x, const unique_ptr<_T2, _D2>& __y) {return !(__x == __y);}
2988
2989template <class _T1, class _D1, class _T2, class _D2>
2990inline _LIBCPP_INLINE_VISIBILITY
2991bool
2992operator< (const unique_ptr<_T1, _D1>& __x, const unique_ptr<_T2, _D2>& __y)
2993{
2994    typedef typename unique_ptr<_T1, _D1>::pointer _P1;
2995    typedef typename unique_ptr<_T2, _D2>::pointer _P2;
2996    typedef typename common_type<_P1, _P2>::type _Vp;
2997    return less<_Vp>()(__x.get(), __y.get());
2998}
2999
3000template <class _T1, class _D1, class _T2, class _D2>
3001inline _LIBCPP_INLINE_VISIBILITY
3002bool
3003operator> (const unique_ptr<_T1, _D1>& __x, const unique_ptr<_T2, _D2>& __y) {return __y < __x;}
3004
3005template <class _T1, class _D1, class _T2, class _D2>
3006inline _LIBCPP_INLINE_VISIBILITY
3007bool
3008operator<=(const unique_ptr<_T1, _D1>& __x, const unique_ptr<_T2, _D2>& __y) {return !(__y < __x);}
3009
3010template <class _T1, class _D1, class _T2, class _D2>
3011inline _LIBCPP_INLINE_VISIBILITY
3012bool
3013operator>=(const unique_ptr<_T1, _D1>& __x, const unique_ptr<_T2, _D2>& __y) {return !(__x < __y);}
3014
3015template <class _T1, class _D1>
3016inline _LIBCPP_INLINE_VISIBILITY
3017bool
3018operator==(const unique_ptr<_T1, _D1>& __x, nullptr_t) _NOEXCEPT
3019{
3020    return !__x;
3021}
3022
3023template <class _T1, class _D1>
3024inline _LIBCPP_INLINE_VISIBILITY
3025bool
3026operator==(nullptr_t, const unique_ptr<_T1, _D1>& __x) _NOEXCEPT
3027{
3028    return !__x;
3029}
3030
3031template <class _T1, class _D1>
3032inline _LIBCPP_INLINE_VISIBILITY
3033bool
3034operator!=(const unique_ptr<_T1, _D1>& __x, nullptr_t) _NOEXCEPT
3035{
3036    return static_cast<bool>(__x);
3037}
3038
3039template <class _T1, class _D1>
3040inline _LIBCPP_INLINE_VISIBILITY
3041bool
3042operator!=(nullptr_t, const unique_ptr<_T1, _D1>& __x) _NOEXCEPT
3043{
3044    return static_cast<bool>(__x);
3045}
3046
3047template <class _T1, class _D1>
3048inline _LIBCPP_INLINE_VISIBILITY
3049bool
3050operator<(const unique_ptr<_T1, _D1>& __x, nullptr_t)
3051{
3052    typedef typename unique_ptr<_T1, _D1>::pointer _P1;
3053    return less<_P1>()(__x.get(), nullptr);
3054}
3055
3056template <class _T1, class _D1>
3057inline _LIBCPP_INLINE_VISIBILITY
3058bool
3059operator<(nullptr_t, const unique_ptr<_T1, _D1>& __x)
3060{
3061    typedef typename unique_ptr<_T1, _D1>::pointer _P1;
3062    return less<_P1>()(nullptr, __x.get());
3063}
3064
3065template <class _T1, class _D1>
3066inline _LIBCPP_INLINE_VISIBILITY
3067bool
3068operator>(const unique_ptr<_T1, _D1>& __x, nullptr_t)
3069{
3070    return nullptr < __x;
3071}
3072
3073template <class _T1, class _D1>
3074inline _LIBCPP_INLINE_VISIBILITY
3075bool
3076operator>(nullptr_t, const unique_ptr<_T1, _D1>& __x)
3077{
3078    return __x < nullptr;
3079}
3080
3081template <class _T1, class _D1>
3082inline _LIBCPP_INLINE_VISIBILITY
3083bool
3084operator<=(const unique_ptr<_T1, _D1>& __x, nullptr_t)
3085{
3086    return !(nullptr < __x);
3087}
3088
3089template <class _T1, class _D1>
3090inline _LIBCPP_INLINE_VISIBILITY
3091bool
3092operator<=(nullptr_t, const unique_ptr<_T1, _D1>& __x)
3093{
3094    return !(__x < nullptr);
3095}
3096
3097template <class _T1, class _D1>
3098inline _LIBCPP_INLINE_VISIBILITY
3099bool
3100operator>=(const unique_ptr<_T1, _D1>& __x, nullptr_t)
3101{
3102    return !(__x < nullptr);
3103}
3104
3105template <class _T1, class _D1>
3106inline _LIBCPP_INLINE_VISIBILITY
3107bool
3108operator>=(nullptr_t, const unique_ptr<_T1, _D1>& __x)
3109{
3110    return !(nullptr < __x);
3111}
3112
3113#ifdef _LIBCPP_HAS_NO_RVALUE_REFERENCES
3114
3115template <class _Tp, class _Dp>
3116inline _LIBCPP_INLINE_VISIBILITY
3117unique_ptr<_Tp, _Dp>
3118move(unique_ptr<_Tp, _Dp>& __t)
3119{
3120    return unique_ptr<_Tp, _Dp>(__rv<unique_ptr<_Tp, _Dp> >(__t));
3121}
3122
3123#endif
3124
3125#if _LIBCPP_STD_VER > 11
3126
3127template<class _Tp>
3128struct __unique_if
3129{
3130    typedef unique_ptr<_Tp> __unique_single;
3131};
3132
3133template<class _Tp>
3134struct __unique_if<_Tp[]>
3135{
3136    typedef unique_ptr<_Tp[]> __unique_array_unknown_bound;
3137};
3138
3139template<class _Tp, size_t _Np>
3140struct __unique_if<_Tp[_Np]>
3141{
3142    typedef void __unique_array_known_bound;
3143};
3144
3145template<class _Tp, class... _Args>
3146inline _LIBCPP_INLINE_VISIBILITY
3147typename __unique_if<_Tp>::__unique_single
3148make_unique(_Args&&... __args)
3149{
3150    return unique_ptr<_Tp>(new _Tp(_VSTD::forward<_Args>(__args)...));
3151}
3152
3153template<class _Tp>
3154inline _LIBCPP_INLINE_VISIBILITY
3155typename __unique_if<_Tp>::__unique_array_unknown_bound
3156make_unique(size_t __n)
3157{
3158    typedef typename remove_extent<_Tp>::type _Up;
3159    return unique_ptr<_Tp>(new _Up[__n]());
3160}
3161
3162template<class _Tp, class... _Args>
3163    typename __unique_if<_Tp>::__unique_array_known_bound
3164    make_unique(_Args&&...) = delete;
3165
3166#endif  // _LIBCPP_STD_VER > 11
3167
3168template <class _Size>
3169inline _LIBCPP_INLINE_VISIBILITY
3170_Size
3171__loadword(const void* __p)
3172{
3173    _Size __r;
3174    std::memcpy(&__r, __p, sizeof(__r));
3175    return __r;
3176}
3177
3178// We use murmur2 when size_t is 32 bits, and cityhash64 when size_t
3179// is 64 bits.  This is because cityhash64 uses 64bit x 64bit
3180// multiplication, which can be very slow on 32-bit systems.
3181template <class _Size, size_t = sizeof(_Size)*__CHAR_BIT__>
3182struct __murmur2_or_cityhash;
3183
3184template <class _Size>
3185struct __murmur2_or_cityhash<_Size, 32>
3186{
3187    _Size operator()(const void* __key, _Size __len);
3188};
3189
3190// murmur2
3191template <class _Size>
3192_Size
3193__murmur2_or_cityhash<_Size, 32>::operator()(const void* __key, _Size __len) _LIBCPP_DISABLE_UBSAN_UNSIGNED_INTEGER_CHECK
3194{
3195    const _Size __m = 0x5bd1e995;
3196    const _Size __r = 24;
3197    _Size __h = __len;
3198    const unsigned char* __data = static_cast<const unsigned char*>(__key);
3199    for (; __len >= 4; __data += 4, __len -= 4)
3200    {
3201        _Size __k = __loadword<_Size>(__data);
3202        __k *= __m;
3203        __k ^= __k >> __r;
3204        __k *= __m;
3205        __h *= __m;
3206        __h ^= __k;
3207    }
3208    switch (__len)
3209    {
3210    case 3:
3211        __h ^= __data[2] << 16;
3212    case 2:
3213        __h ^= __data[1] << 8;
3214    case 1:
3215        __h ^= __data[0];
3216        __h *= __m;
3217    }
3218    __h ^= __h >> 13;
3219    __h *= __m;
3220    __h ^= __h >> 15;
3221    return __h;
3222}
3223
3224template <class _Size>
3225struct __murmur2_or_cityhash<_Size, 64>
3226{
3227    _Size operator()(const void* __key, _Size __len);
3228
3229 private:
3230  // Some primes between 2^63 and 2^64.
3231  static const _Size __k0 = 0xc3a5c85c97cb3127ULL;
3232  static const _Size __k1 = 0xb492b66fbe98f273ULL;
3233  static const _Size __k2 = 0x9ae16a3b2f90404fULL;
3234  static const _Size __k3 = 0xc949d7c7509e6557ULL;
3235
3236  static _Size __rotate(_Size __val, int __shift) {
3237    return __shift == 0 ? __val : ((__val >> __shift) | (__val << (64 - __shift)));
3238  }
3239
3240  static _Size __rotate_by_at_least_1(_Size __val, int __shift) {
3241    return (__val >> __shift) | (__val << (64 - __shift));
3242  }
3243
3244  static _Size __shift_mix(_Size __val) {
3245    return __val ^ (__val >> 47);
3246  }
3247
3248  static _Size __hash_len_16(_Size __u, _Size __v) {
3249    const _Size __mul = 0x9ddfea08eb382d69ULL;
3250    _Size __a = (__u ^ __v) * __mul;
3251    __a ^= (__a >> 47);
3252    _Size __b = (__v ^ __a) * __mul;
3253    __b ^= (__b >> 47);
3254    __b *= __mul;
3255    return __b;
3256  }
3257
3258  static _Size __hash_len_0_to_16(const char* __s, _Size __len) {
3259    if (__len > 8) {
3260      const _Size __a = __loadword<_Size>(__s);
3261      const _Size __b = __loadword<_Size>(__s + __len - 8);
3262      return __hash_len_16(__a, __rotate_by_at_least_1(__b + __len, __len)) ^ __b;
3263    }
3264    if (__len >= 4) {
3265      const uint32_t __a = __loadword<uint32_t>(__s);
3266      const uint32_t __b = __loadword<uint32_t>(__s + __len - 4);
3267      return __hash_len_16(__len + (__a << 3), __b);
3268    }
3269    if (__len > 0) {
3270      const unsigned char __a = __s[0];
3271      const unsigned char __b = __s[__len >> 1];
3272      const unsigned char __c = __s[__len - 1];
3273      const uint32_t __y = static_cast<uint32_t>(__a) +
3274                           (static_cast<uint32_t>(__b) << 8);
3275      const uint32_t __z = __len + (static_cast<uint32_t>(__c) << 2);
3276      return __shift_mix(__y * __k2 ^ __z * __k3) * __k2;
3277    }
3278    return __k2;
3279  }
3280
3281  static _Size __hash_len_17_to_32(const char *__s, _Size __len) {
3282    const _Size __a = __loadword<_Size>(__s) * __k1;
3283    const _Size __b = __loadword<_Size>(__s + 8);
3284    const _Size __c = __loadword<_Size>(__s + __len - 8) * __k2;
3285    const _Size __d = __loadword<_Size>(__s + __len - 16) * __k0;
3286    return __hash_len_16(__rotate(__a - __b, 43) + __rotate(__c, 30) + __d,
3287                         __a + __rotate(__b ^ __k3, 20) - __c + __len);
3288  }
3289
3290  // Return a 16-byte hash for 48 bytes.  Quick and dirty.
3291  // Callers do best to use "random-looking" values for a and b.
3292  static pair<_Size, _Size> __weak_hash_len_32_with_seeds(
3293      _Size __w, _Size __x, _Size __y, _Size __z, _Size __a, _Size __b) {
3294    __a += __w;
3295    __b = __rotate(__b + __a + __z, 21);
3296    const _Size __c = __a;
3297    __a += __x;
3298    __a += __y;
3299    __b += __rotate(__a, 44);
3300    return pair<_Size, _Size>(__a + __z, __b + __c);
3301  }
3302
3303  // Return a 16-byte hash for s[0] ... s[31], a, and b.  Quick and dirty.
3304  static pair<_Size, _Size> __weak_hash_len_32_with_seeds(
3305      const char* __s, _Size __a, _Size __b) {
3306    return __weak_hash_len_32_with_seeds(__loadword<_Size>(__s),
3307                                         __loadword<_Size>(__s + 8),
3308                                         __loadword<_Size>(__s + 16),
3309                                         __loadword<_Size>(__s + 24),
3310                                         __a,
3311                                         __b);
3312  }
3313
3314  // Return an 8-byte hash for 33 to 64 bytes.
3315  static _Size __hash_len_33_to_64(const char *__s, size_t __len) {
3316    _Size __z = __loadword<_Size>(__s + 24);
3317    _Size __a = __loadword<_Size>(__s) +
3318                (__len + __loadword<_Size>(__s + __len - 16)) * __k0;
3319    _Size __b = __rotate(__a + __z, 52);
3320    _Size __c = __rotate(__a, 37);
3321    __a += __loadword<_Size>(__s + 8);
3322    __c += __rotate(__a, 7);
3323    __a += __loadword<_Size>(__s + 16);
3324    _Size __vf = __a + __z;
3325    _Size __vs = __b + __rotate(__a, 31) + __c;
3326    __a = __loadword<_Size>(__s + 16) + __loadword<_Size>(__s + __len - 32);
3327    __z += __loadword<_Size>(__s + __len - 8);
3328    __b = __rotate(__a + __z, 52);
3329    __c = __rotate(__a, 37);
3330    __a += __loadword<_Size>(__s + __len - 24);
3331    __c += __rotate(__a, 7);
3332    __a += __loadword<_Size>(__s + __len - 16);
3333    _Size __wf = __a + __z;
3334    _Size __ws = __b + __rotate(__a, 31) + __c;
3335    _Size __r = __shift_mix((__vf + __ws) * __k2 + (__wf + __vs) * __k0);
3336    return __shift_mix(__r * __k0 + __vs) * __k2;
3337  }
3338};
3339
3340// cityhash64
3341template <class _Size>
3342_Size
3343__murmur2_or_cityhash<_Size, 64>::operator()(const void* __key, _Size __len) _LIBCPP_DISABLE_UBSAN_UNSIGNED_INTEGER_CHECK
3344{
3345  const char* __s = static_cast<const char*>(__key);
3346  if (__len <= 32) {
3347    if (__len <= 16) {
3348      return __hash_len_0_to_16(__s, __len);
3349    } else {
3350      return __hash_len_17_to_32(__s, __len);
3351    }
3352  } else if (__len <= 64) {
3353    return __hash_len_33_to_64(__s, __len);
3354  }
3355
3356  // For strings over 64 bytes we hash the end first, and then as we
3357  // loop we keep 56 bytes of state: v, w, x, y, and z.
3358  _Size __x = __loadword<_Size>(__s + __len - 40);
3359  _Size __y = __loadword<_Size>(__s + __len - 16) +
3360              __loadword<_Size>(__s + __len - 56);
3361  _Size __z = __hash_len_16(__loadword<_Size>(__s + __len - 48) + __len,
3362                          __loadword<_Size>(__s + __len - 24));
3363  pair<_Size, _Size> __v = __weak_hash_len_32_with_seeds(__s + __len - 64, __len, __z);
3364  pair<_Size, _Size> __w = __weak_hash_len_32_with_seeds(__s + __len - 32, __y + __k1, __x);
3365  __x = __x * __k1 + __loadword<_Size>(__s);
3366
3367  // Decrease len to the nearest multiple of 64, and operate on 64-byte chunks.
3368  __len = (__len - 1) & ~static_cast<_Size>(63);
3369  do {
3370    __x = __rotate(__x + __y + __v.first + __loadword<_Size>(__s + 8), 37) * __k1;
3371    __y = __rotate(__y + __v.second + __loadword<_Size>(__s + 48), 42) * __k1;
3372    __x ^= __w.second;
3373    __y += __v.first + __loadword<_Size>(__s + 40);
3374    __z = __rotate(__z + __w.first, 33) * __k1;
3375    __v = __weak_hash_len_32_with_seeds(__s, __v.second * __k1, __x + __w.first);
3376    __w = __weak_hash_len_32_with_seeds(__s + 32, __z + __w.second,
3377                                        __y + __loadword<_Size>(__s + 16));
3378    std::swap(__z, __x);
3379    __s += 64;
3380    __len -= 64;
3381  } while (__len != 0);
3382  return __hash_len_16(
3383      __hash_len_16(__v.first, __w.first) + __shift_mix(__y) * __k1 + __z,
3384      __hash_len_16(__v.second, __w.second) + __x);
3385}
3386
3387template <class _Tp, size_t = sizeof(_Tp) / sizeof(size_t)>
3388struct __scalar_hash;
3389
3390template <class _Tp>
3391struct __scalar_hash<_Tp, 0>
3392    : public unary_function<_Tp, size_t>
3393{
3394    _LIBCPP_INLINE_VISIBILITY
3395    size_t operator()(_Tp __v) const _NOEXCEPT
3396    {
3397        union
3398        {
3399            _Tp    __t;
3400            size_t __a;
3401        } __u;
3402        __u.__a = 0;
3403        __u.__t = __v;
3404        return __u.__a;
3405    }
3406};
3407
3408template <class _Tp>
3409struct __scalar_hash<_Tp, 1>
3410    : public unary_function<_Tp, size_t>
3411{
3412    _LIBCPP_INLINE_VISIBILITY
3413    size_t operator()(_Tp __v) const _NOEXCEPT
3414    {
3415        union
3416        {
3417            _Tp    __t;
3418            size_t __a;
3419        } __u;
3420        __u.__t = __v;
3421        return __u.__a;
3422    }
3423};
3424
3425template <class _Tp>
3426struct __scalar_hash<_Tp, 2>
3427    : public unary_function<_Tp, size_t>
3428{
3429    _LIBCPP_INLINE_VISIBILITY
3430    size_t operator()(_Tp __v) const _NOEXCEPT
3431    {
3432        union
3433        {
3434            _Tp __t;
3435            struct
3436            {
3437                size_t __a;
3438                size_t __b;
3439            } __s;
3440        } __u;
3441        __u.__t = __v;
3442        return __murmur2_or_cityhash<size_t>()(&__u, sizeof(__u));
3443    }
3444};
3445
3446template <class _Tp>
3447struct __scalar_hash<_Tp, 3>
3448    : public unary_function<_Tp, size_t>
3449{
3450    _LIBCPP_INLINE_VISIBILITY
3451    size_t operator()(_Tp __v) const _NOEXCEPT
3452    {
3453        union
3454        {
3455            _Tp __t;
3456            struct
3457            {
3458                size_t __a;
3459                size_t __b;
3460                size_t __c;
3461            } __s;
3462        } __u;
3463        __u.__t = __v;
3464        return __murmur2_or_cityhash<size_t>()(&__u, sizeof(__u));
3465    }
3466};
3467
3468template <class _Tp>
3469struct __scalar_hash<_Tp, 4>
3470    : public unary_function<_Tp, size_t>
3471{
3472    _LIBCPP_INLINE_VISIBILITY
3473    size_t operator()(_Tp __v) const _NOEXCEPT
3474    {
3475        union
3476        {
3477            _Tp __t;
3478            struct
3479            {
3480                size_t __a;
3481                size_t __b;
3482                size_t __c;
3483                size_t __d;
3484            } __s;
3485        } __u;
3486        __u.__t = __v;
3487        return __murmur2_or_cityhash<size_t>()(&__u, sizeof(__u));
3488    }
3489};
3490
3491template<class _Tp>
3492struct _LIBCPP_TYPE_VIS_ONLY hash<_Tp*>
3493    : public unary_function<_Tp*, size_t>
3494{
3495    _LIBCPP_INLINE_VISIBILITY
3496    size_t operator()(_Tp* __v) const _NOEXCEPT
3497    {
3498        union
3499        {
3500            _Tp* __t;
3501            size_t __a;
3502        } __u;
3503        __u.__t = __v;
3504        return __murmur2_or_cityhash<size_t>()(&__u, sizeof(__u));
3505    }
3506};
3507
3508template <class _Tp, class _Dp>
3509struct _LIBCPP_TYPE_VIS_ONLY hash<unique_ptr<_Tp, _Dp> >
3510{
3511    typedef unique_ptr<_Tp, _Dp> argument_type;
3512    typedef size_t               result_type;
3513    _LIBCPP_INLINE_VISIBILITY
3514    result_type operator()(const argument_type& __ptr) const _NOEXCEPT
3515    {
3516        typedef typename argument_type::pointer pointer;
3517        return hash<pointer>()(__ptr.get());
3518    }
3519};
3520
3521struct __destruct_n
3522{
3523private:
3524    size_t size;
3525
3526    template <class _Tp>
3527    _LIBCPP_INLINE_VISIBILITY void __process(_Tp* __p, false_type) _NOEXCEPT
3528        {for (size_t __i = 0; __i < size; ++__i, ++__p) __p->~_Tp();}
3529
3530    template <class _Tp>
3531    _LIBCPP_INLINE_VISIBILITY void __process(_Tp*, true_type) _NOEXCEPT
3532        {}
3533
3534    _LIBCPP_INLINE_VISIBILITY void __incr(false_type) _NOEXCEPT
3535        {++size;}
3536    _LIBCPP_INLINE_VISIBILITY void __incr(true_type) _NOEXCEPT
3537        {}
3538
3539    _LIBCPP_INLINE_VISIBILITY void __set(size_t __s, false_type) _NOEXCEPT
3540        {size = __s;}
3541    _LIBCPP_INLINE_VISIBILITY void __set(size_t, true_type) _NOEXCEPT
3542        {}
3543public:
3544    _LIBCPP_INLINE_VISIBILITY explicit __destruct_n(size_t __s) _NOEXCEPT
3545        : size(__s) {}
3546
3547    template <class _Tp>
3548    _LIBCPP_INLINE_VISIBILITY void __incr(_Tp*) _NOEXCEPT
3549        {__incr(integral_constant<bool, is_trivially_destructible<_Tp>::value>());}
3550
3551    template <class _Tp>
3552    _LIBCPP_INLINE_VISIBILITY void __set(size_t __s, _Tp*) _NOEXCEPT
3553        {__set(__s, integral_constant<bool, is_trivially_destructible<_Tp>::value>());}
3554
3555    template <class _Tp>
3556    _LIBCPP_INLINE_VISIBILITY void operator()(_Tp* __p) _NOEXCEPT
3557        {__process(__p, integral_constant<bool, is_trivially_destructible<_Tp>::value>());}
3558};
3559
3560template <class _Alloc>
3561class __allocator_destructor
3562{
3563    typedef allocator_traits<_Alloc> __alloc_traits;
3564public:
3565    typedef typename __alloc_traits::pointer pointer;
3566    typedef typename __alloc_traits::size_type size_type;
3567private:
3568    _Alloc& __alloc_;
3569    size_type __s_;
3570public:
3571    _LIBCPP_INLINE_VISIBILITY __allocator_destructor(_Alloc& __a, size_type __s)
3572             _NOEXCEPT
3573        : __alloc_(__a), __s_(__s) {}
3574    _LIBCPP_INLINE_VISIBILITY
3575    void operator()(pointer __p) _NOEXCEPT
3576        {__alloc_traits::deallocate(__alloc_, __p, __s_);}
3577};
3578
3579template <class _InputIterator, class _ForwardIterator>
3580_ForwardIterator
3581uninitialized_copy(_InputIterator __f, _InputIterator __l, _ForwardIterator __r)
3582{
3583    typedef typename iterator_traits<_ForwardIterator>::value_type value_type;
3584#ifndef _LIBCPP_NO_EXCEPTIONS
3585    _ForwardIterator __s = __r;
3586    try
3587    {
3588#endif
3589        for (; __f != __l; ++__f, (void) ++__r)
3590            ::new (static_cast<void*>(_VSTD::addressof(*__r))) value_type(*__f);
3591#ifndef _LIBCPP_NO_EXCEPTIONS
3592    }
3593    catch (...)
3594    {
3595        for (; __s != __r; ++__s)
3596            __s->~value_type();
3597        throw;
3598    }
3599#endif
3600    return __r;
3601}
3602
3603template <class _InputIterator, class _Size, class _ForwardIterator>
3604_ForwardIterator
3605uninitialized_copy_n(_InputIterator __f, _Size __n, _ForwardIterator __r)
3606{
3607    typedef typename iterator_traits<_ForwardIterator>::value_type value_type;
3608#ifndef _LIBCPP_NO_EXCEPTIONS
3609    _ForwardIterator __s = __r;
3610    try
3611    {
3612#endif
3613        for (; __n > 0; ++__f, (void) ++__r, (void) --__n)
3614            ::new (static_cast<void*>(_VSTD::addressof(*__r))) value_type(*__f);
3615#ifndef _LIBCPP_NO_EXCEPTIONS
3616    }
3617    catch (...)
3618    {
3619        for (; __s != __r; ++__s)
3620            __s->~value_type();
3621        throw;
3622    }
3623#endif
3624    return __r;
3625}
3626
3627template <class _ForwardIterator, class _Tp>
3628void
3629uninitialized_fill(_ForwardIterator __f, _ForwardIterator __l, const _Tp& __x)
3630{
3631    typedef typename iterator_traits<_ForwardIterator>::value_type value_type;
3632#ifndef _LIBCPP_NO_EXCEPTIONS
3633    _ForwardIterator __s = __f;
3634    try
3635    {
3636#endif
3637        for (; __f != __l; ++__f)
3638            ::new (static_cast<void*>(_VSTD::addressof(*__f))) value_type(__x);
3639#ifndef _LIBCPP_NO_EXCEPTIONS
3640    }
3641    catch (...)
3642    {
3643        for (; __s != __f; ++__s)
3644            __s->~value_type();
3645        throw;
3646    }
3647#endif
3648}
3649
3650template <class _ForwardIterator, class _Size, class _Tp>
3651_ForwardIterator
3652uninitialized_fill_n(_ForwardIterator __f, _Size __n, const _Tp& __x)
3653{
3654    typedef typename iterator_traits<_ForwardIterator>::value_type value_type;
3655#ifndef _LIBCPP_NO_EXCEPTIONS
3656    _ForwardIterator __s = __f;
3657    try
3658    {
3659#endif
3660        for (; __n > 0; ++__f, (void) --__n)
3661            ::new (static_cast<void*>(_VSTD::addressof(*__f))) value_type(__x);
3662#ifndef _LIBCPP_NO_EXCEPTIONS
3663    }
3664    catch (...)
3665    {
3666        for (; __s != __f; ++__s)
3667            __s->~value_type();
3668        throw;
3669    }
3670#endif
3671    return __f;
3672}
3673
3674class _LIBCPP_EXCEPTION_ABI bad_weak_ptr
3675    : public std::exception
3676{
3677public:
3678    virtual ~bad_weak_ptr() _NOEXCEPT;
3679    virtual const char* what() const  _NOEXCEPT;
3680};
3681
3682template<class _Tp> class _LIBCPP_TYPE_VIS_ONLY weak_ptr;
3683
3684class _LIBCPP_TYPE_VIS __shared_count
3685{
3686    __shared_count(const __shared_count&);
3687    __shared_count& operator=(const __shared_count&);
3688
3689protected:
3690    long __shared_owners_;
3691    virtual ~__shared_count();
3692private:
3693    virtual void __on_zero_shared() _NOEXCEPT = 0;
3694
3695public:
3696    _LIBCPP_INLINE_VISIBILITY
3697    explicit __shared_count(long __refs = 0) _NOEXCEPT
3698        : __shared_owners_(__refs) {}
3699
3700    void __add_shared() _NOEXCEPT;
3701    bool __release_shared() _NOEXCEPT;
3702    _LIBCPP_INLINE_VISIBILITY
3703    long use_count() const _NOEXCEPT {
3704        return __libcpp_relaxed_load(&__shared_owners_) + 1;
3705    }
3706};
3707
3708class _LIBCPP_TYPE_VIS __shared_weak_count
3709    : private __shared_count
3710{
3711    long __shared_weak_owners_;
3712
3713public:
3714    _LIBCPP_INLINE_VISIBILITY
3715    explicit __shared_weak_count(long __refs = 0) _NOEXCEPT
3716        : __shared_count(__refs),
3717          __shared_weak_owners_(__refs) {}
3718protected:
3719    virtual ~__shared_weak_count();
3720
3721public:
3722    void __add_shared() _NOEXCEPT;
3723    void __add_weak() _NOEXCEPT;
3724    void __release_shared() _NOEXCEPT;
3725    void __release_weak() _NOEXCEPT;
3726    _LIBCPP_INLINE_VISIBILITY
3727    long use_count() const _NOEXCEPT {return __shared_count::use_count();}
3728    __shared_weak_count* lock() _NOEXCEPT;
3729
3730    // Define the function out only if we build static libc++ without RTTI.
3731    // Otherwise we may break clients who need to compile their projects with
3732    // -fno-rtti and yet link against a libc++.dylib compiled
3733    // without -fno-rtti.
3734#if !defined(_LIBCPP_NO_RTTI) || !defined(_LIBCPP_BUILD_STATIC)
3735    virtual const void* __get_deleter(const type_info&) const _NOEXCEPT;
3736#endif
3737private:
3738    virtual void __on_zero_shared_weak() _NOEXCEPT = 0;
3739};
3740
3741template <class _Tp, class _Dp, class _Alloc>
3742class __shared_ptr_pointer
3743    : public __shared_weak_count
3744{
3745    __compressed_pair<__compressed_pair<_Tp, _Dp>, _Alloc> __data_;
3746public:
3747    _LIBCPP_INLINE_VISIBILITY
3748    __shared_ptr_pointer(_Tp __p, _Dp __d, _Alloc __a)
3749        :  __data_(__compressed_pair<_Tp, _Dp>(__p, _VSTD::move(__d)), _VSTD::move(__a)) {}
3750
3751#ifndef _LIBCPP_NO_RTTI
3752    virtual const void* __get_deleter(const type_info&) const _NOEXCEPT;
3753#endif
3754
3755private:
3756    virtual void __on_zero_shared() _NOEXCEPT;
3757    virtual void __on_zero_shared_weak() _NOEXCEPT;
3758};
3759
3760#ifndef _LIBCPP_NO_RTTI
3761
3762template <class _Tp, class _Dp, class _Alloc>
3763const void*
3764__shared_ptr_pointer<_Tp, _Dp, _Alloc>::__get_deleter(const type_info& __t) const _NOEXCEPT
3765{
3766    return __t == typeid(_Dp) ? _VSTD::addressof(__data_.first().second()) : 0;
3767}
3768
3769#endif  // _LIBCPP_NO_RTTI
3770
3771template <class _Tp, class _Dp, class _Alloc>
3772void
3773__shared_ptr_pointer<_Tp, _Dp, _Alloc>::__on_zero_shared() _NOEXCEPT
3774{
3775    __data_.first().second()(__data_.first().first());
3776    __data_.first().second().~_Dp();
3777}
3778
3779template <class _Tp, class _Dp, class _Alloc>
3780void
3781__shared_ptr_pointer<_Tp, _Dp, _Alloc>::__on_zero_shared_weak() _NOEXCEPT
3782{
3783    typedef typename __allocator_traits_rebind<_Alloc, __shared_ptr_pointer>::type _Al;
3784    typedef allocator_traits<_Al> _ATraits;
3785    typedef pointer_traits<typename _ATraits::pointer> _PTraits;
3786
3787    _Al __a(__data_.second());
3788    __data_.second().~_Alloc();
3789    __a.deallocate(_PTraits::pointer_to(*this), 1);
3790}
3791
3792template <class _Tp, class _Alloc>
3793class __shared_ptr_emplace
3794    : public __shared_weak_count
3795{
3796    __compressed_pair<_Alloc, _Tp> __data_;
3797public:
3798#ifndef _LIBCPP_HAS_NO_VARIADICS
3799
3800    _LIBCPP_INLINE_VISIBILITY
3801    __shared_ptr_emplace(_Alloc __a)
3802        :  __data_(_VSTD::move(__a)) {}
3803
3804    template <class ..._Args>
3805        _LIBCPP_INLINE_VISIBILITY
3806        __shared_ptr_emplace(_Alloc __a, _Args&& ...__args)
3807            :  __data_(piecewise_construct, _VSTD::forward_as_tuple(__a),
3808                   _VSTD::forward_as_tuple(_VSTD::forward<_Args>(__args)...)) {}
3809
3810#else  // _LIBCPP_HAS_NO_VARIADICS
3811
3812    _LIBCPP_INLINE_VISIBILITY
3813    __shared_ptr_emplace(_Alloc __a)
3814        :  __data_(__a) {}
3815
3816    template <class _A0>
3817        _LIBCPP_INLINE_VISIBILITY
3818        __shared_ptr_emplace(_Alloc __a, _A0& __a0)
3819            :  __data_(__a, _Tp(__a0)) {}
3820
3821    template <class _A0, class _A1>
3822        _LIBCPP_INLINE_VISIBILITY
3823        __shared_ptr_emplace(_Alloc __a, _A0& __a0, _A1& __a1)
3824            :  __data_(__a, _Tp(__a0, __a1)) {}
3825
3826    template <class _A0, class _A1, class _A2>
3827        _LIBCPP_INLINE_VISIBILITY
3828        __shared_ptr_emplace(_Alloc __a, _A0& __a0, _A1& __a1, _A2& __a2)
3829            :  __data_(__a, _Tp(__a0, __a1, __a2)) {}
3830
3831#endif  // _LIBCPP_HAS_NO_VARIADICS
3832
3833private:
3834    virtual void __on_zero_shared() _NOEXCEPT;
3835    virtual void __on_zero_shared_weak() _NOEXCEPT;
3836public:
3837    _LIBCPP_INLINE_VISIBILITY
3838    _Tp* get() _NOEXCEPT {return &__data_.second();}
3839};
3840
3841template <class _Tp, class _Alloc>
3842void
3843__shared_ptr_emplace<_Tp, _Alloc>::__on_zero_shared() _NOEXCEPT
3844{
3845    __data_.second().~_Tp();
3846}
3847
3848template <class _Tp, class _Alloc>
3849void
3850__shared_ptr_emplace<_Tp, _Alloc>::__on_zero_shared_weak() _NOEXCEPT
3851{
3852    typedef typename __allocator_traits_rebind<_Alloc, __shared_ptr_emplace>::type _Al;
3853    typedef allocator_traits<_Al> _ATraits;
3854    typedef pointer_traits<typename _ATraits::pointer> _PTraits;
3855    _Al __a(__data_.first());
3856    __data_.first().~_Alloc();
3857    __a.deallocate(_PTraits::pointer_to(*this), 1);
3858}
3859
3860template<class _Tp> class _LIBCPP_TYPE_VIS_ONLY enable_shared_from_this;
3861
3862template<class _Tp>
3863class _LIBCPP_TYPE_VIS_ONLY shared_ptr
3864{
3865public:
3866    typedef _Tp element_type;
3867#if _LIBCPP_STD_VER > 14
3868    typedef weak_ptr<_Tp> weak_type;
3869#endif
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        _LIBCPP_INLINE_VISIBILITY
3982        typename enable_if
3983        <
3984            !is_array<_Yp>::value &&
3985            is_convertible<_Yp*, element_type*>::value,
3986            shared_ptr
3987        >::type&
3988        operator=(auto_ptr<_Yp>&& __r);
3989#else  // _LIBCPP_HAS_NO_RVALUE_REFERENCES
3990    template<class _Yp>
3991        _LIBCPP_INLINE_VISIBILITY
3992        typename enable_if
3993        <
3994            !is_array<_Yp>::value &&
3995            is_convertible<_Yp*, element_type*>::value,
3996            shared_ptr&
3997        >::type
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, class _OrigPtr>
4123        _LIBCPP_INLINE_VISIBILITY
4124        void
4125        __enable_weak_this(const enable_shared_from_this<_Yp>* __e,
4126                           _OrigPtr* __ptr) _NOEXCEPT
4127        {
4128            typedef typename remove_cv<_Yp>::type _RawYp;
4129            if (__e && __e->__weak_this_.expired())
4130            {
4131                __e->__weak_this_ = shared_ptr<_RawYp>(*this,
4132                    const_cast<_RawYp*>(static_cast<const _Yp*>(__ptr)));
4133            }
4134        }
4135
4136    _LIBCPP_INLINE_VISIBILITY
4137    void __enable_weak_this(const volatile void*, const volatile void*) _NOEXCEPT {}
4138
4139    template <class _Up> friend class _LIBCPP_TYPE_VIS_ONLY shared_ptr;
4140    template <class _Up> friend class _LIBCPP_TYPE_VIS_ONLY weak_ptr;
4141};
4142
4143template<class _Tp>
4144inline
4145_LIBCPP_CONSTEXPR
4146shared_ptr<_Tp>::shared_ptr() _NOEXCEPT
4147    : __ptr_(0),
4148      __cntrl_(0)
4149{
4150}
4151
4152template<class _Tp>
4153inline
4154_LIBCPP_CONSTEXPR
4155shared_ptr<_Tp>::shared_ptr(nullptr_t) _NOEXCEPT
4156    : __ptr_(0),
4157      __cntrl_(0)
4158{
4159}
4160
4161template<class _Tp>
4162template<class _Yp>
4163shared_ptr<_Tp>::shared_ptr(_Yp* __p,
4164                            typename enable_if<is_convertible<_Yp*, element_type*>::value, __nat>::type)
4165    : __ptr_(__p)
4166{
4167    unique_ptr<_Yp> __hold(__p);
4168    typedef __shared_ptr_pointer<_Yp*, default_delete<_Yp>, allocator<_Yp> > _CntrlBlk;
4169    __cntrl_ = new _CntrlBlk(__p, default_delete<_Yp>(), allocator<_Yp>());
4170    __hold.release();
4171    __enable_weak_this(__p, __p);
4172}
4173
4174template<class _Tp>
4175template<class _Yp, class _Dp>
4176shared_ptr<_Tp>::shared_ptr(_Yp* __p, _Dp __d,
4177                            typename enable_if<is_convertible<_Yp*, element_type*>::value, __nat>::type)
4178    : __ptr_(__p)
4179{
4180#ifndef _LIBCPP_NO_EXCEPTIONS
4181    try
4182    {
4183#endif  // _LIBCPP_NO_EXCEPTIONS
4184        typedef __shared_ptr_pointer<_Yp*, _Dp, allocator<_Yp> > _CntrlBlk;
4185        __cntrl_ = new _CntrlBlk(__p, __d, allocator<_Yp>());
4186        __enable_weak_this(__p, __p);
4187#ifndef _LIBCPP_NO_EXCEPTIONS
4188    }
4189    catch (...)
4190    {
4191        __d(__p);
4192        throw;
4193    }
4194#endif  // _LIBCPP_NO_EXCEPTIONS
4195}
4196
4197template<class _Tp>
4198template<class _Dp>
4199shared_ptr<_Tp>::shared_ptr(nullptr_t __p, _Dp __d)
4200    : __ptr_(0)
4201{
4202#ifndef _LIBCPP_NO_EXCEPTIONS
4203    try
4204    {
4205#endif  // _LIBCPP_NO_EXCEPTIONS
4206        typedef __shared_ptr_pointer<nullptr_t, _Dp, allocator<_Tp> > _CntrlBlk;
4207        __cntrl_ = new _CntrlBlk(__p, __d, allocator<_Tp>());
4208#ifndef _LIBCPP_NO_EXCEPTIONS
4209    }
4210    catch (...)
4211    {
4212        __d(__p);
4213        throw;
4214    }
4215#endif  // _LIBCPP_NO_EXCEPTIONS
4216}
4217
4218template<class _Tp>
4219template<class _Yp, class _Dp, class _Alloc>
4220shared_ptr<_Tp>::shared_ptr(_Yp* __p, _Dp __d, _Alloc __a,
4221                            typename enable_if<is_convertible<_Yp*, element_type*>::value, __nat>::type)
4222    : __ptr_(__p)
4223{
4224#ifndef _LIBCPP_NO_EXCEPTIONS
4225    try
4226    {
4227#endif  // _LIBCPP_NO_EXCEPTIONS
4228        typedef __shared_ptr_pointer<_Yp*, _Dp, _Alloc> _CntrlBlk;
4229        typedef typename __allocator_traits_rebind<_Alloc, _CntrlBlk>::type _A2;
4230        typedef __allocator_destructor<_A2> _D2;
4231        _A2 __a2(__a);
4232        unique_ptr<_CntrlBlk, _D2> __hold2(__a2.allocate(1), _D2(__a2, 1));
4233        ::new(static_cast<void*>(_VSTD::addressof(*__hold2.get())))
4234            _CntrlBlk(__p, __d, __a);
4235        __cntrl_ = _VSTD::addressof(*__hold2.release());
4236        __enable_weak_this(__p, __p);
4237#ifndef _LIBCPP_NO_EXCEPTIONS
4238    }
4239    catch (...)
4240    {
4241        __d(__p);
4242        throw;
4243    }
4244#endif  // _LIBCPP_NO_EXCEPTIONS
4245}
4246
4247template<class _Tp>
4248template<class _Dp, class _Alloc>
4249shared_ptr<_Tp>::shared_ptr(nullptr_t __p, _Dp __d, _Alloc __a)
4250    : __ptr_(0)
4251{
4252#ifndef _LIBCPP_NO_EXCEPTIONS
4253    try
4254    {
4255#endif  // _LIBCPP_NO_EXCEPTIONS
4256        typedef __shared_ptr_pointer<nullptr_t, _Dp, _Alloc> _CntrlBlk;
4257        typedef typename __allocator_traits_rebind<_Alloc, _CntrlBlk>::type _A2;
4258        typedef __allocator_destructor<_A2> _D2;
4259        _A2 __a2(__a);
4260        unique_ptr<_CntrlBlk, _D2> __hold2(__a2.allocate(1), _D2(__a2, 1));
4261        ::new(static_cast<void*>(_VSTD::addressof(*__hold2.get())))
4262            _CntrlBlk(__p, __d, __a);
4263        __cntrl_ = _VSTD::addressof(*__hold2.release());
4264#ifndef _LIBCPP_NO_EXCEPTIONS
4265    }
4266    catch (...)
4267    {
4268        __d(__p);
4269        throw;
4270    }
4271#endif  // _LIBCPP_NO_EXCEPTIONS
4272}
4273
4274template<class _Tp>
4275template<class _Yp>
4276inline
4277shared_ptr<_Tp>::shared_ptr(const shared_ptr<_Yp>& __r, element_type *__p) _NOEXCEPT
4278    : __ptr_(__p),
4279      __cntrl_(__r.__cntrl_)
4280{
4281    if (__cntrl_)
4282        __cntrl_->__add_shared();
4283}
4284
4285template<class _Tp>
4286inline
4287shared_ptr<_Tp>::shared_ptr(const shared_ptr& __r) _NOEXCEPT
4288    : __ptr_(__r.__ptr_),
4289      __cntrl_(__r.__cntrl_)
4290{
4291    if (__cntrl_)
4292        __cntrl_->__add_shared();
4293}
4294
4295template<class _Tp>
4296template<class _Yp>
4297inline
4298shared_ptr<_Tp>::shared_ptr(const shared_ptr<_Yp>& __r,
4299                            typename enable_if<is_convertible<_Yp*, _Tp*>::value, __nat>::type)
4300         _NOEXCEPT
4301    : __ptr_(__r.__ptr_),
4302      __cntrl_(__r.__cntrl_)
4303{
4304    if (__cntrl_)
4305        __cntrl_->__add_shared();
4306}
4307
4308#ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES
4309
4310template<class _Tp>
4311inline
4312shared_ptr<_Tp>::shared_ptr(shared_ptr&& __r) _NOEXCEPT
4313    : __ptr_(__r.__ptr_),
4314      __cntrl_(__r.__cntrl_)
4315{
4316    __r.__ptr_ = 0;
4317    __r.__cntrl_ = 0;
4318}
4319
4320template<class _Tp>
4321template<class _Yp>
4322inline
4323shared_ptr<_Tp>::shared_ptr(shared_ptr<_Yp>&& __r,
4324                            typename enable_if<is_convertible<_Yp*, _Tp*>::value, __nat>::type)
4325         _NOEXCEPT
4326    : __ptr_(__r.__ptr_),
4327      __cntrl_(__r.__cntrl_)
4328{
4329    __r.__ptr_ = 0;
4330    __r.__cntrl_ = 0;
4331}
4332
4333#endif  // _LIBCPP_HAS_NO_RVALUE_REFERENCES
4334
4335template<class _Tp>
4336template<class _Yp>
4337#ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES
4338shared_ptr<_Tp>::shared_ptr(auto_ptr<_Yp>&& __r,
4339#else
4340shared_ptr<_Tp>::shared_ptr(auto_ptr<_Yp> __r,
4341#endif
4342                            typename enable_if<is_convertible<_Yp*, element_type*>::value, __nat>::type)
4343    : __ptr_(__r.get())
4344{
4345    typedef __shared_ptr_pointer<_Yp*, default_delete<_Yp>, allocator<_Yp> > _CntrlBlk;
4346    __cntrl_ = new _CntrlBlk(__r.get(), default_delete<_Yp>(), allocator<_Yp>());
4347    __enable_weak_this(__r.get(), __r.get());
4348    __r.release();
4349}
4350
4351template<class _Tp>
4352template <class _Yp, class _Dp>
4353#ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES
4354shared_ptr<_Tp>::shared_ptr(unique_ptr<_Yp, _Dp>&& __r,
4355#else
4356shared_ptr<_Tp>::shared_ptr(unique_ptr<_Yp, _Dp> __r,
4357#endif
4358                            typename enable_if
4359                            <
4360                                !is_lvalue_reference<_Dp>::value &&
4361                                !is_array<_Yp>::value &&
4362                                is_convertible<typename unique_ptr<_Yp, _Dp>::pointer, element_type*>::value,
4363                                __nat
4364                            >::type)
4365    : __ptr_(__r.get())
4366{
4367#if _LIBCPP_STD_VER > 11
4368    if (__ptr_ == nullptr)
4369        __cntrl_ = nullptr;
4370    else
4371#endif
4372    {
4373        typedef __shared_ptr_pointer<_Yp*, _Dp, allocator<_Yp> > _CntrlBlk;
4374        __cntrl_ = new _CntrlBlk(__r.get(), __r.get_deleter(), allocator<_Yp>());
4375        __enable_weak_this(__r.get(), __r.get());
4376    }
4377    __r.release();
4378}
4379
4380template<class _Tp>
4381template <class _Yp, class _Dp>
4382#ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES
4383shared_ptr<_Tp>::shared_ptr(unique_ptr<_Yp, _Dp>&& __r,
4384#else
4385shared_ptr<_Tp>::shared_ptr(unique_ptr<_Yp, _Dp> __r,
4386#endif
4387                            typename enable_if
4388                            <
4389                                is_lvalue_reference<_Dp>::value &&
4390                                !is_array<_Yp>::value &&
4391                                is_convertible<typename unique_ptr<_Yp, _Dp>::pointer, element_type*>::value,
4392                                __nat
4393                            >::type)
4394    : __ptr_(__r.get())
4395{
4396#if _LIBCPP_STD_VER > 11
4397    if (__ptr_ == nullptr)
4398        __cntrl_ = nullptr;
4399    else
4400#endif
4401    {
4402        typedef __shared_ptr_pointer<_Yp*,
4403                                     reference_wrapper<typename remove_reference<_Dp>::type>,
4404                                     allocator<_Yp> > _CntrlBlk;
4405        __cntrl_ = new _CntrlBlk(__r.get(), ref(__r.get_deleter()), allocator<_Yp>());
4406        __enable_weak_this(__r.get(), __r.get());
4407    }
4408    __r.release();
4409}
4410
4411#ifndef _LIBCPP_HAS_NO_VARIADICS
4412
4413template<class _Tp>
4414template<class ..._Args>
4415shared_ptr<_Tp>
4416shared_ptr<_Tp>::make_shared(_Args&& ...__args)
4417{
4418    typedef __shared_ptr_emplace<_Tp, allocator<_Tp> > _CntrlBlk;
4419    typedef allocator<_CntrlBlk> _A2;
4420    typedef __allocator_destructor<_A2> _D2;
4421    _A2 __a2;
4422    unique_ptr<_CntrlBlk, _D2> __hold2(__a2.allocate(1), _D2(__a2, 1));
4423    ::new(__hold2.get()) _CntrlBlk(__a2, _VSTD::forward<_Args>(__args)...);
4424    shared_ptr<_Tp> __r;
4425    __r.__ptr_ = __hold2.get()->get();
4426    __r.__cntrl_ = __hold2.release();
4427    __r.__enable_weak_this(__r.__ptr_, __r.__ptr_);
4428    return __r;
4429}
4430
4431template<class _Tp>
4432template<class _Alloc, class ..._Args>
4433shared_ptr<_Tp>
4434shared_ptr<_Tp>::allocate_shared(const _Alloc& __a, _Args&& ...__args)
4435{
4436    typedef __shared_ptr_emplace<_Tp, _Alloc> _CntrlBlk;
4437    typedef typename __allocator_traits_rebind<_Alloc, _CntrlBlk>::type _A2;
4438    typedef __allocator_destructor<_A2> _D2;
4439    _A2 __a2(__a);
4440    unique_ptr<_CntrlBlk, _D2> __hold2(__a2.allocate(1), _D2(__a2, 1));
4441    ::new(static_cast<void*>(_VSTD::addressof(*__hold2.get())))
4442        _CntrlBlk(__a, _VSTD::forward<_Args>(__args)...);
4443    shared_ptr<_Tp> __r;
4444    __r.__ptr_ = __hold2.get()->get();
4445    __r.__cntrl_ = _VSTD::addressof(*__hold2.release());
4446    __r.__enable_weak_this(__r.__ptr_, __r.__ptr_);
4447    return __r;
4448}
4449
4450#else  // _LIBCPP_HAS_NO_VARIADICS
4451
4452template<class _Tp>
4453shared_ptr<_Tp>
4454shared_ptr<_Tp>::make_shared()
4455{
4456    typedef __shared_ptr_emplace<_Tp, allocator<_Tp> > _CntrlBlk;
4457    typedef allocator<_CntrlBlk> _Alloc2;
4458    typedef __allocator_destructor<_Alloc2> _D2;
4459    _Alloc2 __alloc2;
4460    unique_ptr<_CntrlBlk, _D2> __hold2(__alloc2.allocate(1), _D2(__alloc2, 1));
4461    ::new(__hold2.get()) _CntrlBlk(__alloc2);
4462    shared_ptr<_Tp> __r;
4463    __r.__ptr_ = __hold2.get()->get();
4464    __r.__cntrl_ = __hold2.release();
4465    __r.__enable_weak_this(__r.__ptr_, __r.__ptr_);
4466    return __r;
4467}
4468
4469template<class _Tp>
4470template<class _A0>
4471shared_ptr<_Tp>
4472shared_ptr<_Tp>::make_shared(_A0& __a0)
4473{
4474    typedef __shared_ptr_emplace<_Tp, allocator<_Tp> > _CntrlBlk;
4475    typedef allocator<_CntrlBlk> _Alloc2;
4476    typedef __allocator_destructor<_Alloc2> _D2;
4477    _Alloc2 __alloc2;
4478    unique_ptr<_CntrlBlk, _D2> __hold2(__alloc2.allocate(1), _D2(__alloc2, 1));
4479    ::new(__hold2.get()) _CntrlBlk(__alloc2, __a0);
4480    shared_ptr<_Tp> __r;
4481    __r.__ptr_ = __hold2.get()->get();
4482    __r.__cntrl_ = __hold2.release();
4483    __r.__enable_weak_this(__r.__ptr_, __r.__ptr_);
4484    return __r;
4485}
4486
4487template<class _Tp>
4488template<class _A0, class _A1>
4489shared_ptr<_Tp>
4490shared_ptr<_Tp>::make_shared(_A0& __a0, _A1& __a1)
4491{
4492    typedef __shared_ptr_emplace<_Tp, allocator<_Tp> > _CntrlBlk;
4493    typedef allocator<_CntrlBlk> _Alloc2;
4494    typedef __allocator_destructor<_Alloc2> _D2;
4495    _Alloc2 __alloc2;
4496    unique_ptr<_CntrlBlk, _D2> __hold2(__alloc2.allocate(1), _D2(__alloc2, 1));
4497    ::new(__hold2.get()) _CntrlBlk(__alloc2, __a0, __a1);
4498    shared_ptr<_Tp> __r;
4499    __r.__ptr_ = __hold2.get()->get();
4500    __r.__cntrl_ = __hold2.release();
4501    __r.__enable_weak_this(__r.__ptr_, __r.__ptr_);
4502    return __r;
4503}
4504
4505template<class _Tp>
4506template<class _A0, class _A1, class _A2>
4507shared_ptr<_Tp>
4508shared_ptr<_Tp>::make_shared(_A0& __a0, _A1& __a1, _A2& __a2)
4509{
4510    typedef __shared_ptr_emplace<_Tp, allocator<_Tp> > _CntrlBlk;
4511    typedef allocator<_CntrlBlk> _Alloc2;
4512    typedef __allocator_destructor<_Alloc2> _D2;
4513    _Alloc2 __alloc2;
4514    unique_ptr<_CntrlBlk, _D2> __hold2(__alloc2.allocate(1), _D2(__alloc2, 1));
4515    ::new(__hold2.get()) _CntrlBlk(__alloc2, __a0, __a1, __a2);
4516    shared_ptr<_Tp> __r;
4517    __r.__ptr_ = __hold2.get()->get();
4518    __r.__cntrl_ = __hold2.release();
4519    __r.__enable_weak_this(__r.__ptr_, __r.__ptr_);
4520    return __r;
4521}
4522
4523template<class _Tp>
4524template<class _Alloc>
4525shared_ptr<_Tp>
4526shared_ptr<_Tp>::allocate_shared(const _Alloc& __a)
4527{
4528    typedef __shared_ptr_emplace<_Tp, _Alloc> _CntrlBlk;
4529    typedef typename __allocator_traits_rebind<_Alloc, _CntrlBlk>::type _Alloc2;
4530    typedef __allocator_destructor<_Alloc2> _D2;
4531    _Alloc2 __alloc2(__a);
4532    unique_ptr<_CntrlBlk, _D2> __hold2(__alloc2.allocate(1), _D2(__alloc2, 1));
4533    ::new(static_cast<void*>(_VSTD::addressof(*__hold2.get())))
4534        _CntrlBlk(__a);
4535    shared_ptr<_Tp> __r;
4536    __r.__ptr_ = __hold2.get()->get();
4537    __r.__cntrl_ = _VSTD::addressof(*__hold2.release());
4538    __r.__enable_weak_this(__r.__ptr_, __r.__ptr_);
4539    return __r;
4540}
4541
4542template<class _Tp>
4543template<class _Alloc, class _A0>
4544shared_ptr<_Tp>
4545shared_ptr<_Tp>::allocate_shared(const _Alloc& __a, _A0& __a0)
4546{
4547    typedef __shared_ptr_emplace<_Tp, _Alloc> _CntrlBlk;
4548    typedef typename __allocator_traits_rebind<_Alloc, _CntrlBlk>::type _Alloc2;
4549    typedef __allocator_destructor<_Alloc2> _D2;
4550    _Alloc2 __alloc2(__a);
4551    unique_ptr<_CntrlBlk, _D2> __hold2(__alloc2.allocate(1), _D2(__alloc2, 1));
4552    ::new(static_cast<void*>(_VSTD::addressof(*__hold2.get())))
4553        _CntrlBlk(__a, __a0);
4554    shared_ptr<_Tp> __r;
4555    __r.__ptr_ = __hold2.get()->get();
4556    __r.__cntrl_ = _VSTD::addressof(*__hold2.release());
4557    __r.__enable_weak_this(__r.__ptr_, __r.__ptr_);
4558    return __r;
4559}
4560
4561template<class _Tp>
4562template<class _Alloc, class _A0, class _A1>
4563shared_ptr<_Tp>
4564shared_ptr<_Tp>::allocate_shared(const _Alloc& __a, _A0& __a0, _A1& __a1)
4565{
4566    typedef __shared_ptr_emplace<_Tp, _Alloc> _CntrlBlk;
4567    typedef typename __allocator_traits_rebind<_Alloc, _CntrlBlk>::type _Alloc2;
4568    typedef __allocator_destructor<_Alloc2> _D2;
4569    _Alloc2 __alloc2(__a);
4570    unique_ptr<_CntrlBlk, _D2> __hold2(__alloc2.allocate(1), _D2(__alloc2, 1));
4571    ::new(static_cast<void*>(_VSTD::addressof(*__hold2.get())))
4572        _CntrlBlk(__a, __a0, __a1);
4573    shared_ptr<_Tp> __r;
4574    __r.__ptr_ = __hold2.get()->get();
4575    __r.__cntrl_ = _VSTD::addressof(*__hold2.release());
4576    __r.__enable_weak_this(__r.__ptr_, __r.__ptr_);
4577    return __r;
4578}
4579
4580template<class _Tp>
4581template<class _Alloc, class _A0, class _A1, class _A2>
4582shared_ptr<_Tp>
4583shared_ptr<_Tp>::allocate_shared(const _Alloc& __a, _A0& __a0, _A1& __a1, _A2& __a2)
4584{
4585    typedef __shared_ptr_emplace<_Tp, _Alloc> _CntrlBlk;
4586    typedef typename __allocator_traits_rebind<_Alloc, _CntrlBlk>::type _Alloc2;
4587    typedef __allocator_destructor<_Alloc2> _D2;
4588    _Alloc2 __alloc2(__a);
4589    unique_ptr<_CntrlBlk, _D2> __hold2(__alloc2.allocate(1), _D2(__alloc2, 1));
4590    ::new(static_cast<void*>(_VSTD::addressof(*__hold2.get())))
4591        _CntrlBlk(__a, __a0, __a1, __a2);
4592    shared_ptr<_Tp> __r;
4593    __r.__ptr_ = __hold2.get()->get();
4594    __r.__cntrl_ = _VSTD::addressof(*__hold2.release());
4595    __r.__enable_weak_this(__r.__ptr_, __r.__ptr_);
4596    return __r;
4597}
4598
4599#endif  // _LIBCPP_HAS_NO_VARIADICS
4600
4601template<class _Tp>
4602shared_ptr<_Tp>::~shared_ptr()
4603{
4604    if (__cntrl_)
4605        __cntrl_->__release_shared();
4606}
4607
4608template<class _Tp>
4609inline
4610shared_ptr<_Tp>&
4611shared_ptr<_Tp>::operator=(const shared_ptr& __r) _NOEXCEPT
4612{
4613    shared_ptr(__r).swap(*this);
4614    return *this;
4615}
4616
4617template<class _Tp>
4618template<class _Yp>
4619inline
4620typename enable_if
4621<
4622    is_convertible<_Yp*, _Tp*>::value,
4623    shared_ptr<_Tp>&
4624>::type
4625shared_ptr<_Tp>::operator=(const shared_ptr<_Yp>& __r) _NOEXCEPT
4626{
4627    shared_ptr(__r).swap(*this);
4628    return *this;
4629}
4630
4631#ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES
4632
4633template<class _Tp>
4634inline
4635shared_ptr<_Tp>&
4636shared_ptr<_Tp>::operator=(shared_ptr&& __r) _NOEXCEPT
4637{
4638    shared_ptr(_VSTD::move(__r)).swap(*this);
4639    return *this;
4640}
4641
4642template<class _Tp>
4643template<class _Yp>
4644inline
4645typename enable_if
4646<
4647    is_convertible<_Yp*, _Tp*>::value,
4648    shared_ptr<_Tp>&
4649>::type
4650shared_ptr<_Tp>::operator=(shared_ptr<_Yp>&& __r)
4651{
4652    shared_ptr(_VSTD::move(__r)).swap(*this);
4653    return *this;
4654}
4655
4656template<class _Tp>
4657template<class _Yp>
4658inline
4659typename enable_if
4660<
4661    !is_array<_Yp>::value &&
4662    is_convertible<_Yp*, _Tp*>::value,
4663    shared_ptr<_Tp>
4664>::type&
4665shared_ptr<_Tp>::operator=(auto_ptr<_Yp>&& __r)
4666{
4667    shared_ptr(_VSTD::move(__r)).swap(*this);
4668    return *this;
4669}
4670
4671template<class _Tp>
4672template <class _Yp, class _Dp>
4673inline
4674typename enable_if
4675<
4676    !is_array<_Yp>::value &&
4677    is_convertible<typename unique_ptr<_Yp, _Dp>::pointer, _Tp*>::value,
4678    shared_ptr<_Tp>&
4679>::type
4680shared_ptr<_Tp>::operator=(unique_ptr<_Yp, _Dp>&& __r)
4681{
4682    shared_ptr(_VSTD::move(__r)).swap(*this);
4683    return *this;
4684}
4685
4686#else  // _LIBCPP_HAS_NO_RVALUE_REFERENCES
4687
4688template<class _Tp>
4689template<class _Yp>
4690inline _LIBCPP_INLINE_VISIBILITY
4691typename enable_if
4692<
4693    !is_array<_Yp>::value &&
4694    is_convertible<_Yp*, _Tp*>::value,
4695    shared_ptr<_Tp>&
4696>::type
4697shared_ptr<_Tp>::operator=(auto_ptr<_Yp> __r)
4698{
4699    shared_ptr(__r).swap(*this);
4700    return *this;
4701}
4702
4703template<class _Tp>
4704template <class _Yp, class _Dp>
4705inline _LIBCPP_INLINE_VISIBILITY
4706typename enable_if
4707<
4708    !is_array<_Yp>::value &&
4709    is_convertible<typename unique_ptr<_Yp, _Dp>::pointer, _Tp*>::value,
4710    shared_ptr<_Tp>&
4711>::type
4712shared_ptr<_Tp>::operator=(unique_ptr<_Yp, _Dp> __r)
4713{
4714    shared_ptr(_VSTD::move(__r)).swap(*this);
4715    return *this;
4716}
4717
4718#endif  // _LIBCPP_HAS_NO_RVALUE_REFERENCES
4719
4720template<class _Tp>
4721inline
4722void
4723shared_ptr<_Tp>::swap(shared_ptr& __r) _NOEXCEPT
4724{
4725    _VSTD::swap(__ptr_, __r.__ptr_);
4726    _VSTD::swap(__cntrl_, __r.__cntrl_);
4727}
4728
4729template<class _Tp>
4730inline
4731void
4732shared_ptr<_Tp>::reset() _NOEXCEPT
4733{
4734    shared_ptr().swap(*this);
4735}
4736
4737template<class _Tp>
4738template<class _Yp>
4739inline
4740typename enable_if
4741<
4742    is_convertible<_Yp*, _Tp*>::value,
4743    void
4744>::type
4745shared_ptr<_Tp>::reset(_Yp* __p)
4746{
4747    shared_ptr(__p).swap(*this);
4748}
4749
4750template<class _Tp>
4751template<class _Yp, class _Dp>
4752inline
4753typename enable_if
4754<
4755    is_convertible<_Yp*, _Tp*>::value,
4756    void
4757>::type
4758shared_ptr<_Tp>::reset(_Yp* __p, _Dp __d)
4759{
4760    shared_ptr(__p, __d).swap(*this);
4761}
4762
4763template<class _Tp>
4764template<class _Yp, class _Dp, class _Alloc>
4765inline
4766typename enable_if
4767<
4768    is_convertible<_Yp*, _Tp*>::value,
4769    void
4770>::type
4771shared_ptr<_Tp>::reset(_Yp* __p, _Dp __d, _Alloc __a)
4772{
4773    shared_ptr(__p, __d, __a).swap(*this);
4774}
4775
4776#ifndef _LIBCPP_HAS_NO_VARIADICS
4777
4778template<class _Tp, class ..._Args>
4779inline _LIBCPP_INLINE_VISIBILITY
4780typename enable_if
4781<
4782    !is_array<_Tp>::value,
4783    shared_ptr<_Tp>
4784>::type
4785make_shared(_Args&& ...__args)
4786{
4787    return shared_ptr<_Tp>::make_shared(_VSTD::forward<_Args>(__args)...);
4788}
4789
4790template<class _Tp, class _Alloc, class ..._Args>
4791inline _LIBCPP_INLINE_VISIBILITY
4792typename enable_if
4793<
4794    !is_array<_Tp>::value,
4795    shared_ptr<_Tp>
4796>::type
4797allocate_shared(const _Alloc& __a, _Args&& ...__args)
4798{
4799    return shared_ptr<_Tp>::allocate_shared(__a, _VSTD::forward<_Args>(__args)...);
4800}
4801
4802#else  // _LIBCPP_HAS_NO_VARIADICS
4803
4804template<class _Tp>
4805inline _LIBCPP_INLINE_VISIBILITY
4806shared_ptr<_Tp>
4807make_shared()
4808{
4809    return shared_ptr<_Tp>::make_shared();
4810}
4811
4812template<class _Tp, class _A0>
4813inline _LIBCPP_INLINE_VISIBILITY
4814shared_ptr<_Tp>
4815make_shared(_A0& __a0)
4816{
4817    return shared_ptr<_Tp>::make_shared(__a0);
4818}
4819
4820template<class _Tp, class _A0, class _A1>
4821inline _LIBCPP_INLINE_VISIBILITY
4822shared_ptr<_Tp>
4823make_shared(_A0& __a0, _A1& __a1)
4824{
4825    return shared_ptr<_Tp>::make_shared(__a0, __a1);
4826}
4827
4828template<class _Tp, class _A0, class _A1, class _A2>
4829inline _LIBCPP_INLINE_VISIBILITY
4830shared_ptr<_Tp>
4831make_shared(_A0& __a0, _A1& __a1, _A2& __a2)
4832{
4833    return shared_ptr<_Tp>::make_shared(__a0, __a1, __a2);
4834}
4835
4836template<class _Tp, class _Alloc>
4837inline _LIBCPP_INLINE_VISIBILITY
4838shared_ptr<_Tp>
4839allocate_shared(const _Alloc& __a)
4840{
4841    return shared_ptr<_Tp>::allocate_shared(__a);
4842}
4843
4844template<class _Tp, class _Alloc, class _A0>
4845inline _LIBCPP_INLINE_VISIBILITY
4846shared_ptr<_Tp>
4847allocate_shared(const _Alloc& __a, _A0& __a0)
4848{
4849    return shared_ptr<_Tp>::allocate_shared(__a, __a0);
4850}
4851
4852template<class _Tp, class _Alloc, class _A0, class _A1>
4853inline _LIBCPP_INLINE_VISIBILITY
4854shared_ptr<_Tp>
4855allocate_shared(const _Alloc& __a, _A0& __a0, _A1& __a1)
4856{
4857    return shared_ptr<_Tp>::allocate_shared(__a, __a0, __a1);
4858}
4859
4860template<class _Tp, class _Alloc, class _A0, class _A1, class _A2>
4861inline _LIBCPP_INLINE_VISIBILITY
4862shared_ptr<_Tp>
4863allocate_shared(const _Alloc& __a, _A0& __a0, _A1& __a1, _A2& __a2)
4864{
4865    return shared_ptr<_Tp>::allocate_shared(__a, __a0, __a1, __a2);
4866}
4867
4868#endif  // _LIBCPP_HAS_NO_VARIADICS
4869
4870template<class _Tp, class _Up>
4871inline _LIBCPP_INLINE_VISIBILITY
4872bool
4873operator==(const shared_ptr<_Tp>& __x, const shared_ptr<_Up>& __y) _NOEXCEPT
4874{
4875    return __x.get() == __y.get();
4876}
4877
4878template<class _Tp, class _Up>
4879inline _LIBCPP_INLINE_VISIBILITY
4880bool
4881operator!=(const shared_ptr<_Tp>& __x, const shared_ptr<_Up>& __y) _NOEXCEPT
4882{
4883    return !(__x == __y);
4884}
4885
4886template<class _Tp, class _Up>
4887inline _LIBCPP_INLINE_VISIBILITY
4888bool
4889operator<(const shared_ptr<_Tp>& __x, const shared_ptr<_Up>& __y) _NOEXCEPT
4890{
4891    typedef typename common_type<_Tp*, _Up*>::type _Vp;
4892    return less<_Vp>()(__x.get(), __y.get());
4893}
4894
4895template<class _Tp, class _Up>
4896inline _LIBCPP_INLINE_VISIBILITY
4897bool
4898operator>(const shared_ptr<_Tp>& __x, const shared_ptr<_Up>& __y) _NOEXCEPT
4899{
4900    return __y < __x;
4901}
4902
4903template<class _Tp, class _Up>
4904inline _LIBCPP_INLINE_VISIBILITY
4905bool
4906operator<=(const shared_ptr<_Tp>& __x, const shared_ptr<_Up>& __y) _NOEXCEPT
4907{
4908    return !(__y < __x);
4909}
4910
4911template<class _Tp, class _Up>
4912inline _LIBCPP_INLINE_VISIBILITY
4913bool
4914operator>=(const shared_ptr<_Tp>& __x, const shared_ptr<_Up>& __y) _NOEXCEPT
4915{
4916    return !(__x < __y);
4917}
4918
4919template<class _Tp>
4920inline _LIBCPP_INLINE_VISIBILITY
4921bool
4922operator==(const shared_ptr<_Tp>& __x, nullptr_t) _NOEXCEPT
4923{
4924    return !__x;
4925}
4926
4927template<class _Tp>
4928inline _LIBCPP_INLINE_VISIBILITY
4929bool
4930operator==(nullptr_t, const shared_ptr<_Tp>& __x) _NOEXCEPT
4931{
4932    return !__x;
4933}
4934
4935template<class _Tp>
4936inline _LIBCPP_INLINE_VISIBILITY
4937bool
4938operator!=(const shared_ptr<_Tp>& __x, nullptr_t) _NOEXCEPT
4939{
4940    return static_cast<bool>(__x);
4941}
4942
4943template<class _Tp>
4944inline _LIBCPP_INLINE_VISIBILITY
4945bool
4946operator!=(nullptr_t, const shared_ptr<_Tp>& __x) _NOEXCEPT
4947{
4948    return static_cast<bool>(__x);
4949}
4950
4951template<class _Tp>
4952inline _LIBCPP_INLINE_VISIBILITY
4953bool
4954operator<(const shared_ptr<_Tp>& __x, nullptr_t) _NOEXCEPT
4955{
4956    return less<_Tp*>()(__x.get(), nullptr);
4957}
4958
4959template<class _Tp>
4960inline _LIBCPP_INLINE_VISIBILITY
4961bool
4962operator<(nullptr_t, const shared_ptr<_Tp>& __x) _NOEXCEPT
4963{
4964    return less<_Tp*>()(nullptr, __x.get());
4965}
4966
4967template<class _Tp>
4968inline _LIBCPP_INLINE_VISIBILITY
4969bool
4970operator>(const shared_ptr<_Tp>& __x, nullptr_t) _NOEXCEPT
4971{
4972    return nullptr < __x;
4973}
4974
4975template<class _Tp>
4976inline _LIBCPP_INLINE_VISIBILITY
4977bool
4978operator>(nullptr_t, const shared_ptr<_Tp>& __x) _NOEXCEPT
4979{
4980    return __x < nullptr;
4981}
4982
4983template<class _Tp>
4984inline _LIBCPP_INLINE_VISIBILITY
4985bool
4986operator<=(const shared_ptr<_Tp>& __x, nullptr_t) _NOEXCEPT
4987{
4988    return !(nullptr < __x);
4989}
4990
4991template<class _Tp>
4992inline _LIBCPP_INLINE_VISIBILITY
4993bool
4994operator<=(nullptr_t, const shared_ptr<_Tp>& __x) _NOEXCEPT
4995{
4996    return !(__x < nullptr);
4997}
4998
4999template<class _Tp>
5000inline _LIBCPP_INLINE_VISIBILITY
5001bool
5002operator>=(const shared_ptr<_Tp>& __x, nullptr_t) _NOEXCEPT
5003{
5004    return !(__x < nullptr);
5005}
5006
5007template<class _Tp>
5008inline _LIBCPP_INLINE_VISIBILITY
5009bool
5010operator>=(nullptr_t, const shared_ptr<_Tp>& __x) _NOEXCEPT
5011{
5012    return !(nullptr < __x);
5013}
5014
5015template<class _Tp>
5016inline _LIBCPP_INLINE_VISIBILITY
5017void
5018swap(shared_ptr<_Tp>& __x, shared_ptr<_Tp>& __y) _NOEXCEPT
5019{
5020    __x.swap(__y);
5021}
5022
5023template<class _Tp, class _Up>
5024inline _LIBCPP_INLINE_VISIBILITY
5025typename enable_if
5026<
5027    !is_array<_Tp>::value && !is_array<_Up>::value,
5028    shared_ptr<_Tp>
5029>::type
5030static_pointer_cast(const shared_ptr<_Up>& __r) _NOEXCEPT
5031{
5032    return shared_ptr<_Tp>(__r, static_cast<_Tp*>(__r.get()));
5033}
5034
5035template<class _Tp, class _Up>
5036inline _LIBCPP_INLINE_VISIBILITY
5037typename enable_if
5038<
5039    !is_array<_Tp>::value && !is_array<_Up>::value,
5040    shared_ptr<_Tp>
5041>::type
5042dynamic_pointer_cast(const shared_ptr<_Up>& __r) _NOEXCEPT
5043{
5044    _Tp* __p = dynamic_cast<_Tp*>(__r.get());
5045    return __p ? shared_ptr<_Tp>(__r, __p) : shared_ptr<_Tp>();
5046}
5047
5048template<class _Tp, class _Up>
5049typename enable_if
5050<
5051    is_array<_Tp>::value == is_array<_Up>::value,
5052    shared_ptr<_Tp>
5053>::type
5054const_pointer_cast(const shared_ptr<_Up>& __r) _NOEXCEPT
5055{
5056    typedef typename remove_extent<_Tp>::type _RTp;
5057    return shared_ptr<_Tp>(__r, const_cast<_RTp*>(__r.get()));
5058}
5059
5060#ifndef _LIBCPP_NO_RTTI
5061
5062template<class _Dp, class _Tp>
5063inline _LIBCPP_INLINE_VISIBILITY
5064_Dp*
5065get_deleter(const shared_ptr<_Tp>& __p) _NOEXCEPT
5066{
5067    return __p.template __get_deleter<_Dp>();
5068}
5069
5070#endif  // _LIBCPP_NO_RTTI
5071
5072template<class _Tp>
5073class _LIBCPP_TYPE_VIS_ONLY weak_ptr
5074{
5075public:
5076    typedef _Tp element_type;
5077private:
5078    element_type*        __ptr_;
5079    __shared_weak_count* __cntrl_;
5080
5081public:
5082    _LIBCPP_INLINE_VISIBILITY
5083    _LIBCPP_CONSTEXPR weak_ptr() _NOEXCEPT;
5084    template<class _Yp> _LIBCPP_INLINE_VISIBILITY weak_ptr(shared_ptr<_Yp> const& __r,
5085                   typename enable_if<is_convertible<_Yp*, _Tp*>::value, __nat*>::type = 0)
5086                        _NOEXCEPT;
5087    _LIBCPP_INLINE_VISIBILITY
5088    weak_ptr(weak_ptr const& __r) _NOEXCEPT;
5089    template<class _Yp> _LIBCPP_INLINE_VISIBILITY weak_ptr(weak_ptr<_Yp> const& __r,
5090                   typename enable_if<is_convertible<_Yp*, _Tp*>::value, __nat*>::type = 0)
5091                         _NOEXCEPT;
5092
5093#ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES
5094    _LIBCPP_INLINE_VISIBILITY
5095    weak_ptr(weak_ptr&& __r) _NOEXCEPT;
5096    template<class _Yp> _LIBCPP_INLINE_VISIBILITY weak_ptr(weak_ptr<_Yp>&& __r,
5097                   typename enable_if<is_convertible<_Yp*, _Tp*>::value, __nat*>::type = 0)
5098                         _NOEXCEPT;
5099#endif  // _LIBCPP_HAS_NO_RVALUE_REFERENCES
5100    ~weak_ptr();
5101
5102    _LIBCPP_INLINE_VISIBILITY
5103    weak_ptr& operator=(weak_ptr const& __r) _NOEXCEPT;
5104    template<class _Yp>
5105        typename enable_if
5106        <
5107            is_convertible<_Yp*, element_type*>::value,
5108            weak_ptr&
5109        >::type
5110        _LIBCPP_INLINE_VISIBILITY
5111        operator=(weak_ptr<_Yp> const& __r) _NOEXCEPT;
5112
5113#ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES
5114
5115    _LIBCPP_INLINE_VISIBILITY
5116    weak_ptr& operator=(weak_ptr&& __r) _NOEXCEPT;
5117    template<class _Yp>
5118        typename enable_if
5119        <
5120            is_convertible<_Yp*, element_type*>::value,
5121            weak_ptr&
5122        >::type
5123        _LIBCPP_INLINE_VISIBILITY
5124        operator=(weak_ptr<_Yp>&& __r) _NOEXCEPT;
5125
5126#endif  // _LIBCPP_HAS_NO_RVALUE_REFERENCES
5127
5128    template<class _Yp>
5129        typename enable_if
5130        <
5131            is_convertible<_Yp*, element_type*>::value,
5132            weak_ptr&
5133        >::type
5134        _LIBCPP_INLINE_VISIBILITY
5135        operator=(shared_ptr<_Yp> const& __r) _NOEXCEPT;
5136
5137    _LIBCPP_INLINE_VISIBILITY
5138    void swap(weak_ptr& __r) _NOEXCEPT;
5139    _LIBCPP_INLINE_VISIBILITY
5140    void reset() _NOEXCEPT;
5141
5142    _LIBCPP_INLINE_VISIBILITY
5143    long use_count() const _NOEXCEPT
5144        {return __cntrl_ ? __cntrl_->use_count() : 0;}
5145    _LIBCPP_INLINE_VISIBILITY
5146    bool expired() const _NOEXCEPT
5147        {return __cntrl_ == 0 || __cntrl_->use_count() == 0;}
5148    shared_ptr<_Tp> lock() const _NOEXCEPT;
5149    template<class _Up>
5150        _LIBCPP_INLINE_VISIBILITY
5151        bool owner_before(const shared_ptr<_Up>& __r) const
5152        {return __cntrl_ < __r.__cntrl_;}
5153    template<class _Up>
5154        _LIBCPP_INLINE_VISIBILITY
5155        bool owner_before(const weak_ptr<_Up>& __r) const
5156        {return __cntrl_ < __r.__cntrl_;}
5157
5158    template <class _Up> friend class _LIBCPP_TYPE_VIS_ONLY weak_ptr;
5159    template <class _Up> friend class _LIBCPP_TYPE_VIS_ONLY shared_ptr;
5160};
5161
5162template<class _Tp>
5163inline
5164_LIBCPP_CONSTEXPR
5165weak_ptr<_Tp>::weak_ptr() _NOEXCEPT
5166    : __ptr_(0),
5167      __cntrl_(0)
5168{
5169}
5170
5171template<class _Tp>
5172inline
5173weak_ptr<_Tp>::weak_ptr(weak_ptr const& __r) _NOEXCEPT
5174    : __ptr_(__r.__ptr_),
5175      __cntrl_(__r.__cntrl_)
5176{
5177    if (__cntrl_)
5178        __cntrl_->__add_weak();
5179}
5180
5181template<class _Tp>
5182template<class _Yp>
5183inline
5184weak_ptr<_Tp>::weak_ptr(shared_ptr<_Yp> const& __r,
5185                        typename enable_if<is_convertible<_Yp*, _Tp*>::value, __nat*>::type)
5186                         _NOEXCEPT
5187    : __ptr_(__r.__ptr_),
5188      __cntrl_(__r.__cntrl_)
5189{
5190    if (__cntrl_)
5191        __cntrl_->__add_weak();
5192}
5193
5194template<class _Tp>
5195template<class _Yp>
5196inline
5197weak_ptr<_Tp>::weak_ptr(weak_ptr<_Yp> const& __r,
5198                        typename enable_if<is_convertible<_Yp*, _Tp*>::value, __nat*>::type)
5199         _NOEXCEPT
5200    : __ptr_(__r.__ptr_),
5201      __cntrl_(__r.__cntrl_)
5202{
5203    if (__cntrl_)
5204        __cntrl_->__add_weak();
5205}
5206
5207#ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES
5208
5209template<class _Tp>
5210inline
5211weak_ptr<_Tp>::weak_ptr(weak_ptr&& __r) _NOEXCEPT
5212    : __ptr_(__r.__ptr_),
5213      __cntrl_(__r.__cntrl_)
5214{
5215    __r.__ptr_ = 0;
5216    __r.__cntrl_ = 0;
5217}
5218
5219template<class _Tp>
5220template<class _Yp>
5221inline
5222weak_ptr<_Tp>::weak_ptr(weak_ptr<_Yp>&& __r,
5223                        typename enable_if<is_convertible<_Yp*, _Tp*>::value, __nat*>::type)
5224         _NOEXCEPT
5225    : __ptr_(__r.__ptr_),
5226      __cntrl_(__r.__cntrl_)
5227{
5228    __r.__ptr_ = 0;
5229    __r.__cntrl_ = 0;
5230}
5231
5232#endif  // _LIBCPP_HAS_NO_RVALUE_REFERENCES
5233
5234template<class _Tp>
5235weak_ptr<_Tp>::~weak_ptr()
5236{
5237    if (__cntrl_)
5238        __cntrl_->__release_weak();
5239}
5240
5241template<class _Tp>
5242inline
5243weak_ptr<_Tp>&
5244weak_ptr<_Tp>::operator=(weak_ptr const& __r) _NOEXCEPT
5245{
5246    weak_ptr(__r).swap(*this);
5247    return *this;
5248}
5249
5250template<class _Tp>
5251template<class _Yp>
5252inline
5253typename enable_if
5254<
5255    is_convertible<_Yp*, _Tp*>::value,
5256    weak_ptr<_Tp>&
5257>::type
5258weak_ptr<_Tp>::operator=(weak_ptr<_Yp> const& __r) _NOEXCEPT
5259{
5260    weak_ptr(__r).swap(*this);
5261    return *this;
5262}
5263
5264#ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES
5265
5266template<class _Tp>
5267inline
5268weak_ptr<_Tp>&
5269weak_ptr<_Tp>::operator=(weak_ptr&& __r) _NOEXCEPT
5270{
5271    weak_ptr(_VSTD::move(__r)).swap(*this);
5272    return *this;
5273}
5274
5275template<class _Tp>
5276template<class _Yp>
5277inline
5278typename enable_if
5279<
5280    is_convertible<_Yp*, _Tp*>::value,
5281    weak_ptr<_Tp>&
5282>::type
5283weak_ptr<_Tp>::operator=(weak_ptr<_Yp>&& __r) _NOEXCEPT
5284{
5285    weak_ptr(_VSTD::move(__r)).swap(*this);
5286    return *this;
5287}
5288
5289#endif  // _LIBCPP_HAS_NO_RVALUE_REFERENCES
5290
5291template<class _Tp>
5292template<class _Yp>
5293inline
5294typename enable_if
5295<
5296    is_convertible<_Yp*, _Tp*>::value,
5297    weak_ptr<_Tp>&
5298>::type
5299weak_ptr<_Tp>::operator=(shared_ptr<_Yp> const& __r) _NOEXCEPT
5300{
5301    weak_ptr(__r).swap(*this);
5302    return *this;
5303}
5304
5305template<class _Tp>
5306inline
5307void
5308weak_ptr<_Tp>::swap(weak_ptr& __r) _NOEXCEPT
5309{
5310    _VSTD::swap(__ptr_, __r.__ptr_);
5311    _VSTD::swap(__cntrl_, __r.__cntrl_);
5312}
5313
5314template<class _Tp>
5315inline _LIBCPP_INLINE_VISIBILITY
5316void
5317swap(weak_ptr<_Tp>& __x, weak_ptr<_Tp>& __y) _NOEXCEPT
5318{
5319    __x.swap(__y);
5320}
5321
5322template<class _Tp>
5323inline
5324void
5325weak_ptr<_Tp>::reset() _NOEXCEPT
5326{
5327    weak_ptr().swap(*this);
5328}
5329
5330template<class _Tp>
5331template<class _Yp>
5332shared_ptr<_Tp>::shared_ptr(const weak_ptr<_Yp>& __r,
5333                            typename enable_if<is_convertible<_Yp*, _Tp*>::value, __nat>::type)
5334    : __ptr_(__r.__ptr_),
5335      __cntrl_(__r.__cntrl_ ? __r.__cntrl_->lock() : __r.__cntrl_)
5336{
5337    if (__cntrl_ == 0)
5338#ifndef _LIBCPP_NO_EXCEPTIONS
5339        throw bad_weak_ptr();
5340#else
5341        assert(!"bad_weak_ptr");
5342#endif
5343}
5344
5345template<class _Tp>
5346shared_ptr<_Tp>
5347weak_ptr<_Tp>::lock() const _NOEXCEPT
5348{
5349    shared_ptr<_Tp> __r;
5350    __r.__cntrl_ = __cntrl_ ? __cntrl_->lock() : __cntrl_;
5351    if (__r.__cntrl_)
5352        __r.__ptr_ = __ptr_;
5353    return __r;
5354}
5355
5356#if _LIBCPP_STD_VER > 14
5357template <class _Tp = void> struct owner_less;
5358#else
5359template <class _Tp> struct owner_less;
5360#endif
5361
5362template <class _Tp>
5363struct _LIBCPP_TYPE_VIS_ONLY owner_less<shared_ptr<_Tp> >
5364    : binary_function<shared_ptr<_Tp>, shared_ptr<_Tp>, bool>
5365{
5366    typedef bool result_type;
5367    _LIBCPP_INLINE_VISIBILITY
5368    bool operator()(shared_ptr<_Tp> const& __x, shared_ptr<_Tp> const& __y) const
5369        {return __x.owner_before(__y);}
5370    _LIBCPP_INLINE_VISIBILITY
5371    bool operator()(shared_ptr<_Tp> const& __x,   weak_ptr<_Tp> const& __y) const
5372        {return __x.owner_before(__y);}
5373    _LIBCPP_INLINE_VISIBILITY
5374    bool operator()(  weak_ptr<_Tp> const& __x, shared_ptr<_Tp> const& __y) const
5375        {return __x.owner_before(__y);}
5376};
5377
5378template <class _Tp>
5379struct _LIBCPP_TYPE_VIS_ONLY owner_less<weak_ptr<_Tp> >
5380    : binary_function<weak_ptr<_Tp>, weak_ptr<_Tp>, bool>
5381{
5382    typedef bool result_type;
5383    _LIBCPP_INLINE_VISIBILITY
5384    bool operator()(  weak_ptr<_Tp> const& __x,   weak_ptr<_Tp> const& __y) const
5385        {return __x.owner_before(__y);}
5386    _LIBCPP_INLINE_VISIBILITY
5387    bool operator()(shared_ptr<_Tp> const& __x,   weak_ptr<_Tp> const& __y) const
5388        {return __x.owner_before(__y);}
5389    _LIBCPP_INLINE_VISIBILITY
5390    bool operator()(  weak_ptr<_Tp> const& __x, shared_ptr<_Tp> const& __y) const
5391        {return __x.owner_before(__y);}
5392};
5393
5394#if _LIBCPP_STD_VER > 14
5395template <>
5396struct _LIBCPP_TYPE_VIS_ONLY owner_less<void>
5397{
5398    template <class _Tp, class _Up>
5399    _LIBCPP_INLINE_VISIBILITY
5400    bool operator()( shared_ptr<_Tp> const& __x, shared_ptr<_Up> const& __y) const
5401        {return __x.owner_before(__y);}
5402    template <class _Tp, class _Up>
5403    _LIBCPP_INLINE_VISIBILITY
5404    bool operator()( shared_ptr<_Tp> const& __x,  weak_ptr<_Up> const& __y) const
5405        {return __x.owner_before(__y);}
5406    template <class _Tp, class _Up>
5407    _LIBCPP_INLINE_VISIBILITY
5408    bool operator()(   weak_ptr<_Tp> const& __x, shared_ptr<_Up> const& __y) const
5409        {return __x.owner_before(__y);}
5410    template <class _Tp, class _Up>
5411    _LIBCPP_INLINE_VISIBILITY
5412    bool operator()(   weak_ptr<_Tp> const& __x,   weak_ptr<_Up> const& __y) const
5413        {return __x.owner_before(__y);}
5414    typedef void is_transparent;
5415};
5416#endif
5417
5418template<class _Tp>
5419class _LIBCPP_TYPE_VIS_ONLY enable_shared_from_this
5420{
5421    mutable weak_ptr<_Tp> __weak_this_;
5422protected:
5423    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR
5424    enable_shared_from_this() _NOEXCEPT {}
5425    _LIBCPP_INLINE_VISIBILITY
5426    enable_shared_from_this(enable_shared_from_this const&) _NOEXCEPT {}
5427    _LIBCPP_INLINE_VISIBILITY
5428    enable_shared_from_this& operator=(enable_shared_from_this const&) _NOEXCEPT
5429        {return *this;}
5430    _LIBCPP_INLINE_VISIBILITY
5431    ~enable_shared_from_this() {}
5432public:
5433    _LIBCPP_INLINE_VISIBILITY
5434    shared_ptr<_Tp> shared_from_this()
5435        {return shared_ptr<_Tp>(__weak_this_);}
5436    _LIBCPP_INLINE_VISIBILITY
5437    shared_ptr<_Tp const> shared_from_this() const
5438        {return shared_ptr<const _Tp>(__weak_this_);}
5439
5440#if _LIBCPP_STD_VER > 14
5441    _LIBCPP_INLINE_VISIBILITY
5442    weak_ptr<_Tp> weak_from_this() _NOEXCEPT
5443       { return __weak_this_; }
5444
5445    _LIBCPP_INLINE_VISIBILITY
5446    weak_ptr<const _Tp> weak_from_this() const _NOEXCEPT
5447        { return __weak_this_; }
5448#endif // _LIBCPP_STD_VER > 14
5449
5450    template <class _Up> friend class shared_ptr;
5451};
5452
5453template <class _Tp>
5454struct _LIBCPP_TYPE_VIS_ONLY hash<shared_ptr<_Tp> >
5455{
5456    typedef shared_ptr<_Tp>      argument_type;
5457    typedef size_t               result_type;
5458    _LIBCPP_INLINE_VISIBILITY
5459    result_type operator()(const argument_type& __ptr) const _NOEXCEPT
5460    {
5461        return hash<_Tp*>()(__ptr.get());
5462    }
5463};
5464
5465template<class _CharT, class _Traits, class _Yp>
5466inline _LIBCPP_INLINE_VISIBILITY
5467basic_ostream<_CharT, _Traits>&
5468operator<<(basic_ostream<_CharT, _Traits>& __os, shared_ptr<_Yp> const& __p);
5469
5470
5471#if !defined(_LIBCPP_HAS_NO_ATOMIC_HEADER)
5472
5473class _LIBCPP_TYPE_VIS __sp_mut
5474{
5475    void* __lx;
5476public:
5477    void lock() _NOEXCEPT;
5478    void unlock() _NOEXCEPT;
5479
5480private:
5481    _LIBCPP_CONSTEXPR __sp_mut(void*) _NOEXCEPT;
5482    __sp_mut(const __sp_mut&);
5483    __sp_mut& operator=(const __sp_mut&);
5484
5485    friend _LIBCPP_FUNC_VIS __sp_mut& __get_sp_mut(const void*);
5486};
5487
5488_LIBCPP_FUNC_VIS __sp_mut& __get_sp_mut(const void*);
5489
5490template <class _Tp>
5491inline _LIBCPP_INLINE_VISIBILITY
5492bool
5493atomic_is_lock_free(const shared_ptr<_Tp>*)
5494{
5495    return false;
5496}
5497
5498template <class _Tp>
5499shared_ptr<_Tp>
5500atomic_load(const shared_ptr<_Tp>* __p)
5501{
5502    __sp_mut& __m = __get_sp_mut(__p);
5503    __m.lock();
5504    shared_ptr<_Tp> __q = *__p;
5505    __m.unlock();
5506    return __q;
5507}
5508
5509template <class _Tp>
5510inline _LIBCPP_INLINE_VISIBILITY
5511shared_ptr<_Tp>
5512atomic_load_explicit(const shared_ptr<_Tp>* __p, memory_order)
5513{
5514    return atomic_load(__p);
5515}
5516
5517template <class _Tp>
5518void
5519atomic_store(shared_ptr<_Tp>* __p, shared_ptr<_Tp> __r)
5520{
5521    __sp_mut& __m = __get_sp_mut(__p);
5522    __m.lock();
5523    __p->swap(__r);
5524    __m.unlock();
5525}
5526
5527template <class _Tp>
5528inline _LIBCPP_INLINE_VISIBILITY
5529void
5530atomic_store_explicit(shared_ptr<_Tp>* __p, shared_ptr<_Tp> __r, memory_order)
5531{
5532    atomic_store(__p, __r);
5533}
5534
5535template <class _Tp>
5536shared_ptr<_Tp>
5537atomic_exchange(shared_ptr<_Tp>* __p, shared_ptr<_Tp> __r)
5538{
5539    __sp_mut& __m = __get_sp_mut(__p);
5540    __m.lock();
5541    __p->swap(__r);
5542    __m.unlock();
5543    return __r;
5544}
5545
5546template <class _Tp>
5547inline _LIBCPP_INLINE_VISIBILITY
5548shared_ptr<_Tp>
5549atomic_exchange_explicit(shared_ptr<_Tp>* __p, shared_ptr<_Tp> __r, memory_order)
5550{
5551    return atomic_exchange(__p, __r);
5552}
5553
5554template <class _Tp>
5555bool
5556atomic_compare_exchange_strong(shared_ptr<_Tp>* __p, shared_ptr<_Tp>* __v, shared_ptr<_Tp> __w)
5557{
5558    shared_ptr<_Tp> __temp;
5559    __sp_mut& __m = __get_sp_mut(__p);
5560    __m.lock();
5561    if (__p->__owner_equivalent(*__v))
5562    {
5563        _VSTD::swap(__temp, *__p);
5564        *__p = __w;
5565        __m.unlock();
5566        return true;
5567    }
5568    _VSTD::swap(__temp, *__v);
5569    *__v = *__p;
5570    __m.unlock();
5571    return false;
5572}
5573
5574template <class _Tp>
5575inline _LIBCPP_INLINE_VISIBILITY
5576bool
5577atomic_compare_exchange_weak(shared_ptr<_Tp>* __p, shared_ptr<_Tp>* __v, shared_ptr<_Tp> __w)
5578{
5579    return atomic_compare_exchange_strong(__p, __v, __w);
5580}
5581
5582template <class _Tp>
5583inline _LIBCPP_INLINE_VISIBILITY
5584bool
5585atomic_compare_exchange_strong_explicit(shared_ptr<_Tp>* __p, shared_ptr<_Tp>* __v,
5586                                        shared_ptr<_Tp> __w, memory_order, memory_order)
5587{
5588    return atomic_compare_exchange_strong(__p, __v, __w);
5589}
5590
5591template <class _Tp>
5592inline _LIBCPP_INLINE_VISIBILITY
5593bool
5594atomic_compare_exchange_weak_explicit(shared_ptr<_Tp>* __p, shared_ptr<_Tp>* __v,
5595                                      shared_ptr<_Tp> __w, memory_order, memory_order)
5596{
5597    return atomic_compare_exchange_weak(__p, __v, __w);
5598}
5599
5600#endif  // !defined(_LIBCPP_HAS_NO_ATOMIC_HEADER)
5601
5602//enum class
5603struct _LIBCPP_TYPE_VIS pointer_safety
5604{
5605    enum __lx
5606    {
5607        relaxed,
5608        preferred,
5609        strict
5610    };
5611
5612    __lx __v_;
5613
5614    _LIBCPP_INLINE_VISIBILITY
5615    pointer_safety(__lx __v) : __v_(__v) {}
5616    _LIBCPP_INLINE_VISIBILITY
5617    operator int() const {return __v_;}
5618};
5619
5620_LIBCPP_FUNC_VIS void declare_reachable(void* __p);
5621_LIBCPP_FUNC_VIS void declare_no_pointers(char* __p, size_t __n);
5622_LIBCPP_FUNC_VIS void undeclare_no_pointers(char* __p, size_t __n);
5623_LIBCPP_FUNC_VIS pointer_safety get_pointer_safety() _NOEXCEPT;
5624_LIBCPP_FUNC_VIS void* __undeclare_reachable(void* __p);
5625
5626template <class _Tp>
5627inline _LIBCPP_INLINE_VISIBILITY
5628_Tp*
5629undeclare_reachable(_Tp* __p)
5630{
5631    return static_cast<_Tp*>(__undeclare_reachable(__p));
5632}
5633
5634_LIBCPP_FUNC_VIS void* align(size_t __align, size_t __sz, void*& __ptr, size_t& __space);
5635
5636// --- Helper for container swap --
5637template <typename _Alloc>
5638inline _LIBCPP_INLINE_VISIBILITY
5639void __swap_allocator(_Alloc & __a1, _Alloc & __a2)
5640#if _LIBCPP_STD_VER >= 14
5641    _NOEXCEPT
5642#else
5643    _NOEXCEPT_(__is_nothrow_swappable<_Alloc>::value)
5644#endif
5645{
5646    __swap_allocator(__a1, __a2,
5647      integral_constant<bool, _VSTD::allocator_traits<_Alloc>::propagate_on_container_swap::value>());
5648}
5649
5650template <typename _Alloc>
5651_LIBCPP_INLINE_VISIBILITY
5652void __swap_allocator(_Alloc & __a1, _Alloc & __a2, true_type)
5653#if _LIBCPP_STD_VER >= 14
5654    _NOEXCEPT
5655#else
5656    _NOEXCEPT_(__is_nothrow_swappable<_Alloc>::value)
5657#endif
5658{
5659    using _VSTD::swap;
5660    swap(__a1, __a2);
5661}
5662
5663template <typename _Alloc>
5664inline _LIBCPP_INLINE_VISIBILITY
5665void __swap_allocator(_Alloc &, _Alloc &, false_type) _NOEXCEPT {}
5666
5667template <typename _Alloc, typename _Traits=allocator_traits<_Alloc> >
5668struct __noexcept_move_assign_container : public integral_constant<bool,
5669    _Traits::propagate_on_container_move_assignment::value
5670#if _LIBCPP_STD_VER > 14
5671        || _Traits::is_always_equal::value
5672#else
5673        && is_nothrow_move_assignable<_Alloc>::value
5674#endif
5675    > {};
5676
5677
5678#ifndef _LIBCPP_HAS_NO_VARIADICS
5679template <class _Tp, class _Alloc>
5680struct __temp_value {
5681    typedef allocator_traits<_Alloc> _Traits;
5682
5683    typename aligned_storage<sizeof(_Tp), alignof(_Tp)>::type __v;
5684    _Alloc &__a;
5685
5686    _Tp *__addr() { return reinterpret_cast<_Tp *>(addressof(__v)); }
5687    _Tp &   get() { return *__addr(); }
5688
5689    template<class... _Args>
5690    __temp_value(_Alloc &__alloc, _Args&& ... __args) : __a(__alloc)
5691    { _Traits::construct(__a, __addr(), _VSTD::forward<_Args>(__args)...); }
5692
5693    ~__temp_value() { _Traits::destroy(__a, __addr()); }
5694    };
5695#endif
5696
5697_LIBCPP_END_NAMESPACE_STD
5698
5699#endif  // _LIBCPP_MEMORY
5700