Pull new libc++ into vendor branch.vendor/libc++/r185801

35 files changed, 2252 insertions, 1503 deletions

diff --git a/include/__bit_reference b/include/__bit_reference
index 1621deb88834..8ff3bf6d9ee7 100644
--- a/include/__bit_reference
+++ b/include/__bit_reference
@@ -333,7 +333,7 @@ __fill_n_false(__bit_iterator<_Cp, false> __first, typename _Cp::size_type __n)
     }
     // do middle whole words
     __storage_type __nw = __n / __bits_per_word;
-    _VSTD::memset(__first.__seg_, 0, __nw * sizeof(__storage_type));
+    _VSTD::memset(_VSTD::__to_raw_pointer(__first.__seg_), 0, __nw * sizeof(__storage_type));
     __n -= __nw * __bits_per_word;
     // do last partial word
     if (__n > 0)
@@ -363,7 +363,7 @@ __fill_n_true(__bit_iterator<_Cp, false> __first, typename _Cp::size_type __n)
     }
     // do middle whole words
     __storage_type __nw = __n / __bits_per_word;
-    _VSTD::memset(__first.__seg_, -1, __nw * sizeof(__storage_type));
+    _VSTD::memset(_VSTD::__to_raw_pointer(__first.__seg_), -1, __nw * sizeof(__storage_type));
     __n -= __nw * __bits_per_word;
     // do last partial word
     if (__n > 0)
@@ -430,7 +430,9 @@ __copy_aligned(__bit_iterator<_Cp, _IsConst> __first, __bit_iterator<_Cp, _IsCon
         // __first.__ctz_ == 0;
         // do middle words
         __storage_type __nw = __n / __bits_per_word;
-        _VSTD::memmove(__result.__seg_, __first.__seg_, __nw * sizeof(__storage_type));
+        _VSTD::memmove(_VSTD::__to_raw_pointer(__result.__seg_),
+                       _VSTD::__to_raw_pointer(__first.__seg_),
+                       __nw * sizeof(__storage_type));
         __n -= __nw * __bits_per_word;
         __result.__seg_ += __nw;
         // do last word
@@ -569,7 +571,9 @@ __copy_backward_aligned(__bit_iterator<_Cp, _IsConst> __first, __bit_iterator<_C
         __storage_type __nw = __n / __bits_per_word;
         __result.__seg_ -= __nw;
         __last.__seg_ -= __nw;
-        _VSTD::memmove(__result.__seg_, __last.__seg_, __nw * sizeof(__storage_type));
+        _VSTD::memmove(_VSTD::__to_raw_pointer(__result.__seg_),
+                       _VSTD::__to_raw_pointer(__last.__seg_),
+                       __nw * sizeof(__storage_type));
         __n -= __nw * __bits_per_word;
         // do last word
         if (__n > 0)
@@ -870,6 +874,7 @@ struct __bit_array
 {
     typedef typename _Cp::difference_type difference_type;
     typedef typename _Cp::__storage_type  __storage_type;
+    typedef typename _Cp::__storage_pointer __storage_pointer;
     typedef typename _Cp::iterator        iterator;
     static const unsigned __bits_per_word = _Cp::__bits_per_word;
     static const unsigned _Np = 4;
@@ -880,9 +885,15 @@ struct __bit_array
     _LIBCPP_INLINE_VISIBILITY static difference_type capacity()
         {return static_cast<difference_type>(_Np * __bits_per_word);}
     _LIBCPP_INLINE_VISIBILITY explicit __bit_array(difference_type __s) : __size_(__s) {}
-    _LIBCPP_INLINE_VISIBILITY iterator begin() {return iterator(__word_, 0);}
-    _LIBCPP_INLINE_VISIBILITY iterator end()   {return iterator(__word_ + __size_ / __bits_per_word,
-                                                  static_cast<unsigned>(__size_ % __bits_per_word));}
+    _LIBCPP_INLINE_VISIBILITY iterator begin()
+    {
+        return iterator(pointer_traits<__storage_pointer>::pointer_to(__word_[0]), 0);
+    }
+    _LIBCPP_INLINE_VISIBILITY iterator end()
+    {
+        return iterator(pointer_traits<__storage_pointer>::pointer_to(__word_[0]) + __size_ / __bits_per_word,
+                                                  static_cast<unsigned>(__size_ % __bits_per_word));
+    }
 };
 
 template <class _Cp>
diff --git a/include/__config b/include/__config
index 959390d56368..ca850d39bfbd 100644
--- a/include/__config
+++ b/include/__config
@@ -56,6 +56,18 @@
 # endif  // __LONG_LONG_SUPPORTED
 #endif  // __FreeBSD__
 
+#ifdef __NetBSD__
+# include <sys/endian.h>
+#  if _BYTE_ORDER == _LITTLE_ENDIAN
+#   define _LIBCPP_LITTLE_ENDIAN 1
+#   define _LIBCPP_BIG_ENDIAN    0
+# else  // _BYTE_ORDER == _LITTLE_ENDIAN
+#   define _LIBCPP_LITTLE_ENDIAN 0
+#   define _LIBCPP_BIG_ENDIAN    1
+# endif  // _BYTE_ORDER == _LITTLE_ENDIAN
+# define _LIBCPP_HAS_QUICK_EXIT
+#endif  // __NetBSD__
+
 #ifdef _WIN32
 #  define _LIBCPP_LITTLE_ENDIAN 1
 #  define _LIBCPP_BIG_ENDIAN    0
@@ -135,6 +147,10 @@
 
 #endif // _WIN32
 
+#ifndef __has_attribute
+#define __has_attribute(__x) 0
+#endif
+
 #ifndef _LIBCPP_HIDDEN
 #define _LIBCPP_HIDDEN __attribute__ ((__visibility__("hidden")))
 #endif
@@ -212,7 +228,9 @@ typedef __char32_t char32_t;
 #  define _LIBCPP_NORETURN __attribute__ ((noreturn))
 #endif
 
+#if !(__has_feature(cxx_defaulted_functions))
 #define _LIBCPP_HAS_NO_DEFAULTED_FUNCTIONS
+#endif  // !(__has_feature(cxx_defaulted_functions))
 
 #if !(__has_feature(cxx_deleted_functions))
 #define _LIBCPP_HAS_NO_DELETED_FUNCTIONS
@@ -272,9 +290,19 @@ typedef __char32_t char32_t;
 #define _LIBCPP_HAS_NO_CONSTEXPR
 #endif
 
-#if defined(__FreeBSD__) && (__ISO_C_VISIBLE >= 2011 || __cplusplus >= 201103L)
+#if __ISO_C_VISIBLE >= 2011 || __cplusplus >= 201103L
+#if defined(__FreeBSD__)
 #define _LIBCPP_HAS_QUICK_EXIT
 #define _LIBCPP_HAS_C11_FEATURES
+#elif defined(__linux__)
+#include <features.h>
+#if __GLIBC_PREREQ(2, 15)
+#define _LIBCPP_HAS_QUICK_EXIT
+#endif
+#if __GLIBC_PREREQ(2, 17)
+#define _LIBCPP_HAS_C11_FEATURES
+#endif
+#endif
 #endif
 
 #if (__has_feature(cxx_noexcept))
@@ -418,8 +446,14 @@ template <unsigned> struct __static_assert_check {};
 #define _LIBCPP_CONSTEXPR constexpr
 #endif
 
+#ifdef _LIBCPP_HAS_NO_DEFAULTED_FUNCTIONS
+#define _LIBCPP_DEFAULT {}
+#else
+#define _LIBCPP_DEFAULT = default;
+#endif
+
 #ifdef __GNUC__
-#define _NOALIAS __attribute__((malloc))
+#define _NOALIAS __attribute__((__malloc__))
 #else
 #define _NOALIAS
 #endif
@@ -451,7 +485,7 @@ template <unsigned> struct __static_assert_check {};
 #define _LIBCPP_EXTERN_TEMPLATE(...) extern template __VA_ARGS__;
 #endif
 
-#if defined(__APPLE__) || defined(__FreeBSD__) || defined(_WIN32) || defined(__sun__)
+#if defined(__APPLE__) || defined(__FreeBSD__) || defined(_WIN32) || defined(__sun__) || defined(__NetBSD__)
 #define _LIBCPP_LOCALE__L_EXTENSIONS 1
 #endif
 #ifdef __FreeBSD__
@@ -476,6 +510,14 @@ template <unsigned> struct __static_assert_check {};
 #   endif
 #endif
 
+#ifndef _LIBCPP_STD_VER
+#  if  __cplusplus <= 201103L
+#    define _LIBCPP_STD_VER 11
+#  else
+#    define _LIBCPP_STD_VER 13  // current year, or date of c++14 ratification
+#  endif
+#endif  // _LIBCPP_STD_VER
+
 #ifdef _LIBCPP_DEBUG2
 #   include <__debug>
 #else
diff --git a/include/__functional_base b/include/__functional_base
index 40a63a853d2b..5b0d7201d6f7 100644
--- a/include/__functional_base
+++ b/include/__functional_base
@@ -292,7 +292,8 @@ struct __weak_result_type<_Rp (_Cp::*)(_A1, _A2, _A3...) const volatile>
 
 // bullets 1 and 2
 
-template <class _Fp, class _A0, class ..._Args>
+template <class _Fp, class _A0, class ..._Args,
+            class>
 inline _LIBCPP_INLINE_VISIBILITY
 auto
 __invoke(_Fp&& __f, _A0&& __a0, _Args&& ...__args)
@@ -301,7 +302,8 @@ __invoke(_Fp&& __f, _A0&& __a0, _Args&& ...__args)
     return (_VSTD::forward<_A0>(__a0).*__f)(_VSTD::forward<_Args>(__args)...);
 }
 
-template <class _Fp, class _A0, class ..._Args>
+template <class _Fp, class _A0, class ..._Args,
+            class>
 inline _LIBCPP_INLINE_VISIBILITY
 auto
 __invoke(_Fp&& __f, _A0&& __a0, _Args&& ...__args)
@@ -312,7 +314,8 @@ __invoke(_Fp&& __f, _A0&& __a0, _Args&& ...__args)
 
 // bullets 3 and 4
 
-template <class _Fp, class _A0>
+template <class _Fp, class _A0,
+            class>
 inline _LIBCPP_INLINE_VISIBILITY
 auto
 __invoke(_Fp&& __f, _A0&& __a0)
@@ -321,7 +324,8 @@ __invoke(_Fp&& __f, _A0&& __a0)
     return _VSTD::forward<_A0>(__a0).*__f;
 }
 
-template <class _Fp, class _A0>
+template <class _Fp, class _A0,
+            class>
 inline _LIBCPP_INLINE_VISIBILITY
 auto
 __invoke(_Fp&& __f, _A0&& __a0)
diff --git a/include/__hash_table b/include/__hash_table
index 6f6050d33ebb..2b282d33a9e3 100644
--- a/include/__hash_table
+++ b/include/__hash_table
@@ -33,7 +33,6 @@ template <class _NodePtr>
 struct __hash_node_base
 {
     typedef __hash_node_base __first_node;
- //   typedef _NodePtr pointer;
 
     _NodePtr    __next_;
 
@@ -111,7 +110,7 @@ public:
     _LIBCPP_INLINE_VISIBILITY
         reference operator*() const {return __node_->__value_;}
     _LIBCPP_INLINE_VISIBILITY
-        pointer operator->() const {return _VSTD::addressof(__node_->__value_);}
+        pointer operator->() const {return pointer_traits<pointer>::pointer_to(__node_->__value_);}
 
     _LIBCPP_INLINE_VISIBILITY
     __hash_iterator& operator++()
@@ -189,7 +188,7 @@ public:
     _LIBCPP_INLINE_VISIBILITY
         reference operator*() const {return __node_->__value_;}
     _LIBCPP_INLINE_VISIBILITY
-        pointer operator->() const {return _VSTD::addressof(__node_->__value_);}
+        pointer operator->() const {return pointer_traits<pointer>::pointer_to(__node_->__value_);}
 
     _LIBCPP_INLINE_VISIBILITY
     __hash_const_iterator& operator++()
@@ -255,7 +254,7 @@ public:
     _LIBCPP_INLINE_VISIBILITY
         reference operator*() const {return __node_->__value_;}
     _LIBCPP_INLINE_VISIBILITY
-        pointer operator->() const {return &__node_->__value_;}
+        pointer operator->() const {return pointer_traits<pointer>::pointer_to(__node_->__value_);}
 
     _LIBCPP_INLINE_VISIBILITY
     __hash_local_iterator& operator++()
@@ -345,7 +344,7 @@ public:
     _LIBCPP_INLINE_VISIBILITY
         reference operator*() const {return __node_->__value_;}
     _LIBCPP_INLINE_VISIBILITY
-        pointer operator->() const {return &__node_->__value_;}
+        pointer operator->() const {return pointer_traits<pointer>::pointer_to(__node_->__value_);}
 
     _LIBCPP_INLINE_VISIBILITY
     __hash_const_local_iterator& operator++()
@@ -505,8 +504,15 @@ public:
                                                      __node_allocator;
     typedef allocator_traits<__node_allocator>       __node_traits;
     typedef typename __node_traits::pointer          __node_pointer;
-    typedef typename __node_traits::const_pointer    __node_const_pointer;
+    typedef typename __node_traits::pointer          __node_const_pointer;
     typedef __hash_node_base<__node_pointer>         __first_node;
+    typedef typename pointer_traits<__node_pointer>::template
+#ifndef _LIBCPP_HAS_NO_TEMPLATE_ALIASES
+            rebind<__first_node>
+#else
+            rebind<__first_node>::other
+#endif
+                                                     __node_base_pointer;
 
 private:
 
@@ -558,9 +564,9 @@ public:
 
 public:
     typedef __hash_iterator<__node_pointer>                   iterator;
-    typedef __hash_const_iterator<__node_const_pointer>       const_iterator;
+    typedef __hash_const_iterator<__node_pointer>             const_iterator;
     typedef __hash_local_iterator<__node_pointer>             local_iterator;
-    typedef __hash_const_local_iterator<__node_const_pointer> const_local_iterator;
+    typedef __hash_const_local_iterator<__node_pointer>       const_local_iterator;
 
     __hash_table()
         _NOEXCEPT_(
@@ -706,7 +712,7 @@ public:
 
     _LIBCPP_INLINE_VISIBILITY
     size_type max_bucket_count() const _NOEXCEPT
-        {return __bucket_list_.get_deleter().__alloc().max_size();}
+        {return __pointer_alloc_traits::max_size(__bucket_list_.get_deleter().__alloc());}
     size_type bucket_size(size_type __n) const;
     _LIBCPP_INLINE_VISIBILITY float load_factor() const _NOEXCEPT
     {
@@ -807,6 +813,9 @@ private:
 
     void __deallocate(__node_pointer __np) _NOEXCEPT;
     __node_pointer __detach() _NOEXCEPT;
+
+    template <class, class, class, class, class> friend class _LIBCPP_TYPE_VIS unordered_map;
+    template <class, class, class, class, class> friend class _LIBCPP_TYPE_VIS unordered_multimap;
 };
 
 template <class _Tp, class _Hash, class _Equal, class _Alloc>
@@ -893,7 +902,7 @@ __hash_table<_Tp, _Hash, _Equal, _Alloc>::__hash_table(__hash_table&& __u)
     if (size() > 0)
     {
         __bucket_list_[__constrain_hash(__p1_.first().__next_->__hash_, bucket_count())] =
-            static_cast<__node_pointer>(_VSTD::addressof(__p1_.first()));
+            static_cast<__node_pointer>(pointer_traits<__node_base_pointer>::pointer_to(__p1_.first()));
         __u.__p1_.first().__next_ = nullptr;
         __u.size() = 0;
     }
@@ -917,7 +926,7 @@ __hash_table<_Tp, _Hash, _Equal, _Alloc>::__hash_table(__hash_table&& __u,
             __p1_.first().__next_ = __u.__p1_.first().__next_;
             __u.__p1_.first().__next_ = nullptr;
             __bucket_list_[__constrain_hash(__p1_.first().__next_->__hash_, bucket_count())] =
-                static_cast<__node_pointer>(_VSTD::addressof(__p1_.first()));
+                static_cast<__node_pointer>(pointer_traits<__node_base_pointer>::pointer_to(__p1_.first()));
             size() = __u.size();
             __u.size() = 0;
         }
@@ -1014,7 +1023,7 @@ __hash_table<_Tp, _Hash, _Equal, _Alloc>::__move_assign(
     if (size() > 0)
     {
         __bucket_list_[__constrain_hash(__p1_.first().__next_->__hash_, bucket_count())] =
-            static_cast<__node_pointer>(_VSTD::addressof(__p1_.first()));
+            static_cast<__node_pointer>(pointer_traits<__node_base_pointer>::pointer_to(__p1_.first()));
         __u.__p1_.first().__next_ = nullptr;
         __u.size() = 0;
     }
@@ -1236,7 +1245,7 @@ __hash_table<_Tp, _Hash, _Equal, _Alloc>::__node_insert_unique(__node_pointer __
         __node_pointer __pn = __bucket_list_[__chash];
         if (__pn == nullptr)
         {
-            __pn = static_cast<__node_pointer>(_VSTD::addressof(__p1_.first()));
+            __pn = static_cast<__node_pointer>(pointer_traits<__node_base_pointer>::pointer_to(__p1_.first()));
             __nd->__next_ = __pn->__next_;
             __pn->__next_ = __nd;
             // fix up __bucket_list_
@@ -1274,7 +1283,7 @@ __hash_table<_Tp, _Hash, _Equal, _Alloc>::__node_insert_multi(__node_pointer __c
     __node_pointer __pn = __bucket_list_[__chash];
     if (__pn == nullptr)
     {
-        __pn = static_cast<__node_pointer>(_VSTD::addressof(__p1_.first()));
+        __pn = static_cast<__node_pointer>(pointer_traits<__node_base_pointer>::pointer_to(__p1_.first()));
         __cp->__next_ = __pn->__next_;
         __pn->__next_ = __cp;
         // fix up __bucket_list_
@@ -1322,7 +1331,7 @@ __hash_table<_Tp, _Hash, _Equal, _Alloc>::__node_insert_multi(
 {
     if (__p != end() && key_eq()(*__p, __cp->__value_))
     {
-        __node_pointer __np = const_cast<__node_pointer>(__p.__node_);
+        __node_pointer __np = __p.__node_;
         __cp->__hash_ = __np->__hash_;
         size_type __bc = bucket_count();
         if (size()+1 > __bc * max_load_factor() || __bc == 0)
@@ -1380,7 +1389,7 @@ __hash_table<_Tp, _Hash, _Equal, _Alloc>::__insert_unique(const value_type& __x)
         __node_pointer __pn = __bucket_list_[__chash];
         if (__pn == nullptr)
         {
-            __pn = static_cast<__node_pointer>(_VSTD::addressof(__p1_.first()));
+            __pn = static_cast<__node_pointer>(pointer_traits<__node_base_pointer>::pointer_to(__p1_.first()));
             __h->__next_ = __pn->__next_;
             __pn->__next_ = __h.get();
             // fix up __bucket_list_
@@ -1542,7 +1551,7 @@ __hash_table<_Tp, _Hash, _Equal, _Alloc>::__rehash(size_type __nbc)
     {
         for (size_type __i = 0; __i < __nbc; ++__i)
             __bucket_list_[__i] = nullptr;
-        __node_pointer __pp(static_cast<__node_pointer>(_VSTD::addressof(__p1_.first())));
+        __node_pointer __pp(static_cast<__node_pointer>(pointer_traits<__node_base_pointer>::pointer_to(__p1_.first())));
         __node_pointer __cp = __pp->__next_;
         if (__cp != nullptr)
         {
@@ -1700,7 +1709,7 @@ template <class _Tp, class _Hash, class _Equal, class _Alloc>
 typename __hash_table<_Tp, _Hash, _Equal, _Alloc>::iterator
 __hash_table<_Tp, _Hash, _Equal, _Alloc>::erase(const_iterator __p)
 {
-    __node_pointer __np = const_cast<__node_pointer>(__p.__node_);
+    __node_pointer __np = __p.__node_;
     iterator __r(__np);
     ++__r;
     remove(__p);
@@ -1717,7 +1726,7 @@ __hash_table<_Tp, _Hash, _Equal, _Alloc>::erase(const_iterator __first,
         ++__first;
         erase(__p);
     }
-    __node_pointer __np = const_cast<__node_pointer>(__last.__node_);
+    __node_pointer __np = __last.__node_;
     return iterator (__np);
 }
 
@@ -1757,7 +1766,7 @@ typename __hash_table<_Tp, _Hash, _Equal, _Alloc>::__node_holder
 __hash_table<_Tp, _Hash, _Equal, _Alloc>::remove(const_iterator __p) _NOEXCEPT
 {
     // current node
-    __node_pointer __cn = const_cast<__node_pointer>(__p.__node_);
+    __node_pointer __cn = __p.__node_;
     size_type __bc = bucket_count();
     size_t __chash = __constrain_hash(__cn->__hash_, __bc);
     // find previous node
@@ -1767,7 +1776,8 @@ __hash_table<_Tp, _Hash, _Equal, _Alloc>::remove(const_iterator __p) _NOEXCEPT
     // Fix up __bucket_list_
         // if __pn is not in same bucket (before begin is not in same bucket) &&
         //    if __cn->__next_ is not in same bucket (nullptr is not in same bucket)
-    if (__pn == _VSTD::addressof(__p1_.first()) || __constrain_hash(__pn->__hash_, __bc) != __chash)
+    if (__pn == static_cast<__node_pointer>(pointer_traits<__node_base_pointer>::pointer_to(__p1_.first()))
+                            || __constrain_hash(__pn->__hash_, __bc) != __chash)
     {
         if (__cn->__next_ == nullptr || __constrain_hash(__cn->__next_->__hash_, __bc) != __chash)
             __bucket_list_[__chash] = nullptr;
@@ -1907,10 +1917,10 @@ __hash_table<_Tp, _Hash, _Equal, _Alloc>::swap(__hash_table& __u)
     __p3_.swap(__u.__p3_);
     if (size() > 0)
         __bucket_list_[__constrain_hash(__p1_.first().__next_->__hash_, bucket_count())] =
-            static_cast<__node_pointer>(_VSTD::addressof(__p1_.first()));
+            static_cast<__node_pointer>(pointer_traits<__node_base_pointer>::pointer_to(__p1_.first()));
     if (__u.size() > 0)
         __u.__bucket_list_[__constrain_hash(__u.__p1_.first().__next_->__hash_, __u.bucket_count())] =
-            static_cast<__node_pointer>(_VSTD::addressof(__u.__p1_.first()));
+            static_cast<__node_pointer>(pointer_traits<__node_base_pointer>::pointer_to(__u.__p1_.first()));
 }
 
 template <class _Tp, class _Hash, class _Equal, class _Alloc>
diff --git a/include/__locale b/include/__locale
index 24d565b69adb..92f4e0ca7a7e 100644
--- a/include/__locale
+++ b/include/__locale
@@ -339,12 +339,12 @@ public:
     static const mask punct  = _PUNCT;
     static const mask xdigit = _HEX;
     static const mask blank  = _BLANK;
-#elif (defined(__APPLE__) || defined(__FreeBSD__)) || defined(EMSCRIPTEN)
+#elif defined(__APPLE__) || defined(__FreeBSD__) || defined(EMSCRIPTEN) || defined(__NetBSD__)
 #ifdef __APPLE__
     typedef __uint32_t mask;
 #elif defined(__FreeBSD__)
     typedef unsigned long mask;
-#elif defined(EMSCRIPTEN)
+#elif defined(EMSCRIPTEN) ||  defined(__NetBSD__)
     typedef unsigned short mask;
 #endif
     static const mask space  = _CTYPE_S;
@@ -356,7 +356,11 @@ public:
     static const mask digit  = _CTYPE_D;
     static const mask punct  = _CTYPE_P;
     static const mask xdigit = _CTYPE_X;
+# if defined(__NetBSD__)
+    static const mask blank  = _CTYPE_BL;
+# else
     static const mask blank  = _CTYPE_B;
+# endif
 #elif defined(__sun__)
     typedef unsigned int mask;
     static const mask space  = _ISSPACE;
@@ -596,6 +600,10 @@ public:
     static const int* __classic_upper_table() _NOEXCEPT;
     static const int* __classic_lower_table() _NOEXCEPT;
 #endif
+#if defined(__NetBSD__)
+    static const short* __classic_upper_table() _NOEXCEPT;
+    static const short* __classic_lower_table() _NOEXCEPT;
+#endif
 
 protected:
     ~ctype();
diff --git a/include/__split_buffer b/include/__split_buffer
index e0aa13b89883..f1c404f7741a 100644
--- a/include/__split_buffer
+++ b/include/__split_buffer
@@ -290,7 +290,7 @@ void
 __split_buffer<_Tp, _Allocator>::__destruct_at_begin(pointer __new_begin, false_type)
 {
     while (__begin_ != __new_begin)
-        __alloc_traits::destroy(__alloc(), __begin_++);
+        __alloc_traits::destroy(__alloc(), __to_raw_pointer(__begin_++));
 }
 
 template <class _Tp, class _Allocator>
@@ -307,7 +307,7 @@ void
 __split_buffer<_Tp, _Allocator>::__destruct_at_end(pointer __new_last, false_type) _NOEXCEPT
 {
     while (__new_last != __end_)
-        __alloc_traits::destroy(__alloc(), --__end_);
+        __alloc_traits::destroy(__alloc(), __to_raw_pointer(--__end_));
 }
 
 template <class _Tp, class _Allocator>
@@ -320,7 +320,7 @@ __split_buffer<_Tp, _Allocator>::__destruct_at_end(pointer __new_last, true_type
 
 template <class _Tp, class _Allocator>
 __split_buffer<_Tp, _Allocator>::__split_buffer(size_type __cap, size_type __start, __alloc_rr& __a)
-    : __end_cap_(0, __a)
+    : __end_cap_(nullptr, __a)
 {
     __first_ = __cap != 0 ? __alloc_traits::allocate(__alloc(), __cap) : nullptr;
     __begin_ = __end_ = __first_ + __start;
@@ -331,21 +331,21 @@ template <class _Tp, class _Allocator>
 _LIBCPP_INLINE_VISIBILITY inline
 __split_buffer<_Tp, _Allocator>::__split_buffer()
     _NOEXCEPT_(is_nothrow_default_constructible<allocator_type>::value)
-    : __first_(0), __begin_(0), __end_(0), __end_cap_(0)
+    : __first_(nullptr), __begin_(nullptr), __end_(nullptr), __end_cap_(nullptr)
 {
 }
 
 template <class _Tp, class _Allocator>
 _LIBCPP_INLINE_VISIBILITY inline
 __split_buffer<_Tp, _Allocator>::__split_buffer(__alloc_rr& __a)
-    : __first_(0), __begin_(0), __end_(0), __end_cap_(0, __a)
+    : __first_(nullptr), __begin_(nullptr), __end_(nullptr), __end_cap_(nullptr, __a)
 {
 }
 
 template <class _Tp, class _Allocator>
 _LIBCPP_INLINE_VISIBILITY inline
 __split_buffer<_Tp, _Allocator>::__split_buffer(const __alloc_rr& __a)
-    : __first_(0), __begin_(0), __end_(0), __end_cap_(0, __a)
+    : __first_(nullptr), __begin_(nullptr), __end_(nullptr), __end_cap_(nullptr, __a)
 {
 }
 
diff --git a/include/__std_stream b/include/__std_stream
index 8ca413eb6a1e..cff43317e580 100644
--- a/include/__std_stream
+++ b/include/__std_stream
@@ -55,6 +55,8 @@ private:
     const codecvt<char_type, char, state_type>* __cv_;
     state_type* __st_;
     int __encoding_;
+    int_type __last_consumed_;
+    bool __last_consumed_is_next_;
     bool __always_noconv_;
 
     __stdinbuf(const __stdinbuf&);
@@ -66,7 +68,9 @@ private:
 template <class _CharT>
 __stdinbuf<_CharT>::__stdinbuf(FILE* __fp, state_type* __st)
     : __file_(__fp),
-      __st_(__st)
+      __st_(__st),
+      __last_consumed_(traits_type::eof()),
+      __last_consumed_is_next_(false)
 {
     imbue(this->getloc());
 }
@@ -100,6 +104,16 @@ template <class _CharT>
 typename __stdinbuf<_CharT>::int_type
 __stdinbuf<_CharT>::__getchar(bool __consume)
 {
+    if (__last_consumed_is_next_)
+    {
+        int_type __result = __last_consumed_;
+        if (__consume)
+        {
+            __last_consumed_ = traits_type::eof();
+            __last_consumed_is_next_ = false;
+        }
+        return __result;
+    }
     char __extbuf[__limit];
     int __nread = _VSTD::max(1, __encoding_);
     for (int __i = 0; __i < __nread; ++__i)
@@ -154,6 +168,8 @@ __stdinbuf<_CharT>::__getchar(bool __consume)
                 return traits_type::eof();
         }
     }
+    else
+        __last_consumed_ = traits_type::to_int_type(__1buf);
     return traits_type::to_int_type(__1buf);
 }
 
@@ -162,28 +178,41 @@ typename __stdinbuf<_CharT>::int_type
 __stdinbuf<_CharT>::pbackfail(int_type __c)
 {
     if (traits_type::eq_int_type(__c, traits_type::eof()))
-        return __c;
-    char __extbuf[__limit];
-    char* __enxt;
-    const char_type __ci = traits_type::to_char_type(__c);
-    const char_type* __inxt;
-    switch (__cv_->out(*__st_, &__ci, &__ci + 1, __inxt,
-                              __extbuf, __extbuf + sizeof(__extbuf), __enxt))
     {
-    case _VSTD::codecvt_base::ok:
-        break;
-    case _VSTD::codecvt_base::noconv:
-        __extbuf[0] = static_cast<char>(__c);
-        __enxt = __extbuf + 1;
-        break;
-    case codecvt_base::partial:
-    case codecvt_base::error:
-        return traits_type::eof();
+        if (!__last_consumed_is_next_)
+        {
+            __c = __last_consumed_;
+            __last_consumed_is_next_ = !traits_type::eq_int_type(__last_consumed_,
+                                                                 traits_type::eof());
+        }
+        return __c;
     }
-    while (__enxt > __extbuf)
-        if (ungetc(*--__enxt, __file_) == EOF)
+    if (__last_consumed_is_next_)
+    {
+        char __extbuf[__limit];
+        char* __enxt;
+        const char_type __ci = traits_type::to_char_type(__last_consumed_);
+        const char_type* __inxt;
+        switch (__cv_->out(*__st_, &__ci, &__ci + 1, __inxt,
+                                  __extbuf, __extbuf + sizeof(__extbuf), __enxt))
+        {
+        case _VSTD::codecvt_base::ok:
+            break;
+        case _VSTD::codecvt_base::noconv:
+            __extbuf[0] = static_cast<char>(__last_consumed_);
+            __enxt = __extbuf + 1;
+            break;
+        case codecvt_base::partial:
+        case codecvt_base::error:
             return traits_type::eof();
- return traits_type::not_eof(__c);
+        }
+        while (__enxt > __extbuf)
+            if (ungetc(*--__enxt, __file_) == EOF)
+                return traits_type::eof();
+    }
+    __last_consumed_ = __c;
+    __last_consumed_is_next_ = true;
+    return __c;
 }
 
 // __stdoutbuf
@@ -234,30 +263,31 @@ __stdoutbuf<_CharT>::overflow(int_type __c)
     char_type __1buf;
     if (!traits_type::eq_int_type(__c, traits_type::eof()))
     {
-        this->setp(&__1buf, &__1buf+1);
-        *this->pptr() = traits_type::to_char_type(__c);
-        this->pbump(1);
+        __1buf = traits_type::to_char_type(__c);
         if (__always_noconv_)
         {
-            if (fwrite(this->pbase(), sizeof(char_type), 1, __file_) != 1)
+            if (fwrite(&__1buf, sizeof(char_type), 1, __file_) != 1)
                 return traits_type::eof();
         }
         else
         {
             char* __extbe = __extbuf;
             codecvt_base::result __r;
+            char_type* pbase = &__1buf;
+            char_type* pptr = pbase + 1;
+            char_type* epptr = pptr;
             do
             {
                 const char_type* __e;
-                __r = __cv_->out(*__st_, this->pbase(), this->pptr(), __e,
+                __r = __cv_->out(*__st_, pbase, pptr, __e,
                                         __extbuf,
                                         __extbuf + sizeof(__extbuf),
                                         __extbe);
-                if (__e == this->pbase())
+                if (__e == pbase)
                     return traits_type::eof();
                 if (__r == codecvt_base::noconv)
                 {
-                    if (fwrite(this->pbase(), 1, 1, __file_) != 1)
+                    if (fwrite(pbase, 1, 1, __file_) != 1)
                         return traits_type::eof();
                 }
                 else if (__r == codecvt_base::ok || __r == codecvt_base::partial)
@@ -267,15 +297,13 @@ __stdoutbuf<_CharT>::overflow(int_type __c)
                         return traits_type::eof();
                     if (__r == codecvt_base::partial)
                     {
-                        this->setp((char_type*)__e, this->pptr());
-                        this->pbump(static_cast<int>(this->epptr() - this->pbase()));
+                        pbase = (char_type*)__e;
                     }
                 }
                 else
                     return traits_type::eof();
             } while (__r == codecvt_base::partial);
         }
-        this->setp(0, 0);
     }
     return traits_type::not_eof(__c);
 }
diff --git a/include/__tree b/include/__tree
index cd6d7efaae84..9ffc38d2287e 100644
--- a/include/__tree
+++ b/include/__tree
@@ -644,7 +644,8 @@ public:
     _LIBCPP_INLINE_VISIBILITY __tree_iterator() _NOEXCEPT {}
 
     _LIBCPP_INLINE_VISIBILITY reference operator*() const {return __ptr_->__value_;}
-    _LIBCPP_INLINE_VISIBILITY pointer operator->() const {return &__ptr_->__value_;}
+    _LIBCPP_INLINE_VISIBILITY pointer operator->() const
+        {return pointer_traits<pointer>::pointer_to(__ptr_->__value_);}
 
     _LIBCPP_INLINE_VISIBILITY
     __tree_iterator& operator++()
@@ -686,7 +687,7 @@ class _LIBCPP_TYPE_VIS __tree_const_iterator
 {
     typedef _ConstNodePtr                                         __node_pointer;
     typedef typename pointer_traits<__node_pointer>::element_type __node;
-    typedef const typename __node::base                           __node_base;
+    typedef typename __node::base                                 __node_base;
     typedef typename pointer_traits<__node_pointer>::template
 #ifndef _LIBCPP_HAS_NO_TEMPLATE_ALIASES
             rebind<__node_base>
@@ -729,7 +730,8 @@ public:
         : __ptr_(__p.__ptr_) {}
 
     _LIBCPP_INLINE_VISIBILITY reference operator*() const {return __ptr_->__value_;}
-    _LIBCPP_INLINE_VISIBILITY pointer operator->() const {return &__ptr_->__value_;}
+    _LIBCPP_INLINE_VISIBILITY pointer operator->() const
+        {return pointer_traits<pointer>::pointer_to(__ptr_->__value_);}
 
     _LIBCPP_INLINE_VISIBILITY
     __tree_const_iterator& operator++()
@@ -779,8 +781,10 @@ public:
     typedef typename __alloc_traits::size_type       size_type;
     typedef typename __alloc_traits::difference_type difference_type;
 
-    typedef __tree_node<value_type, typename __alloc_traits::void_pointer> __node;
-    typedef __tree_node_base<typename __alloc_traits::void_pointer> __node_base;
+    typedef typename __alloc_traits::void_pointer  __void_pointer;
+
+    typedef __tree_node<value_type, __void_pointer> __node;
+    typedef __tree_node_base<__void_pointer>        __node_base;
     typedef typename __alloc_traits::template
 #ifndef _LIBCPP_HAS_NO_TEMPLATE_ALIASES
             rebind_alloc<__node>
@@ -790,9 +794,9 @@ public:
                                                      __node_allocator;
     typedef allocator_traits<__node_allocator>       __node_traits;
     typedef typename __node_traits::pointer          __node_pointer;
-    typedef typename __node_traits::const_pointer    __node_const_pointer;
+    typedef typename __node_traits::pointer          __node_const_pointer;
     typedef typename __node_base::pointer            __node_base_pointer;
-    typedef typename __node_base::const_pointer      __node_base_const_pointer;
+    typedef typename __node_base::pointer            __node_base_const_pointer;
 private:
     typedef typename __node_base::base __end_node_t;
     typedef typename pointer_traits<__node_pointer>::template
@@ -804,9 +808,9 @@ private:
                                                      __end_node_ptr;
     typedef typename pointer_traits<__node_pointer>::template
 #ifndef _LIBCPP_HAS_NO_TEMPLATE_ALIASES
-            rebind<const __end_node_t>
+            rebind<__end_node_t>
 #else
-            rebind<const __end_node_t>::other
+            rebind<__end_node_t>::other
 #endif
                                                      __end_node_const_ptr;
 
@@ -828,7 +832,7 @@ public:
     {
         return static_cast<__node_const_pointer>
                (
-                   pointer_traits<__end_node_const_ptr>::pointer_to(__pair1_.first())
+                   pointer_traits<__end_node_const_ptr>::pointer_to(const_cast<__end_node_t&>(__pair1_.first()))
                );
     }
     _LIBCPP_INLINE_VISIBILITY
@@ -865,7 +869,7 @@ public:
         {return static_cast<__node_const_pointer>(__end_node()->__left_);}
 
     typedef __tree_iterator<value_type, __node_pointer, difference_type>             iterator;
-    typedef __tree_const_iterator<value_type, __node_const_pointer, difference_type> const_iterator;
+    typedef __tree_const_iterator<value_type, __node_pointer, difference_type> const_iterator;
 
     explicit __tree(const value_compare& __comp)
         _NOEXCEPT_(
@@ -1102,6 +1106,9 @@ private:
 
     __node_pointer __detach();
     static __node_pointer __detach(__node_pointer);
+
+    template <class, class, class, class> friend class _LIBCPP_TYPE_VIS map;
+    template <class, class, class, class> friend class _LIBCPP_TYPE_VIS multimap;
 };
 
 template <class _Tp, class _Compare, class _Allocator>
@@ -1161,7 +1168,7 @@ __tree<_Tp, _Compare, _Allocator>::__detach(__node_pointer __cache)
 {
     if (__cache->__parent_ == nullptr)
         return nullptr;
-    if (__tree_is_left_child(__cache))
+    if (__tree_is_left_child(static_cast<__node_base_pointer>(__cache)))
     {
         __cache->__parent_->__left_ = nullptr;
         __cache = static_cast<__node_pointer>(__cache->__parent_);
@@ -1294,7 +1301,7 @@ __tree<_Tp, _Compare, _Allocator>::__tree(__tree&& __t)
         __begin_node() = __end_node();
     else
     {
-        __end_node()->__left_->__parent_ = __end_node();
+        __end_node()->__left_->__parent_ = static_cast<__node_base_pointer>(__end_node());
         __t.__begin_node() = __t.__end_node();
         __t.__end_node()->__left_ = nullptr;
         __t.size() = 0;
@@ -1314,7 +1321,7 @@ __tree<_Tp, _Compare, _Allocator>::__tree(__tree&& __t, const allocator_type& __
         {
             __begin_node() = __t.__begin_node();
             __end_node()->__left_ = __t.__end_node()->__left_;
-            __end_node()->__left_->__parent_ = __end_node();
+            __end_node()->__left_->__parent_ = static_cast<__node_base_pointer>(__end_node());
             size() = __t.size();
             __t.__begin_node() = __t.__end_node();
             __t.__end_node()->__left_ = nullptr;
@@ -1342,7 +1349,7 @@ __tree<_Tp, _Compare, _Allocator>::__move_assign(__tree& __t, true_type)
         __begin_node() = __end_node();
     else
     {
-        __end_node()->__left_->__parent_ = __end_node();
+        __end_node()->__left_->__parent_ = static_cast<__node_base_pointer>(__end_node());
         __t.__begin_node() = __t.__end_node();
         __t.__end_node()->__left_ = nullptr;
         __t.size() = 0;
@@ -1447,11 +1454,11 @@ __tree<_Tp, _Compare, _Allocator>::swap(__tree& __t)
     if (size() == 0)
         __begin_node() = __end_node();
     else
-        __end_node()->__left_->__parent_ = __end_node();
+        __end_node()->__left_->__parent_ = static_cast<__node_base_pointer>(__end_node());
     if (__t.size() == 0)
         __t.__begin_node() = __t.__end_node();
     else
-        __t.__end_node()->__left_->__parent_ = __t.__end_node();
+        __t.__end_node()->__left_->__parent_ = static_cast<__node_base_pointer>(__t.__end_node());
 }
 
 template <class _Tp, class _Compare, class _Allocator>
@@ -1483,7 +1490,7 @@ __tree<_Tp, _Compare, _Allocator>::__find_leaf_low(typename __node_base::pointer
                     __nd = static_cast<__node_pointer>(__nd->__right_);
                 else
                 {
-                    __parent = __nd;
+                    __parent = static_cast<__node_base_pointer>(__nd);
                     return __parent->__right_;
                 }
             }
@@ -1493,13 +1500,13 @@ __tree<_Tp, _Compare, _Allocator>::__find_leaf_low(typename __node_base::pointer
                     __nd = static_cast<__node_pointer>(__nd->__left_);
                 else
                 {
-                    __parent = __nd;
+                    __parent = static_cast<__node_base_pointer>(__nd);
                     return __parent->__left_;
                 }
             }
         }
     }
-    __parent = __end_node();
+    __parent = static_cast<__node_base_pointer>(__end_node());
     return __parent->__left_;
 }
 
@@ -1522,7 +1529,7 @@ __tree<_Tp, _Compare, _Allocator>::__find_leaf_high(typename __node_base::pointe
                     __nd = static_cast<__node_pointer>(__nd->__left_);
                 else
                 {
-                    __parent = __nd;
+                    __parent = static_cast<__node_base_pointer>(__nd);
                     return __parent->__left_;
                 }
             }
@@ -1532,13 +1539,13 @@ __tree<_Tp, _Compare, _Allocator>::__find_leaf_high(typename __node_base::pointe
                     __nd = static_cast<__node_pointer>(__nd->__right_);
                 else
                 {
-                    __parent = __nd;
+                    __parent = static_cast<__node_base_pointer>(__nd);
                     return __parent->__right_;
                 }
             }
         }
     }
-    __parent = __end_node();
+    __parent = static_cast<__node_base_pointer>(__end_node());
     return __parent->__left_;
 }
 
@@ -1563,12 +1570,12 @@ __tree<_Tp, _Compare, _Allocator>::__find_leaf(const_iterator __hint,
             // *prev(__hint) <= __v <= *__hint
             if (__hint.__ptr_->__left_ == nullptr)
             {
-                __parent = const_cast<__node_pointer&>(__hint.__ptr_);
+                __parent = static_cast<__node_base_pointer>(__hint.__ptr_);
                 return __parent->__left_;
             }
             else
             {
-                __parent = const_cast<__node_pointer&>(__prior.__ptr_);
+                __parent = static_cast<__node_base_pointer>(__prior.__ptr_);
                 return __parent->__right_;
             }
         }
@@ -1600,7 +1607,7 @@ __tree<_Tp, _Compare, _Allocator>::__find_equal(typename __node_base::pointer& _
                     __nd = static_cast<__node_pointer>(__nd->__left_);
                 else
                 {
-                    __parent = __nd;
+                    __parent = static_cast<__node_base_pointer>(__nd);
                     return __parent->__left_;
                 }
             }
@@ -1610,18 +1617,18 @@ __tree<_Tp, _Compare, _Allocator>::__find_equal(typename __node_base::pointer& _
                     __nd = static_cast<__node_pointer>(__nd->__right_);
                 else
                 {
-                    __parent = __nd;
+                    __parent = static_cast<__node_base_pointer>(__nd);
                     return __parent->__right_;
                 }
             }
             else
             {
-                __parent = __nd;
+                __parent = static_cast<__node_base_pointer>(__nd);
                 return __parent;
             }
         }
     }
-    __parent = __end_node();
+    __parent = static_cast<__node_base_pointer>(__end_node());
     return __parent->__left_;
 }
 
@@ -1648,12 +1655,12 @@ __tree<_Tp, _Compare, _Allocator>::__find_equal(const_iterator __hint,
             // *prev(__hint) < __v < *__hint
             if (__hint.__ptr_->__left_ == nullptr)
             {
-                __parent = const_cast<__node_pointer&>(__hint.__ptr_);
+                __parent = static_cast<__node_base_pointer>(__hint.__ptr_);
                 return __parent->__left_;
             }
             else
             {
-                __parent = const_cast<__node_pointer&>(__prior.__ptr_);
+                __parent = static_cast<__node_base_pointer>(__prior.__ptr_);
                 return __parent->__right_;
             }
         }
@@ -1669,12 +1676,12 @@ __tree<_Tp, _Compare, _Allocator>::__find_equal(const_iterator __hint,
             // *__hint < __v < *_VSTD::next(__hint)
             if (__hint.__ptr_->__right_ == nullptr)
             {
-                __parent = const_cast<__node_pointer&>(__hint.__ptr_);
+                __parent = static_cast<__node_base_pointer>(__hint.__ptr_);
                 return __parent->__right_;
             }
             else
             {
-                __parent = const_cast<__node_pointer&>(__next.__ptr_);
+                __parent = static_cast<__node_base_pointer>(__next.__ptr_);
                 return __parent->__left_;
             }
         }
@@ -1682,7 +1689,7 @@ __tree<_Tp, _Compare, _Allocator>::__find_equal(const_iterator __hint,
         return __find_equal(__parent, __v);
     }
     // else __v == *__hint
-    __parent = const_cast<__node_pointer&>(__hint.__ptr_);
+    __parent = static_cast<__node_base_pointer>(__hint.__ptr_);
     return __parent;
 }
 
@@ -1729,7 +1736,7 @@ __tree<_Tp, _Compare, _Allocator>::__emplace_unique(_Args&&... __args)
     bool __inserted = false;
     if (__child == nullptr)
     {
-        __insert_node_at(__parent, __child, __h.get());
+        __insert_node_at(__parent, __child, static_cast<__node_base_pointer>(__h.get()));
         __r = __h.release();
         __inserted = true;
     }
@@ -1747,7 +1754,7 @@ __tree<_Tp, _Compare, _Allocator>::__emplace_hint_unique(const_iterator __p, _Ar
     __node_pointer __r = static_cast<__node_pointer>(__child);
     if (__child == nullptr)
     {
-        __insert_node_at(__parent, __child, __h.get());
+        __insert_node_at(__parent, __child, static_cast<__node_base_pointer>(__h.get()));
         __r = __h.release();
     }
     return iterator(__r);
@@ -1761,7 +1768,7 @@ __tree<_Tp, _Compare, _Allocator>::__emplace_multi(_Args&&... __args)
     __node_holder __h = __construct_node(_VSTD::forward<_Args>(__args)...);
     __node_base_pointer __parent;
     __node_base_pointer& __child = __find_leaf_high(__parent, __h->__value_);
-    __insert_node_at(__parent, __child, __h.get());
+    __insert_node_at(__parent, __child, static_cast<__node_base_pointer>(__h.get()));
     return iterator(static_cast<__node_pointer>(__h.release()));
 }
 
@@ -1774,7 +1781,7 @@ __tree<_Tp, _Compare, _Allocator>::__emplace_hint_multi(const_iterator __p,
     __node_holder __h = __construct_node(_VSTD::forward<_Args>(__args)...);
     __node_base_pointer __parent;
     __node_base_pointer& __child = __find_leaf(__p, __parent, __h->__value_);
-    __insert_node_at(__parent, __child, __h.get());
+    __insert_node_at(__parent, __child, static_cast<__node_base_pointer>(__h.get()));
     return iterator(static_cast<__node_pointer>(__h.release()));
 }
 
@@ -1812,7 +1819,7 @@ __tree<_Tp, _Compare, _Allocator>::__insert_multi(_Vp&& __v)
     __node_holder __h = __construct_node(_VSTD::forward<_Vp>(__v));
     __node_base_pointer __parent;
     __node_base_pointer& __child = __find_leaf_high(__parent, __h->__value_);
-    __insert_node_at(__parent, __child, __h.get());
+    __insert_node_at(__parent, __child, static_cast<__node_base_pointer>(__h.get()));
     return iterator(__h.release());
 }
 
@@ -1824,7 +1831,7 @@ __tree<_Tp, _Compare, _Allocator>::__insert_multi(const_iterator __p, _Vp&& __v)
     __node_holder __h = __construct_node(_VSTD::forward<_Vp>(__v));
     __node_base_pointer __parent;
     __node_base_pointer& __child = __find_leaf(__p, __parent, __h->__value_);
-    __insert_node_at(__parent, __child, __h.get());
+    __insert_node_at(__parent, __child, static_cast<__node_base_pointer>(__h.get()));
     return iterator(__h.release());
 }
 
@@ -1854,7 +1861,7 @@ __tree<_Tp, _Compare, _Allocator>::__insert_unique(const value_type& __v)
     if (__child == nullptr)
     {
         __node_holder __h = __construct_node(__v);
-        __insert_node_at(__parent, __child, __h.get());
+        __insert_node_at(__parent, __child, static_cast<__node_base_pointer>(__h.get()));
         __r = __h.release();
         __inserted = true;
     }
@@ -1871,7 +1878,7 @@ __tree<_Tp, _Compare, _Allocator>::__insert_unique(const_iterator __p, const val
     if (__child == nullptr)
     {
         __node_holder __h = __construct_node(__v);
-        __insert_node_at(__parent, __child, __h.get());
+        __insert_node_at(__parent, __child, static_cast<__node_base_pointer>(__h.get()));
         __r = __h.release();
     }
     return iterator(__r);
@@ -1884,7 +1891,7 @@ __tree<_Tp, _Compare, _Allocator>::__insert_multi(const value_type& __v)
     __node_base_pointer __parent;
     __node_base_pointer& __child = __find_leaf_high(__parent, __v);
     __node_holder __h = __construct_node(__v);
-    __insert_node_at(__parent, __child, __h.get());
+    __insert_node_at(__parent, __child, static_cast<__node_base_pointer>(__h.get()));
     return iterator(__h.release());
 }
 
@@ -1895,7 +1902,7 @@ __tree<_Tp, _Compare, _Allocator>::__insert_multi(const_iterator __p, const valu
     __node_base_pointer __parent;
     __node_base_pointer& __child = __find_leaf(__p, __parent, __v);
     __node_holder __h = __construct_node(__v);
-    __insert_node_at(__parent, __child, __h.get());
+    __insert_node_at(__parent, __child, static_cast<__node_base_pointer>(__h.get()));
     return iterator(__h.release());
 }
 
@@ -1909,7 +1916,7 @@ __tree<_Tp, _Compare, _Allocator>::__node_insert_unique(__node_pointer __nd)
     bool __inserted = false;
     if (__child == nullptr)
     {
-        __insert_node_at(__parent, __child, __nd);
+        __insert_node_at(__parent, __child, static_cast<__node_base_pointer>(__nd));
         __r = __nd;
         __inserted = true;
     }
@@ -1926,7 +1933,7 @@ __tree<_Tp, _Compare, _Allocator>::__node_insert_unique(const_iterator __p,
     __node_pointer __r = static_cast<__node_pointer>(__child);
     if (__child == nullptr)
     {
-        __insert_node_at(__parent, __child, __nd);
+        __insert_node_at(__parent, __child, static_cast<__node_base_pointer>(__nd));
         __r = __nd;
     }
     return iterator(__r);
@@ -1938,7 +1945,7 @@ __tree<_Tp, _Compare, _Allocator>::__node_insert_multi(__node_pointer __nd)
 {
     __node_base_pointer __parent;
     __node_base_pointer& __child = __find_leaf_high(__parent, __nd->__value_);
-    __insert_node_at(__parent, __child, __nd);
+    __insert_node_at(__parent, __child, static_cast<__node_base_pointer>(__nd));
     return iterator(__nd);
 }
 
@@ -1949,7 +1956,7 @@ __tree<_Tp, _Compare, _Allocator>::__node_insert_multi(const_iterator __p,
 {
     __node_base_pointer __parent;
     __node_base_pointer& __child = __find_leaf(__p, __parent, __nd->__value_);
-    __insert_node_at(__parent, __child, __nd);
+    __insert_node_at(__parent, __child, static_cast<__node_base_pointer>(__nd));
     return iterator(__nd);
 }
 
@@ -1957,7 +1964,7 @@ template <class _Tp, class _Compare, class _Allocator>
 typename __tree<_Tp, _Compare, _Allocator>::iterator
 __tree<_Tp, _Compare, _Allocator>::erase(const_iterator __p)
 {
-    __node_pointer __np = const_cast<__node_pointer>(__p.__ptr_);
+    __node_pointer __np = __p.__ptr_;
     iterator __r(__np);
     ++__r;
     if (__begin_node() == __np)
@@ -1977,7 +1984,7 @@ __tree<_Tp, _Compare, _Allocator>::erase(const_iterator __f, const_iterator __l)
 {
     while (__f != __l)
         __f = erase(__f);
-    return iterator(const_cast<__node_pointer>(__l.__ptr_));
+    return iterator(__l.__ptr_);
 }
 
 template <class _Tp, class _Compare, class _Allocator>
@@ -2264,7 +2271,7 @@ template <class _Tp, class _Compare, class _Allocator>
 typename __tree<_Tp, _Compare, _Allocator>::__node_holder
 __tree<_Tp, _Compare, _Allocator>::remove(const_iterator __p) _NOEXCEPT
 {
-    __node_pointer __np = const_cast<__node_pointer>(__p.__ptr_);
+    __node_pointer __np = __p.__ptr_;
     if (__begin_node() == __np)
     {
         if (__np->__right_ != nullptr)
diff --git a/include/algorithm b/include/algorithm
index 39191db97768..703a9b3dce1a 100644
--- a/include/algorithm
+++ b/include/algorithm
@@ -87,30 +87,63 @@ template <class InputIterator1, class InputIterator2>
     pair<InputIterator1, InputIterator2>
     mismatch(InputIterator1 first1, InputIterator1 last1, InputIterator2 first2);
 
+template <class InputIterator1, class InputIterator2>
+    pair<InputIterator1, InputIterator2>
+    mismatch(InputIterator1 first1, InputIterator1 last1, 
+             InputIterator2 first2, InputIterator2 last2); // **C++14**
+
 template <class InputIterator1, class InputIterator2, class BinaryPredicate>
     pair<InputIterator1, InputIterator2>
     mismatch(InputIterator1 first1, InputIterator1 last1,
              InputIterator2 first2, BinaryPredicate pred);
 
+template <class InputIterator1, class InputIterator2, class BinaryPredicate>
+    pair<InputIterator1, InputIterator2>
+    mismatch(InputIterator1 first1, InputIterator1 last1,
+             InputIterator2 first2, InputIterator2 last2,
+             BinaryPredicate pred); // **C++14**
+
 template <class InputIterator1, class InputIterator2>
     bool
     equal(InputIterator1 first1, InputIterator1 last1, InputIterator2 first2);
 
+template <class InputIterator1, class InputIterator2>
+    bool
+    equal(InputIterator1 first1, InputIterator1 last1, 
+          InputIterator2 first2, InputIterator2 last2); // **C++14**
+
 template <class InputIterator1, class InputIterator2, class BinaryPredicate>
     bool
     equal(InputIterator1 first1, InputIterator1 last1,
           InputIterator2 first2, BinaryPredicate pred);
 
+template <class InputIterator1, class InputIterator2, class BinaryPredicate>
+    bool
+    equal(InputIterator1 first1, InputIterator1 last1,
+          InputIterator2 first2, InputIterator2 last2,
+          BinaryPredicate pred); // **C++14**
+
 template<class ForwardIterator1, class ForwardIterator2>
     bool
     is_permutation(ForwardIterator1 first1, ForwardIterator1 last1,
                    ForwardIterator2 first2);
 
+template<class ForwardIterator1, class ForwardIterator2>
+    bool
+    is_permutation(ForwardIterator1 first1, ForwardIterator1 last1,
+                   ForwardIterator2 first2, ForwardIterator2 last2); // **C++14**
+
 template<class ForwardIterator1, class ForwardIterator2, class BinaryPredicate>
     bool
     is_permutation(ForwardIterator1 first1, ForwardIterator1 last1,
                    ForwardIterator2 first2, BinaryPredicate pred);
 
+template<class ForwardIterator1, class ForwardIterator2, class BinaryPredicate>
+    bool
+    is_permutation(ForwardIterator1 first1, ForwardIterator1 last1,
+                   ForwardIterator2 first2, ForwardIterator2 last2,
+                   BinaryPredicate pred);  // **C++14**
+
 template <class ForwardIterator1, class ForwardIterator2>
     ForwardIterator1
     search(ForwardIterator1 first1, ForwardIterator1 last1,
@@ -1087,6 +1120,32 @@ mismatch(_InputIterator1 __first1, _InputIterator1 __last1, _InputIterator2 __fi
     return _VSTD::mismatch(__first1, __last1, __first2, __equal_to<__v1, __v2>());
 }
 
+#if _LIBCPP_STD_VER > 11
+template <class _InputIterator1, class _InputIterator2, class _BinaryPredicate>
+inline _LIBCPP_INLINE_VISIBILITY
+pair<_InputIterator1, _InputIterator2>
+mismatch(_InputIterator1 __first1, _InputIterator1 __last1,
+         _InputIterator2 __first2, _InputIterator2 __last2,
+         _BinaryPredicate __pred)
+{
+    for (; __first1 != __last1 && __first2 != __last2; ++__first1, ++__first2)
+        if (!__pred(*__first1, *__first2))
+            break;
+    return pair<_InputIterator1, _InputIterator2>(__first1, __first2);
+}
+
+template <class _InputIterator1, class _InputIterator2>
+inline _LIBCPP_INLINE_VISIBILITY
+pair<_InputIterator1, _InputIterator2>
+mismatch(_InputIterator1 __first1, _InputIterator1 __last1,
+         _InputIterator2 __first2, _InputIterator2 __last2)
+{
+    typedef typename iterator_traits<_InputIterator1>::value_type __v1;
+    typedef typename iterator_traits<_InputIterator2>::value_type __v2;
+    return _VSTD::mismatch(__first1, __last1, __first2, __last2, __equal_to<__v1, __v2>());
+}
+#endif
+
 // equal
 
 template <class _InputIterator1, class _InputIterator2, class _BinaryPredicate>
@@ -1110,6 +1169,60 @@ equal(_InputIterator1 __first1, _InputIterator1 __last1, _InputIterator2 __first
     return _VSTD::equal(__first1, __last1, __first2, __equal_to<__v1, __v2>());
 }
 
+#if _LIBCPP_STD_VER > 11
+template <class _BinaryPredicate, class _InputIterator1, class _InputIterator2>
+inline _LIBCPP_INLINE_VISIBILITY
+bool
+__equal(_InputIterator1 __first1, _InputIterator1 __last1, 
+        _InputIterator2 __first2, _InputIterator2 __last2, _BinaryPredicate __pred,
+        input_iterator_tag, input_iterator_tag )
+{
+    for (; __first1 != __last1 && __first2 != __last2; ++__first1, ++__first2)
+        if (!__pred(*__first1, *__first2))
+            return false;
+    return __first1 == __last1 && __first2 == __last2;
+}
+
+template <class _BinaryPredicate, class _RandomAccessIterator1, class _RandomAccessIterator2>
+inline _LIBCPP_INLINE_VISIBILITY
+bool
+__equal(_RandomAccessIterator1 __first1, _RandomAccessIterator1 __last1, 
+        _RandomAccessIterator2 __first2, _RandomAccessIterator2 __last2, _BinaryPredicate __pred, 
+      random_access_iterator_tag, random_access_iterator_tag )
+{
+    if ( _VSTD::distance(__first1, __last1) != _VSTD::distance(__first2, __last2))
+        return false;
+    return _VSTD::equal<_RandomAccessIterator1, _RandomAccessIterator2,
+                        typename add_lvalue_reference<_BinaryPredicate>::type>
+                       (__first1, __last1, __first2, __pred );
+}
+
+template <class _InputIterator1, class _InputIterator2, class _BinaryPredicate>
+inline _LIBCPP_INLINE_VISIBILITY
+bool
+equal(_InputIterator1 __first1, _InputIterator1 __last1, 
+      _InputIterator2 __first2, _InputIterator2 __last2, _BinaryPredicate __pred )
+{
+    return _VSTD::__equal<typename add_lvalue_reference<_BinaryPredicate>::type>
+       (__first1, __last1, __first2, __last2, __pred, 
+        typename iterator_traits<_InputIterator1>::iterator_category(),
+        typename iterator_traits<_InputIterator2>::iterator_category());
+}
+
+template <class _InputIterator1, class _InputIterator2>
+inline _LIBCPP_INLINE_VISIBILITY
+bool
+equal(_InputIterator1 __first1, _InputIterator1 __last1, 
+      _InputIterator2 __first2, _InputIterator2 __last2)
+{
+    typedef typename iterator_traits<_InputIterator1>::value_type __v1;
+    typedef typename iterator_traits<_InputIterator2>::value_type __v2;
+    return _VSTD::__equal(__first1, __last1, __first2, __last2, __equal_to<__v1, __v2>(),
+        typename iterator_traits<_InputIterator1>::iterator_category(),
+        typename iterator_traits<_InputIterator2>::iterator_category());
+}
+#endif
+
 // is_permutation
 
 template<class _ForwardIterator1, class _ForwardIterator2, class _BinaryPredicate>
@@ -1169,6 +1282,100 @@ is_permutation(_ForwardIterator1 __first1, _ForwardIterator1 __last1,
     return _VSTD::is_permutation(__first1, __last1, __first2, __equal_to<__v1, __v2>());
 }
 
+#if _LIBCPP_STD_VER > 11
+template<class _BinaryPredicate, class _ForwardIterator1, class _ForwardIterator2>
+bool
+__is_permutation(_ForwardIterator1 __first1, _ForwardIterator1 __last1,
+                 _ForwardIterator2 __first2, _ForwardIterator2 __last2, 
+                 _BinaryPredicate __pred,
+                 forward_iterator_tag, forward_iterator_tag )
+{
+    // shorten sequences as much as possible by lopping of any equal parts
+    for (; __first1 != __last1 && __first2 != __last2; ++__first1, ++__first2)
+        if (!__pred(*__first1, *__first2))
+            goto __not_done;
+    return __first1 == __last1 && __first2 == __last2;
+__not_done:
+    // __first1 != __last1 && __first2 != __last2 && *__first1 != *__first2
+    typedef typename iterator_traits<_ForwardIterator1>::difference_type _D1;
+    _D1 __l1 = _VSTD::distance(__first1, __last1);
+
+    typedef typename iterator_traits<_ForwardIterator2>::difference_type _D2;
+    _D2 __l2 = _VSTD::distance(__first2, __last2);
+    if (__l1 != __l2)
+        return false;
+
+    // For each element in [f1, l1) see if there are the same number of
+    //    equal elements in [f2, l2)
+    for (_ForwardIterator1 __i = __first1; __i != __last1; ++__i)
+    {
+        // Have we already counted the number of *__i in [f1, l1)?
+        for (_ForwardIterator1 __j = __first1; __j != __i; ++__j)
+            if (__pred(*__j, *__i))
+                goto __next_iter;
+        {
+            // Count number of *__i in [f2, l2)
+            _D1 __c2 = 0;
+            for (_ForwardIterator2 __j = __first2; __j != __last2; ++__j)
+                if (__pred(*__i, *__j))
+                    ++__c2;
+            if (__c2 == 0)
+                return false;
+            // Count number of *__i in [__i, l1) (we can start with 1)
+            _D1 __c1 = 1;
+            for (_ForwardIterator1 __j = _VSTD::next(__i); __j != __last1; ++__j)
+                if (__pred(*__i, *__j))
+                    ++__c1;
+            if (__c1 != __c2)
+                return false;
+        }
+__next_iter:;
+    }
+    return true;
+}
+
+template<class _BinaryPredicate, class _RandomAccessIterator1, class _RandomAccessIterator2>
+bool
+__is_permutation(_RandomAccessIterator1 __first1, _RandomAccessIterator2 __last1,
+               _RandomAccessIterator1 __first2, _RandomAccessIterator2 __last2, 
+               _BinaryPredicate __pred,
+               random_access_iterator_tag, random_access_iterator_tag )
+{
+    if ( _VSTD::distance(__first1, __last1) != _VSTD::distance(__first2, __last2))
+        return false;
+    return _VSTD::is_permutation<_RandomAccessIterator1, _RandomAccessIterator2,
+                                 typename add_lvalue_reference<_BinaryPredicate>::type>
+                                (__first1, __last1, __first2, __pred );
+}
+
+template<class _ForwardIterator1, class _ForwardIterator2, class _BinaryPredicate>
+inline _LIBCPP_INLINE_VISIBILITY
+bool
+is_permutation(_ForwardIterator1 __first1, _ForwardIterator1 __last1,
+               _ForwardIterator2 __first2, _ForwardIterator2 __last2,
+               _BinaryPredicate __pred )
+{
+    return _VSTD::__is_permutation<typename add_lvalue_reference<_BinaryPredicate>::type>
+       (__first1, __last1, __first2, __last2, __pred,
+        typename iterator_traits<_ForwardIterator1>::iterator_category(),
+        typename iterator_traits<_ForwardIterator2>::iterator_category());
+}
+
+template<class _ForwardIterator1, class _ForwardIterator2>
+inline _LIBCPP_INLINE_VISIBILITY
+bool
+is_permutation(_ForwardIterator1 __first1, _ForwardIterator1 __last1,
+               _ForwardIterator2 __first2, _ForwardIterator2 __last2)
+{
+    typedef typename iterator_traits<_ForwardIterator1>::value_type __v1;
+    typedef typename iterator_traits<_ForwardIterator2>::value_type __v2;
+    return _VSTD::__is_permutation(__first1, __last1, __first2, __last2,
+        __equal_to<__v1, __v2>(),
+        typename iterator_traits<_ForwardIterator1>::iterator_category(),
+        typename iterator_traits<_ForwardIterator2>::iterator_category());
+}
+#endif
+
 // search
 
 template <class _BinaryPredicate, class _ForwardIterator1, class _ForwardIterator2>
diff --git a/include/atomic b/include/atomic
index db67e7625b81..f6ab1cbaf49f 100644
--- a/include/atomic
+++ b/include/atomic
@@ -622,7 +622,12 @@ struct __atomic_base  // false
         {return __c11_atomic_compare_exchange_strong(&__a_, &__e, __d, __m, __m);}
 
     _LIBCPP_INLINE_VISIBILITY
-    __atomic_base() _NOEXCEPT {} // = default;
+#ifndef _LIBCPP_HAS_NO_DEFAULTED_FUNCTIONS
+    __atomic_base() _NOEXCEPT = default;
+#else
+    __atomic_base() _NOEXCEPT : __a_() {}
+#endif // _LIBCPP_HAS_NO_DEFAULTED_FUNCTIONS
+
     _LIBCPP_INLINE_VISIBILITY
     _LIBCPP_CONSTEXPR __atomic_base(_Tp __d) _NOEXCEPT : __a_(__d) {}
 #ifndef _LIBCPP_HAS_NO_DELETED_FUNCTIONS
@@ -645,7 +650,7 @@ struct __atomic_base<_Tp, true>
 {
     typedef __atomic_base<_Tp, false> __base;
     _LIBCPP_INLINE_VISIBILITY
-    __atomic_base() _NOEXCEPT {} // = default;
+    __atomic_base() _NOEXCEPT _LIBCPP_DEFAULT
     _LIBCPP_INLINE_VISIBILITY
     _LIBCPP_CONSTEXPR __atomic_base(_Tp __d) _NOEXCEPT : __base(__d) {}
 
@@ -726,7 +731,7 @@ struct atomic
 {
     typedef __atomic_base<_Tp> __base;
     _LIBCPP_INLINE_VISIBILITY
-    atomic() _NOEXCEPT {} // = default;
+    atomic() _NOEXCEPT _LIBCPP_DEFAULT
     _LIBCPP_INLINE_VISIBILITY
     _LIBCPP_CONSTEXPR atomic(_Tp __d) _NOEXCEPT : __base(__d) {}
 
@@ -746,7 +751,7 @@ struct atomic<_Tp*>
 {
     typedef __atomic_base<_Tp*> __base;
     _LIBCPP_INLINE_VISIBILITY
-    atomic() _NOEXCEPT {} // = default;
+    atomic() _NOEXCEPT _LIBCPP_DEFAULT
     _LIBCPP_INLINE_VISIBILITY
     _LIBCPP_CONSTEXPR atomic(_Tp* __d) _NOEXCEPT : __base(__d) {}
 
@@ -1367,7 +1372,12 @@ typedef struct atomic_flag
         {__c11_atomic_store(&__a_, false, __m);}
 
     _LIBCPP_INLINE_VISIBILITY
-    atomic_flag() _NOEXCEPT {} // = default;
+#ifndef _LIBCPP_HAS_NO_DEFAULTED_FUNCTIONS
+    atomic_flag() _NOEXCEPT = default;
+#else
+    atomic_flag() _NOEXCEPT : __a_() {}
+#endif // _LIBCPP_HAS_NO_DEFAULTED_FUNCTIONS
+
     _LIBCPP_INLINE_VISIBILITY
     atomic_flag(bool __b) _NOEXCEPT : __a_(__b) {}
 
diff --git a/include/chrono b/include/chrono
index 3b96e8164e5f..4ceb875c3f02 100644
--- a/include/chrono
+++ b/include/chrono
@@ -468,7 +468,7 @@ template <class _LhsDuration, class _RhsDuration>
 struct __duration_eq
 {
     _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR
-    bool operator()(const _LhsDuration& __lhs, const _RhsDuration& __rhs)
+    bool operator()(const _LhsDuration& __lhs, const _RhsDuration& __rhs) const
         {
             typedef typename common_type<_LhsDuration, _RhsDuration>::type _Ct;
             return _Ct(__lhs).count() == _Ct(__rhs).count();
@@ -479,7 +479,7 @@ template <class _LhsDuration>
 struct __duration_eq<_LhsDuration, _LhsDuration>
 {
     _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR
-    bool operator()(const _LhsDuration& __lhs, const _LhsDuration& __rhs)
+    bool operator()(const _LhsDuration& __lhs, const _LhsDuration& __rhs) const
         {return __lhs.count() == __rhs.count();}
 };
 
@@ -509,7 +509,7 @@ template <class _LhsDuration, class _RhsDuration>
 struct __duration_lt
 {
     _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR
-    bool operator()(const _LhsDuration& __lhs, const _RhsDuration& __rhs)
+    bool operator()(const _LhsDuration& __lhs, const _RhsDuration& __rhs) const
         {
             typedef typename common_type<_LhsDuration, _RhsDuration>::type _Ct;
             return _Ct(__lhs).count() < _Ct(__rhs).count();
@@ -520,7 +520,7 @@ template <class _LhsDuration>
 struct __duration_lt<_LhsDuration, _LhsDuration>
 {
     _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR
-    bool operator()(const _LhsDuration& __lhs, const _LhsDuration& __rhs)
+    bool operator()(const _LhsDuration& __lhs, const _LhsDuration& __rhs) const
         {return __lhs.count() < __rhs.count();}
 };
 
diff --git a/include/deque b/include/deque
index 8e098223d258..6c0216d7ecb8 100644
--- a/include/deque
+++ b/include/deque
@@ -915,7 +915,14 @@ protected:
                                                          __pointer_allocator;
     typedef allocator_traits<__pointer_allocator>        __map_traits;
     typedef typename __map_traits::pointer               __map_pointer;
-    typedef typename __map_traits::const_pointer         __map_const_pointer;
+    typedef typename __alloc_traits::template
+#ifndef _LIBCPP_HAS_NO_TEMPLATE_ALIASES
+                rebind_alloc<const_pointer>
+#else
+                rebind_alloc<const_pointer>::other
+#endif
+                                                         __const_pointer_allocator;
+    typedef typename allocator_traits<__const_pointer_allocator>::const_pointer __map_const_pointer;
     typedef __split_buffer<pointer, __pointer_allocator> __map;
 
     typedef __deque_iterator<value_type, pointer, reference, __map_pointer,
@@ -1053,7 +1060,7 @@ template <class _Tp, class _Allocator>
 typename __deque_base<_Tp, _Allocator>::const_iterator
 __deque_base<_Tp, _Allocator>::begin() const _NOEXCEPT
 {
-    __map_const_pointer __mp = __map_.begin() + __start_ / __block_size;
+    __map_const_pointer __mp = static_cast<__map_const_pointer>(__map_.begin() + __start_ / __block_size);
     return const_iterator(__mp, __map_.empty() ? 0 : *__mp + __start_ % __block_size);
 }
 
@@ -1071,7 +1078,7 @@ typename __deque_base<_Tp, _Allocator>::const_iterator
 __deque_base<_Tp, _Allocator>::end() const _NOEXCEPT
 {
     size_type __p = size() + __start_;
-    __map_const_pointer __mp = __map_.begin() + __p / __block_size;
+    __map_const_pointer __mp = static_cast<__map_const_pointer>(__map_.begin() + __p / __block_size);
     return const_iterator(__mp, __map_.empty() ? 0 : *__mp + __p % __block_size);
 }
 
@@ -1341,6 +1348,8 @@ public:
     _LIBCPP_INLINE_VISIBILITY
     bool __invariants() const {return __base::__invariants();}
 private:
+    typedef typename __base::__map_const_pointer __map_const_pointer;
+
     _LIBCPP_INLINE_VISIBILITY
     static size_type __recommend_blocks(size_type __n)
     {
@@ -2505,9 +2514,9 @@ void
 deque<_Tp, _Allocator>::pop_front()
 {
     allocator_type& __a = __base::__alloc();
-    __alloc_traits::destroy(__a, *(__base::__map_.begin() +
-                                   __base::__start_ / __base::__block_size) +
-                                   __base::__start_ % __base::__block_size);
+    __alloc_traits::destroy(__a, __to_raw_pointer(*(__base::__map_.begin() +
+                                                    __base::__start_ / __base::__block_size) +
+                                                    __base::__start_ % __base::__block_size));
     --__base::size();
     if (++__base::__start_ >= 2 * __base::__block_size)
     {
@@ -2523,9 +2532,9 @@ deque<_Tp, _Allocator>::pop_back()
 {
     allocator_type& __a = __base::__alloc();
     size_type __p = __base::size() + __base::__start_ - 1;
-    __alloc_traits::destroy(__a, *(__base::__map_.begin() +
-                                   __p / __base::__block_size) +
-                                   __p % __base::__block_size);
+    __alloc_traits::destroy(__a, __to_raw_pointer(*(__base::__map_.begin() +
+                                                    __p / __base::__block_size) +
+                                                    __p % __base::__block_size));
     --__base::size();
     if (__back_spare() >= 2 * __base::__block_size)
     {
@@ -2556,7 +2565,7 @@ deque<_Tp, _Allocator>::__move_and_check(iterator __f, iterator __l, iterator __
             __fe = __fb + __bs;
         }
         if (__fb <= __vt && __vt < __fe)
-            __vt = (const_iterator(__f.__m_iter_, __vt) -= __f - __r).__ptr_;
+            __vt = (const_iterator(static_cast<__map_const_pointer>(__f.__m_iter_), __vt) -= __f - __r).__ptr_;
         __r = _VSTD::move(__fb, __fe, __r);
         __n -= __bs;
         __f += __bs;
@@ -2587,7 +2596,7 @@ deque<_Tp, _Allocator>::__move_backward_and_check(iterator __f, iterator __l, it
             __lb = __le - __bs;
         }
         if (__lb <= __vt && __vt < __le)
-            __vt = (const_iterator(__l.__m_iter_, __vt) += __r - __l - 1).__ptr_;
+            __vt = (const_iterator(static_cast<__map_const_pointer>(__l.__m_iter_), __vt) += __r - __l - 1).__ptr_;
         __r = _VSTD::move_backward(__lb, __le, __r);
         __n -= __bs;
         __l -= __bs - 1;
@@ -2618,7 +2627,7 @@ deque<_Tp, _Allocator>::__move_construct_and_check(iterator __f, iterator __l,
             __fe = __fb + __bs;
         }
         if (__fb <= __vt && __vt < __fe)
-            __vt = (const_iterator(__f.__m_iter_, __vt) += __r - __f).__ptr_;
+            __vt = (const_iterator(static_cast<__map_const_pointer>(__f.__m_iter_), __vt) += __r - __f).__ptr_;
         for (; __fb != __fe; ++__fb, ++__r, ++__base::size())
             __alloc_traits::construct(__a, _VSTD::addressof(*__r), _VSTD::move(*__fb));
         __n -= __bs;
@@ -2654,7 +2663,7 @@ deque<_Tp, _Allocator>::__move_construct_backward_and_check(iterator __f, iterat
             __lb = __le - __bs;
         }
         if (__lb <= __vt && __vt < __le)
-            __vt = (const_iterator(__l.__m_iter_, __vt) -= __l - __r + 1).__ptr_;
+            __vt = (const_iterator(static_cast<__map_const_pointer>(__l.__m_iter_), __vt) -= __l - __r + 1).__ptr_;
         while (__le != __lb)
         {
             __alloc_traits::construct(__a, _VSTD::addressof(*--__r), _VSTD::move(*--__le));
diff --git a/include/forward_list b/include/forward_list
index 0cbf2fdb632f..88bf75f90d7c 100644
--- a/include/forward_list
+++ b/include/forward_list
@@ -232,7 +232,7 @@ public:
     typedef forward_iterator_tag                              iterator_category;
     typedef typename pointer_traits<__node_pointer>::element_type::value_type
                                                               value_type;
-    typedef value_type& reference;
+    typedef value_type&                                       reference;
     typedef typename pointer_traits<__node_pointer>::difference_type
                                                               difference_type;
     typedef typename pointer_traits<__node_pointer>::template
@@ -249,7 +249,7 @@ public:
     _LIBCPP_INLINE_VISIBILITY
     reference operator*() const {return __ptr_->__value_;}
     _LIBCPP_INLINE_VISIBILITY
-    pointer operator->() const {return &__ptr_->__value_;}
+    pointer operator->() const {return pointer_traits<pointer>::pointer_to(__ptr_->__value_);}
 
     _LIBCPP_INLINE_VISIBILITY
     __forward_list_iterator& operator++()
@@ -303,7 +303,7 @@ class _LIBCPP_TYPE_VIS __forward_list_const_iterator
 public:
     typedef forward_iterator_tag                              iterator_category;
     typedef typename __node::value_type                       value_type;
-    typedef const value_type& reference;
+    typedef const value_type&                                 reference;
     typedef typename pointer_traits<__node_const_pointer>::difference_type
                                                               difference_type;
     typedef typename pointer_traits<__node_const_pointer>::template
@@ -323,7 +323,7 @@ public:
     _LIBCPP_INLINE_VISIBILITY
     reference operator*() const {return __ptr_->__value_;}
     _LIBCPP_INLINE_VISIBILITY
-    pointer operator->() const {return &__ptr_->__value_;}
+    pointer operator->() const {return pointer_traits<pointer>::pointer_to(__ptr_->__value_);}
 
     _LIBCPP_INLINE_VISIBILITY
     __forward_list_const_iterator& operator++()
@@ -368,18 +368,27 @@ protected:
                                                       __node_allocator;
     typedef allocator_traits<__node_allocator>        __node_traits;
     typedef typename __node_traits::pointer           __node_pointer;
-    typedef typename __node_traits::const_pointer     __node_const_pointer;
+    typedef typename __node_traits::pointer           __node_const_pointer;
+
+    typedef typename allocator_traits<allocator_type>::template
+#ifndef _LIBCPP_HAS_NO_TEMPLATE_ALIASES
+                rebind_alloc<__begin_node>
+#else
+                rebind_alloc<__begin_node>::other
+#endif
+                                                      __begin_node_allocator;
+    typedef typename allocator_traits<__begin_node_allocator>::pointer __begin_node_pointer;
 
     __compressed_pair<__begin_node, __node_allocator> __before_begin_;
 
     _LIBCPP_INLINE_VISIBILITY
     __node_pointer        __before_begin() _NOEXCEPT
-        {return pointer_traits<__node_pointer>::pointer_to(
-                                static_cast<__node&>(__before_begin_.first()));}
+        {return static_cast<__node_pointer>(pointer_traits<__begin_node_pointer>::
+                                        pointer_to(__before_begin_.first()));}
     _LIBCPP_INLINE_VISIBILITY
     __node_const_pointer  __before_begin() const _NOEXCEPT
-        {return pointer_traits<__node_const_pointer>::pointer_to(
-                          static_cast<const __node&>(__before_begin_.first()));}
+        {return static_cast<__node_const_pointer>(pointer_traits<__begin_node_pointer>::
+                                        pointer_to(const_cast<__begin_node&>(__before_begin_.first())));}
 
     _LIBCPP_INLINE_VISIBILITY
           __node_allocator& __alloc() _NOEXCEPT
@@ -389,7 +398,7 @@ protected:
         {return __before_begin_.second();}
 
     typedef __forward_list_iterator<__node_pointer>             iterator;
-    typedef __forward_list_const_iterator<__node_const_pointer> const_iterator;
+    typedef __forward_list_const_iterator<__node_pointer>       const_iterator;
 
     _LIBCPP_INLINE_VISIBILITY
     __forward_list_base()
@@ -1050,7 +1059,7 @@ template <class... _Args>
 typename forward_list<_Tp, _Alloc>::iterator
 forward_list<_Tp, _Alloc>::emplace_after(const_iterator __p, _Args&&... __args)
 {
-    __node_pointer const __r = const_cast<__node_pointer>(__p.__ptr_);
+    __node_pointer const __r = __p.__ptr_;
     __node_allocator& __a = base::__alloc();
     typedef __allocator_destructor<__node_allocator> _Dp;
     unique_ptr<__node, _Dp> __h(__node_traits::allocate(__a, 1), _Dp(__a, 1));
@@ -1067,7 +1076,7 @@ template <class _Tp, class _Alloc>
 typename forward_list<_Tp, _Alloc>::iterator
 forward_list<_Tp, _Alloc>::insert_after(const_iterator __p, value_type&& __v)
 {
-    __node_pointer const __r = const_cast<__node_pointer>(__p.__ptr_);
+    __node_pointer const __r = __p.__ptr_;
     __node_allocator& __a = base::__alloc();
     typedef __allocator_destructor<__node_allocator> _Dp;
     unique_ptr<__node, _Dp> __h(__node_traits::allocate(__a, 1), _Dp(__a, 1));
@@ -1083,7 +1092,7 @@ template <class _Tp, class _Alloc>
 typename forward_list<_Tp, _Alloc>::iterator
 forward_list<_Tp, _Alloc>::insert_after(const_iterator __p, const value_type& __v)
 {
-    __node_pointer const __r = const_cast<__node_pointer>(__p.__ptr_);
+    __node_pointer const __r = __p.__ptr_;
     __node_allocator& __a = base::__alloc();
     typedef __allocator_destructor<__node_allocator> _Dp;
     unique_ptr<__node, _Dp> __h(__node_traits::allocate(__a, 1), _Dp(__a, 1));
@@ -1098,7 +1107,7 @@ typename forward_list<_Tp, _Alloc>::iterator
 forward_list<_Tp, _Alloc>::insert_after(const_iterator __p, size_type __n,
                                         const value_type& __v)
 {
-    __node_pointer __r = const_cast<__node_pointer>(__p.__ptr_);
+    __node_pointer __r = __p.__ptr_;
     if (__n > 0)
     {
         __node_allocator& __a = base::__alloc();
@@ -1148,7 +1157,7 @@ typename enable_if
 forward_list<_Tp, _Alloc>::insert_after(const_iterator __p,
                                         _InputIterator __f, _InputIterator __l)
 {
-    __node_pointer __r = const_cast<__node_pointer>(__p.__ptr_);
+    __node_pointer __r = __p.__ptr_;
     if (__f != __l)
     {
         __node_allocator& __a = base::__alloc();
@@ -1192,7 +1201,7 @@ template <class _Tp, class _Alloc>
 typename forward_list<_Tp, _Alloc>::iterator
 forward_list<_Tp, _Alloc>::erase_after(const_iterator __f)
 {
-    __node_pointer __p = const_cast<__node_pointer>(__f.__ptr_);
+    __node_pointer __p = __f.__ptr_;
     __node_pointer __n = __p->__next_;
     __p->__next_ = __n->__next_;
     __node_allocator& __a = base::__alloc();
@@ -1205,10 +1214,10 @@ template <class _Tp, class _Alloc>
 typename forward_list<_Tp, _Alloc>::iterator
 forward_list<_Tp, _Alloc>::erase_after(const_iterator __f, const_iterator __l)
 {
-    __node_pointer __e = const_cast<__node_pointer>(__l.__ptr_);
+    __node_pointer __e = __l.__ptr_;
     if (__f != __l)
     {
-        __node_pointer __p = const_cast<__node_pointer>(__f.__ptr_);
+        __node_pointer __p = __f.__ptr_;
         __node_pointer __n = __p->__next_;
         if (__n != __e)
         {
@@ -1302,12 +1311,10 @@ forward_list<_Tp, _Alloc>::splice_after(const_iterator __p,
             const_iterator __lm1 = __x.before_begin();
             while (__lm1.__ptr_->__next_ != nullptr)
                 ++__lm1;
-            const_cast<__node_pointer>(__lm1.__ptr_)->__next_ =
-                const_cast<__node_pointer>(__p.__ptr_)->__next_;
+            __lm1.__ptr_->__next_ = __p.__ptr_->__next_;
         }
-        const_cast<__node_pointer>(__p.__ptr_)->__next_ =
-            const_cast<__node_pointer>(__x.__before_begin())->__next_;
-        const_cast<__node_pointer>(__x.__before_begin())->__next_ = nullptr;
+        __p.__ptr_->__next_ = __x.__before_begin()->__next_;
+        __x.__before_begin()->__next_ = nullptr;
     }
 }
 
@@ -1320,12 +1327,9 @@ forward_list<_Tp, _Alloc>::splice_after(const_iterator __p,
     const_iterator __lm1 = _VSTD::next(__i);
     if (__p != __i && __p != __lm1)
     {
-        const_cast<__node_pointer>(__i.__ptr_)->__next_ =
-            const_cast<__node_pointer>(__lm1.__ptr_)->__next_;
-        const_cast<__node_pointer>(__lm1.__ptr_)->__next_ =
-            const_cast<__node_pointer>(__p.__ptr_)->__next_;
-        const_cast<__node_pointer>(__p.__ptr_)->__next_ =
-            const_cast<__node_pointer>(__lm1.__ptr_);
+        __i.__ptr_->__next_ = __lm1.__ptr_->__next_;
+        __lm1.__ptr_->__next_ = __p.__ptr_->__next_;
+        __p.__ptr_->__next_ = __lm1.__ptr_;
     }
 }
 
@@ -1342,12 +1346,9 @@ forward_list<_Tp, _Alloc>::splice_after(const_iterator __p,
             ++__lm1;
         if (__f != __lm1)
         {
-            const_cast<__node_pointer>(__lm1.__ptr_)->__next_ =
-                const_cast<__node_pointer>(__p.__ptr_)->__next_;
-            const_cast<__node_pointer>(__p.__ptr_)->__next_ =
-                const_cast<__node_pointer>(__f.__ptr_)->__next_;
-            const_cast<__node_pointer>(__f.__ptr_)->__next_ =
-                const_cast<__node_pointer>(__l.__ptr_);
+            __lm1.__ptr_->__next_ = __p.__ptr_->__next_;
+            __p.__ptr_->__next_ = __f.__ptr_->__next_;
+            __f.__ptr_->__next_ = __l.__ptr_;
         }
     }
 }
diff --git a/include/functional b/include/functional
index 995db564c1d7..d1a6301fb876 100644
--- a/include/functional
+++ b/include/functional
@@ -1139,8 +1139,11 @@ public:
     function(const function&);
     function(function&&) _NOEXCEPT;
     template<class _Fp>
-      function(_Fp,
-               typename enable_if<__callable<_Fp>::value>::type* = 0);
+      function(_Fp, typename enable_if
+                                     <
+                                        __callable<_Fp>::value &&
+                                        !is_same<_Fp, function>::value
+                                      >::type* = 0);
 
     template<class _Alloc>
       _LIBCPP_INLINE_VISIBILITY
@@ -1162,7 +1165,8 @@ public:
     template<class _Fp>
       typename enable_if
       <
-        __callable<typename decay<_Fp>::type>::value,
+        __callable<typename decay<_Fp>::type>::value &&
+        !is_same<typename remove_reference<_Fp>::type, function>::value,
         function&
       >::type
       operator=(_Fp&&);
@@ -1266,7 +1270,11 @@ function<_Rp(_ArgTypes...)>::function(allocator_arg_t, const _Alloc&,
 template<class _Rp, class ..._ArgTypes>
 template <class _Fp>
 function<_Rp(_ArgTypes...)>::function(_Fp __f,
-                                     typename enable_if<__callable<_Fp>::value>::type*)
+                                     typename enable_if
+                                     <
+                                        __callable<_Fp>::value &&
+                                        !is_same<_Fp, function>::value
+                                     >::type*)
     : __f_(0)
 {
     if (__not_null(__f))
@@ -1370,7 +1378,8 @@ template<class _Rp, class ..._ArgTypes>
 template <class _Fp>
 typename enable_if
 <
-    function<_Rp(_ArgTypes...)>::template __callable<typename decay<_Fp>::type>::value,
+    function<_Rp(_ArgTypes...)>::template __callable<typename decay<_Fp>::type>::value &&
+    !is_same<typename remove_reference<_Fp>::type, function<_Rp(_ArgTypes...)>>::value,
     function<_Rp(_ArgTypes...)>&
 >::type
 function<_Rp(_ArgTypes...)>::operator=(_Fp&& __f)
@@ -1594,12 +1603,24 @@ template <class _Ti, bool IsReferenceWrapper, bool IsBindEx, bool IsPh,
           class _TupleUj>
 struct ____mu_return;
 
+template <bool _Invokable, class _Ti, class ..._Uj>
+struct ____mu_return_invokable  // false
+{
+    typedef __nat type;
+};
+
 template <class _Ti, class ..._Uj>
-struct ____mu_return<_Ti, false, true, false, tuple<_Uj...> >
+struct ____mu_return_invokable<true, _Ti, _Uj...>
 {
     typedef typename __invoke_of<_Ti&, _Uj...>::type type;
 };
 
+template <class _Ti, class ..._Uj>
+struct ____mu_return<_Ti, false, true, false, tuple<_Uj...> >
+    : public ____mu_return_invokable<__invokable<_Ti&, _Uj...>::value, _Ti, _Uj...>
+{
+};
+
 template <class _Ti, class _TupleUj>
 struct ____mu_return<_Ti, false, false, true, _TupleUj>
 {
@@ -1737,7 +1758,9 @@ public:
     template <class _Gp, class ..._BA,
               class = typename enable_if
                                <
-                                  is_constructible<_Fd, _Gp>::value
+                                  is_constructible<_Fd, _Gp>::value &&
+                                  !is_same<typename remove_reference<_Gp>::type,
+                                           __bind>::value
                                >::type>
       _LIBCPP_INLINE_VISIBILITY
       explicit __bind(_Gp&& __f, _BA&& ...__bound_args)
@@ -1802,7 +1825,13 @@ public:
 
 #endif  // _LIBCPP_HAS_NO_DEFAULTED_FUNCTIONS
 
-    template <class _Gp, class ..._BA>
+    template <class _Gp, class ..._BA,
+              class = typename enable_if
+                               <
+                                  is_constructible<_Fd, _Gp>::value &&
+                                  !is_same<typename remove_reference<_Gp>::type,
+                                           __bind_r>::value
+                               >::type>
       _LIBCPP_INLINE_VISIBILITY
       explicit __bind_r(_Gp&& __f, _BA&& ...__bound_args)
         : base(_VSTD::forward<_Gp>(__f),
diff --git a/include/future b/include/future
index 3d7bb6c9d045..dae1a4b805ec 100644
--- a/include/future
+++ b/include/future
@@ -403,6 +403,72 @@ _LIBCPP_DECLARE_STRONG_ENUM(launch)
 };
 _LIBCPP_DECLARE_STRONG_ENUM_EPILOG(launch)
 
+#ifndef _LIBCPP_HAS_NO_STRONG_ENUMS
+
+#ifdef _LIBCXX_UNDERLYING_TYPE
+typedef underlying_type<launch>::type __launch_underlying_type;
+#else
+typedef int __launch_underlying_type;
+#endif
+
+inline _LIBCPP_INLINE_VISIBILITY
+_LIBCPP_CONSTEXPR
+launch
+operator&(launch __x, launch __y)
+{
+    return static_cast<launch>(static_cast<__launch_underlying_type>(__x) &
+                               static_cast<__launch_underlying_type>(__y));
+}
+
+inline _LIBCPP_INLINE_VISIBILITY
+_LIBCPP_CONSTEXPR
+launch
+operator|(launch __x, launch __y)
+{
+    return static_cast<launch>(static_cast<__launch_underlying_type>(__x) |
+                               static_cast<__launch_underlying_type>(__y));
+}
+
+inline _LIBCPP_INLINE_VISIBILITY
+_LIBCPP_CONSTEXPR
+launch
+operator^(launch __x, launch __y)
+{
+    return static_cast<launch>(static_cast<__launch_underlying_type>(__x) ^
+                               static_cast<__launch_underlying_type>(__y));
+}
+
+inline _LIBCPP_INLINE_VISIBILITY
+_LIBCPP_CONSTEXPR
+launch
+operator~(launch __x)
+{
+    return static_cast<launch>(~static_cast<__launch_underlying_type>(__x) & 3);
+}
+
+inline _LIBCPP_INLINE_VISIBILITY
+launch&
+operator&=(launch& __x, launch __y)
+{
+    __x = __x & __y; return __x;
+}
+
+inline _LIBCPP_INLINE_VISIBILITY
+launch&
+operator|=(launch& __x, launch __y)
+{
+    __x = __x | __y; return __x;
+}
+
+inline _LIBCPP_INLINE_VISIBILITY
+launch&
+operator^=(launch& __x, launch __y)
+{
+    __x = __x ^ __y; return __x;
+}
+
+#endif  // !_LIBCPP_HAS_NO_STRONG_ENUMS
+
 //enum class future_status
 _LIBCPP_DECLARE_STRONG_ENUM(future_status)
 {
diff --git a/include/istream b/include/istream
index 3f629f68008c..f3e74c382e6b 100644
--- a/include/istream
+++ b/include/istream
@@ -1144,8 +1144,7 @@ basic_istream<_CharT, _Traits>::ignore(streamsize __n, int_type __dlm)
                        break;
                     }
                     ++__gc_;
-                    char_type __ch = traits_type::to_char_type(__i);
-                    if (traits_type::eq(__ch, static_cast<char_type>(__dlm)))
+                    if (traits_type::eq_int_type(__i, __dlm))
                         break;
                 }
             }
@@ -1160,8 +1159,7 @@ basic_istream<_CharT, _Traits>::ignore(streamsize __n, int_type __dlm)
                        break;
                     }
                     ++__gc_;
-                    char_type __ch = traits_type::to_char_type(__i);
-                    if (traits_type::eq(__ch, static_cast<char_type>(__dlm)))
+                    if (traits_type::eq_int_type(__i, __dlm))
                         break;
                 }
             }
diff --git a/include/iterator b/include/iterator
index 3b078a2a214c..dda053da33bc 100644
--- a/include/iterator
+++ b/include/iterator
@@ -1135,7 +1135,14 @@ public:
 #endif
         return *__i;
     }
-    _LIBCPP_INLINE_VISIBILITY pointer  operator->() const _NOEXCEPT {return &(operator*());}
+    _LIBCPP_INLINE_VISIBILITY pointer  operator->() const _NOEXCEPT
+    {
+#if _LIBCPP_DEBUG_LEVEL >= 2
+        _LIBCPP_ASSERT(__get_const_db()->__dereferenceable(this),
+                       "Attempted to dereference a non-dereferenceable iterator");
+#endif
+        return (pointer)&reinterpret_cast<const volatile char&>(*__i);
+    }
     _LIBCPP_INLINE_VISIBILITY __wrap_iter& operator++() _NOEXCEPT
     {
 #if _LIBCPP_DEBUG_LEVEL >= 2
diff --git a/include/list b/include/list
index c6000c972653..628a35bade72 100644
--- a/include/list
+++ b/include/list
@@ -196,13 +196,20 @@ struct __list_node_base
         rebind<__list_node<_Tp, _VoidPtr> >::other pointer;
 #endif
 
+    typedef typename pointer_traits<_VoidPtr>::template
+#ifndef _LIBCPP_HAS_NO_TEMPLATE_ALIASES
+        rebind<__list_node_base> __base_pointer;
+#else
+        rebind<__list_node_base>::other __base_pointer;
+#endif
+
     pointer __prev_;
     pointer __next_;
 
     _LIBCPP_INLINE_VISIBILITY
     __list_node_base()
-        : __prev_(static_cast<pointer>(this)),
-          __next_(static_cast<pointer>(this))
+        : __prev_(static_cast<pointer>(pointer_traits<__base_pointer>::pointer_to(*this))),
+          __next_(static_cast<pointer>(pointer_traits<__base_pointer>::pointer_to(*this)))
           {}
 };
 
@@ -305,7 +312,14 @@ public:
         return __ptr_->__value_;
     }
     _LIBCPP_INLINE_VISIBILITY
-    pointer operator->() const {return &(operator*());}
+    pointer operator->() const
+    {
+#if _LIBCPP_DEBUG_LEVEL >= 2
+        _LIBCPP_ASSERT(__get_const_db()->__dereferenceable(this),
+                       "Attempted to dereference a non-dereferenceable list::iterator");
+#endif
+        return pointer_traits<pointer>::pointer_to(__ptr_->__value_);
+    }
 
     _LIBCPP_INLINE_VISIBILITY
     __list_iterator& operator++()
@@ -352,9 +366,9 @@ class _LIBCPP_TYPE_VIS __list_const_iterator
 {
     typedef typename pointer_traits<_VoidPtr>::template
 #ifndef _LIBCPP_HAS_NO_TEMPLATE_ALIASES
-        rebind<const __list_node<_Tp, _VoidPtr> > __node_pointer;
+        rebind<__list_node<_Tp, _VoidPtr> > __node_pointer;
 #else
-        rebind<const __list_node<_Tp, _VoidPtr> >::other __node_pointer;
+        rebind<__list_node<_Tp, _VoidPtr> >::other __node_pointer;
 #endif
 
     __node_pointer __ptr_;
@@ -439,7 +453,14 @@ public:
         return __ptr_->__value_;
     }
     _LIBCPP_INLINE_VISIBILITY
-    pointer operator->() const {return &(operator*());}
+    pointer operator->() const
+    {
+#if _LIBCPP_DEBUG_LEVEL >= 2
+        _LIBCPP_ASSERT(__get_const_db()->__dereferenceable(this),
+                       "Attempted to dereference a non-dereferenceable list::iterator");
+#endif
+        return pointer_traits<pointer>::pointer_to(__ptr_->__value_);
+    }
 
     _LIBCPP_INLINE_VISIBILITY
     __list_const_iterator& operator++()
@@ -505,11 +526,20 @@ protected:
                                                                      __node_allocator;
     typedef allocator_traits<__node_allocator>                       __node_alloc_traits;
     typedef typename __node_alloc_traits::pointer                    __node_pointer;
-    typedef typename __node_alloc_traits::const_pointer              __node_const_pointer;
+    typedef typename __node_alloc_traits::pointer                    __node_const_pointer;
     typedef typename __alloc_traits::pointer                         pointer;
     typedef typename __alloc_traits::const_pointer                   const_pointer;
     typedef typename __alloc_traits::difference_type                 difference_type;
 
+    typedef typename __alloc_traits::template
+#ifndef _LIBCPP_HAS_NO_TEMPLATE_ALIASES
+                rebind_alloc<__node_base>
+#else
+                rebind_alloc<__node_base>::other
+#endif
+                                                                     __node_base_allocator;
+    typedef typename allocator_traits<__node_base_allocator>::pointer __node_base_pointer;
+
     __node_base __end_;
     __compressed_pair<size_type, __node_allocator> __size_alloc_;
 
@@ -525,7 +555,7 @@ protected:
     const __node_allocator& __node_alloc() const _NOEXCEPT
         {return __size_alloc_.second();}
 
-    static void __unlink_nodes(__node_base& __f, __node_base& __l) _NOEXCEPT;
+    static void __unlink_nodes(__node_pointer __f, __node_pointer __l) _NOEXCEPT;
 
     __list_imp()
         _NOEXCEPT_(is_nothrow_default_constructible<__node_allocator>::value);
@@ -557,18 +587,22 @@ protected:
     iterator end() _NOEXCEPT
     {
 #if _LIBCPP_DEBUG_LEVEL >= 2
-        return iterator(static_cast<__node_pointer>(&__end_), this);
+        return iterator(static_cast<__node_pointer>(
+                pointer_traits<__node_base_pointer>::pointer_to(__end_)), this);
 #else
-        return iterator(static_cast<__node_pointer>(&__end_));
+        return iterator(static_cast<__node_pointer>(
+                      pointer_traits<__node_base_pointer>::pointer_to(__end_)));
 #endif
     }
     _LIBCPP_INLINE_VISIBILITY
     const_iterator end() const _NOEXCEPT
     {
 #if _LIBCPP_DEBUG_LEVEL >= 2
-        return const_iterator(static_cast<__node_const_pointer>(&__end_), this);
+        return const_iterator(static_cast<__node_const_pointer>(
+        pointer_traits<__node_base_pointer>::pointer_to(const_cast<__node_base&>(__end_))), this);
 #else
-        return const_iterator(static_cast<__node_const_pointer>(&__end_));
+        return const_iterator(static_cast<__node_const_pointer>(
+        pointer_traits<__node_base_pointer>::pointer_to(const_cast<__node_base&>(__end_))));
 #endif
     }
 
@@ -637,11 +671,11 @@ private:
 template <class _Tp, class _Alloc>
 inline _LIBCPP_INLINE_VISIBILITY
 void
-__list_imp<_Tp, _Alloc>::__unlink_nodes(__node_base& __f, __node_base& __l)
+__list_imp<_Tp, _Alloc>::__unlink_nodes(__node_pointer __f, __node_pointer __l)
     _NOEXCEPT
 {
-    __f.__prev_->__next_ = __l.__next_;
-    __l.__next_->__prev_ = __f.__prev_;
+    __f->__prev_->__next_ = __l->__next_;
+    __l->__next_->__prev_ = __f->__prev_;
 }
 
 template <class _Tp, class _Alloc>
@@ -676,15 +710,16 @@ __list_imp<_Tp, _Alloc>::clear() _NOEXCEPT
     {
         __node_allocator& __na = __node_alloc();
         __node_pointer __f = __end_.__next_;
-        __node_pointer __l = static_cast<__node_pointer>(&__end_);
-        __unlink_nodes(*__f, *__l->__prev_);
+        __node_pointer __l = static_cast<__node_pointer>(
+                       pointer_traits<__node_base_pointer>::pointer_to(__end_));
+        __unlink_nodes(__f, __l->__prev_);
         __sz() = 0;
         while (__f != __l)
         {
-            __node& __n = *__f;
+            __node_pointer __n = __f;
             __f = __f->__next_;
-            __node_alloc_traits::destroy(__na, _VSTD::addressof(__n.__value_));
-            __node_alloc_traits::deallocate(__na, _VSTD::addressof(__n), 1);
+            __node_alloc_traits::destroy(__na, _VSTD::addressof(__n->__value_));
+            __node_alloc_traits::deallocate(__na, __n, 1);
         }
 #if _LIBCPP_DEBUG_LEVEL >= 2
         __c_node* __c = __get_db()->__find_c_and_lock(this);
@@ -719,16 +754,20 @@ __list_imp<_Tp, _Alloc>::swap(__list_imp& __c)
     swap(__sz(), __c.__sz());
     swap(__end_, __c.__end_);
     if (__sz() == 0)
-        __end_.__next_ = __end_.__prev_ = &static_cast<__node&>(__end_);
+        __end_.__next_ = __end_.__prev_ = static_cast<__node_pointer>(
+                       pointer_traits<__node_base_pointer>::pointer_to(__end_));
     else
         __end_.__prev_->__next_ = __end_.__next_->__prev_
-                                = &static_cast<__node&>(__end_);
+                                = static_cast<__node_pointer>(
+                       pointer_traits<__node_base_pointer>::pointer_to(__end_));
     if (__c.__sz() == 0)
         __c.__end_.__next_ = __c.__end_.__prev_
-                           = &static_cast<__node&>(__c.__end_);
+                           = static_cast<__node_pointer>(
+                       pointer_traits<__node_base_pointer>::pointer_to(__c.__end_));
     else
         __c.__end_.__prev_->__next_ = __c.__end_.__next_->__prev_
-                                    = &static_cast<__node&>(__c.__end_);
+                                    = static_cast<__node_pointer>(
+                       pointer_traits<__node_base_pointer>::pointer_to(__c.__end_));
 #if _LIBCPP_DEBUG_LEVEL >= 2
     __libcpp_db* __db = __get_db();
     __c_node* __cn1 = __db->__find_c_and_lock(this);
@@ -740,7 +779,8 @@ __list_imp<_Tp, _Alloc>::swap(__list_imp& __c)
     {
         --__p;
         const_iterator* __i = static_cast<const_iterator*>((*__p)->__i_);
-        if (__i->__ptr_ == static_cast<__node_pointer>(&__c.__end_))
+        if (__i->__ptr_ == static_cast<__node_pointer>(
+                       pointer_traits<__node_base_pointer>::pointer_to(__c.__end_)))
         {
             __cn2->__add(*__p);
             if (--__cn1->end_ != __p)
@@ -753,7 +793,8 @@ __list_imp<_Tp, _Alloc>::swap(__list_imp& __c)
     {
         --__p;
         const_iterator* __i = static_cast<const_iterator*>((*__p)->__i_);
-        if (__i->__ptr_ == static_cast<__node_pointer>(&__end_))
+        if (__i->__ptr_ == static_cast<__node_pointer>(
+                       pointer_traits<__node_base_pointer>::pointer_to(__end_)))
         {
             __cn1->__add(*__p);
             if (--__cn2->end_ != __p)
@@ -775,6 +816,8 @@ class _LIBCPP_TYPE_VIS list
     typedef typename base::__node_allocator    __node_allocator;
     typedef typename base::__node_pointer      __node_pointer;
     typedef typename base::__node_alloc_traits __node_alloc_traits;
+    typedef typename base::__node_base         __node_base;
+    typedef typename base::__node_base_pointer __node_base_pointer;
 
 public:
     typedef _Tp                                      value_type;
@@ -1014,7 +1057,7 @@ public:
 #endif  // _LIBCPP_DEBUG_LEVEL >= 2
 
 private:
-    static void __link_nodes(__node& __p, __node& __f, __node& __l);
+    static void __link_nodes(__node_pointer __p, __node_pointer __f, __node_pointer __l);
     iterator __iterator(size_type __n);
     template <class _Comp>
         static iterator __sort(iterator __f1, iterator __e2, size_type __n, _Comp& __comp);
@@ -1028,12 +1071,12 @@ private:
 template <class _Tp, class _Alloc>
 inline _LIBCPP_INLINE_VISIBILITY
 void
-list<_Tp, _Alloc>::__link_nodes(__node& __p, __node& __f, __node& __l)
+list<_Tp, _Alloc>::__link_nodes(__node_pointer __p, __node_pointer __f, __node_pointer __l)
 {
-    __p.__prev_->__next_ = &__f;
-    __f.__prev_ = __p.__prev_;
-    __p.__prev_ = &__l;
-    __l.__next_ = &__p;
+    __p->__prev_->__next_ = __f;
+    __f->__prev_ = __p->__prev_;
+    __p->__prev_ = __l;
+    __l->__next_ = __p;
 }
 
 template <class _Tp, class _Alloc>
@@ -1290,7 +1333,7 @@ list<_Tp, _Alloc>::insert(const_iterator __p, const value_type& __x)
     unique_ptr<__node, _Dp> __hold(__node_alloc_traits::allocate(__na, 1), _Dp(__na, 1));
     __hold->__prev_ = 0;
     __node_alloc_traits::construct(__na, _VSTD::addressof(__hold->__value_), __x);
-    __link_nodes(const_cast<__node&>(*__p.__ptr_), *__hold, *__hold);
+    __link_nodes(__p.__ptr_, __hold.get(), __hold.get());
     ++base::__sz();
 #if _LIBCPP_DEBUG_LEVEL >= 2
     return iterator(__hold.release(), this);
@@ -1307,9 +1350,9 @@ list<_Tp, _Alloc>::insert(const_iterator __p, size_type __n, const value_type& _
     _LIBCPP_ASSERT(__get_const_db()->__find_c_from_i(&__p) == this,
         "list::insert(iterator, n, x) called with an iterator not"
         " referring to this list");
-    iterator __r(const_cast<__node_pointer>(__p.__ptr_), this);
+    iterator __r(__p.__ptr_, this);
 #else
-    iterator __r(const_cast<__node_pointer>(__p.__ptr_));
+    iterator __r(__p.__ptr_);
 #endif
     if (__n > 0)
     {
@@ -1359,7 +1402,7 @@ list<_Tp, _Alloc>::insert(const_iterator __p, size_type __n, const value_type& _
             throw;
         }
 #endif  // _LIBCPP_NO_EXCEPTIONS
-        __link_nodes(const_cast<__node&>(*__p.__ptr_), *__r.__ptr_, *__e.__ptr_);
+        __link_nodes(__p.__ptr_, __r.__ptr_, __e.__ptr_);
         base::__sz() += __ds;
     }
     return __r;
@@ -1375,9 +1418,9 @@ list<_Tp, _Alloc>::insert(const_iterator __p, _InpIter __f, _InpIter __l,
     _LIBCPP_ASSERT(__get_const_db()->__find_c_from_i(&__p) == this,
         "list::insert(iterator, range) called with an iterator not"
         " referring to this list");
-    iterator __r(const_cast<__node_pointer>(__p.__ptr_), this);
+    iterator __r(__p.__ptr_, this);
 #else
-    iterator __r(const_cast<__node_pointer>(__p.__ptr_));
+    iterator __r(__p.__ptr_);
 #endif
     if (__f != __l)
     {
@@ -1427,7 +1470,7 @@ list<_Tp, _Alloc>::insert(const_iterator __p, _InpIter __f, _InpIter __l,
             throw;
         }
 #endif  // _LIBCPP_NO_EXCEPTIONS
-        __link_nodes(const_cast<__node&>(*__p.__ptr_), *__r.__ptr_, *__e.__ptr_);
+        __link_nodes(__p.__ptr_, __r.__ptr_, __e.__ptr_);
         base::__sz() += __ds;
     }
     return __r;
@@ -1441,7 +1484,7 @@ list<_Tp, _Alloc>::push_front(const value_type& __x)
     typedef __allocator_destructor<__node_allocator> _Dp;
     unique_ptr<__node, _Dp> __hold(__node_alloc_traits::allocate(__na, 1), _Dp(__na, 1));
     __node_alloc_traits::construct(__na, _VSTD::addressof(__hold->__value_), __x);
-    __link_nodes(*base::__end_.__next_, *__hold, *__hold);
+    __link_nodes(base::__end_.__next_, __hold.get(), __hold.get());
     ++base::__sz();
     __hold.release();
 }
@@ -1454,7 +1497,8 @@ list<_Tp, _Alloc>::push_back(const value_type& __x)
     typedef __allocator_destructor<__node_allocator> _Dp;
     unique_ptr<__node, _Dp> __hold(__node_alloc_traits::allocate(__na, 1), _Dp(__na, 1));
     __node_alloc_traits::construct(__na, _VSTD::addressof(__hold->__value_), __x);
-    __link_nodes(static_cast<__node&>(base::__end_), *__hold, *__hold);
+    __link_nodes(static_cast<__node_pointer>(pointer_traits<__node_base_pointer>::
+                         pointer_to(base::__end_)), __hold.get(), __hold.get());
     ++base::__sz();
     __hold.release();
 }
@@ -1469,7 +1513,7 @@ list<_Tp, _Alloc>::push_front(value_type&& __x)
     typedef __allocator_destructor<__node_allocator> _Dp;
     unique_ptr<__node, _Dp> __hold(__node_alloc_traits::allocate(__na, 1), _Dp(__na, 1));
     __node_alloc_traits::construct(__na, _VSTD::addressof(__hold->__value_), _VSTD::move(__x));
-    __link_nodes(*base::__end_.__next_, *__hold, *__hold);
+    __link_nodes(base::__end_.__next_, __hold.get(), __hold.get());
     ++base::__sz();
     __hold.release();
 }
@@ -1482,7 +1526,8 @@ list<_Tp, _Alloc>::push_back(value_type&& __x)
     typedef __allocator_destructor<__node_allocator> _Dp;
     unique_ptr<__node, _Dp> __hold(__node_alloc_traits::allocate(__na, 1), _Dp(__na, 1));
     __node_alloc_traits::construct(__na, _VSTD::addressof(__hold->__value_), _VSTD::move(__x));
-    __link_nodes(static_cast<__node&>(base::__end_), *__hold, *__hold);
+    __link_nodes(static_cast<__node_pointer>(pointer_traits<__node_base_pointer>::
+                         pointer_to(base::__end_)), __hold.get(), __hold.get());
     ++base::__sz();
     __hold.release();
 }
@@ -1498,7 +1543,7 @@ list<_Tp, _Alloc>::emplace_front(_Args&&... __args)
     typedef __allocator_destructor<__node_allocator> _Dp;
     unique_ptr<__node, _Dp> __hold(__node_alloc_traits::allocate(__na, 1), _Dp(__na, 1));
     __node_alloc_traits::construct(__na, _VSTD::addressof(__hold->__value_), _VSTD::forward<_Args>(__args)...);
-    __link_nodes(*base::__end_.__next_, *__hold, *__hold);
+    __link_nodes(base::__end_.__next_, __hold.get(), __hold.get());
     ++base::__sz();
     __hold.release();
 }
@@ -1512,7 +1557,8 @@ list<_Tp, _Alloc>::emplace_back(_Args&&... __args)
     typedef __allocator_destructor<__node_allocator> _Dp;
     unique_ptr<__node, _Dp> __hold(__node_alloc_traits::allocate(__na, 1), _Dp(__na, 1));
     __node_alloc_traits::construct(__na, _VSTD::addressof(__hold->__value_), _VSTD::forward<_Args>(__args)...);
-    __link_nodes(static_cast<__node&>(base::__end_), *__hold, *__hold);
+    __link_nodes(static_cast<__node_pointer>(pointer_traits<__node_base_pointer>::
+                         pointer_to(base::__end_)), __hold.get(), __hold.get());
     ++base::__sz();
     __hold.release();
 }
@@ -1532,7 +1578,7 @@ list<_Tp, _Alloc>::emplace(const_iterator __p, _Args&&... __args)
     unique_ptr<__node, _Dp> __hold(__node_alloc_traits::allocate(__na, 1), _Dp(__na, 1));
     __hold->__prev_ = 0;
     __node_alloc_traits::construct(__na, _VSTD::addressof(__hold->__value_), _VSTD::forward<_Args>(__args)...);
-    __link_nodes(const_cast<__node&>(*__p.__ptr_), *__hold, *__hold);
+    __link_nodes(__p.__ptr_, __hold.get(), __hold.get());
     ++base::__sz();
 #if _LIBCPP_DEBUG_LEVEL >= 2
     return iterator(__hold.release(), this);
@@ -1557,7 +1603,7 @@ list<_Tp, _Alloc>::insert(const_iterator __p, value_type&& __x)
     unique_ptr<__node, _Dp> __hold(__node_alloc_traits::allocate(__na, 1), _Dp(__na, 1));
     __hold->__prev_ = 0;
     __node_alloc_traits::construct(__na, _VSTD::addressof(__hold->__value_), _VSTD::move(__x));
-    __link_nodes(const_cast<__node&>(*__p.__ptr_), *__hold, *__hold);
+    __link_nodes(__p.__ptr_, __hold.get(), __hold.get());
     ++base::__sz();
 #if _LIBCPP_DEBUG_LEVEL >= 2
     return iterator(__hold.release(), this);
@@ -1574,7 +1620,7 @@ list<_Tp, _Alloc>::pop_front()
 {
     _LIBCPP_ASSERT(!empty(), "list::pop_front() called with empty list");
     __node_allocator& __na = base::__node_alloc();
-    __node& __n = *base::__end_.__next_;
+    __node_pointer __n = base::__end_.__next_;
     base::__unlink_nodes(__n, __n);
     --base::__sz();
 #if _LIBCPP_DEBUG_LEVEL >= 2
@@ -1583,7 +1629,7 @@ list<_Tp, _Alloc>::pop_front()
     {
         --__p;
         iterator* __i = static_cast<iterator*>((*__p)->__i_);
-        if (__i->__ptr_ == &__n)
+        if (__i->__ptr_ == __n)
         {
             (*__p)->__c_ = nullptr;
             if (--__c->end_ != __p)
@@ -1592,17 +1638,17 @@ list<_Tp, _Alloc>::pop_front()
     }
     __get_db()->unlock();
 #endif
-    __node_alloc_traits::destroy(__na, _VSTD::addressof(__n.__value_));
-    __node_alloc_traits::deallocate(__na, _VSTD::addressof(__n), 1);
+    __node_alloc_traits::destroy(__na, _VSTD::addressof(__n->__value_));
+    __node_alloc_traits::deallocate(__na, __n, 1);
 }
 
 template <class _Tp, class _Alloc>
 void
 list<_Tp, _Alloc>::pop_back()
 {
-    _LIBCPP_ASSERT(!empty(), "list::pop_front() called with empty list");
+    _LIBCPP_ASSERT(!empty(), "list::pop_back() called with empty list");
     __node_allocator& __na = base::__node_alloc();
-    __node& __n = *base::__end_.__prev_;
+    __node_pointer __n = base::__end_.__prev_;
     base::__unlink_nodes(__n, __n);
     --base::__sz();
 #if _LIBCPP_DEBUG_LEVEL >= 2
@@ -1611,7 +1657,7 @@ list<_Tp, _Alloc>::pop_back()
     {
         --__p;
         iterator* __i = static_cast<iterator*>((*__p)->__i_);
-        if (__i->__ptr_ == &__n)
+        if (__i->__ptr_ == __n)
         {
             (*__p)->__c_ = nullptr;
             if (--__c->end_ != __p)
@@ -1620,8 +1666,8 @@ list<_Tp, _Alloc>::pop_back()
     }
     __get_db()->unlock();
 #endif
-    __node_alloc_traits::destroy(__na, _VSTD::addressof(__n.__value_));
-    __node_alloc_traits::deallocate(__na, _VSTD::addressof(__n), 1);
+    __node_alloc_traits::destroy(__na, _VSTD::addressof(__n->__value_));
+    __node_alloc_traits::deallocate(__na, __n, 1);
 }
 
 template <class _Tp, class _Alloc>
@@ -1636,8 +1682,8 @@ list<_Tp, _Alloc>::erase(const_iterator __p)
     _LIBCPP_ASSERT(__p != end(),
         "list::erase(iterator) called with a non-dereferenceable iterator");
     __node_allocator& __na = base::__node_alloc();
-    __node& __n = const_cast<__node&>(*__p.__ptr_);
-    __node_pointer __r = __n.__next_;
+    __node_pointer __n = __p.__ptr_;
+    __node_pointer __r = __n->__next_;
     base::__unlink_nodes(__n, __n);
     --base::__sz();
 #if _LIBCPP_DEBUG_LEVEL >= 2
@@ -1646,7 +1692,7 @@ list<_Tp, _Alloc>::erase(const_iterator __p)
     {
         --__p;
         iterator* __i = static_cast<iterator*>((*__p)->__i_);
-        if (__i->__ptr_ == &__n)
+        if (__i->__ptr_ == __n)
         {
             (*__p)->__c_ = nullptr;
             if (--__c->end_ != __p)
@@ -1655,8 +1701,8 @@ list<_Tp, _Alloc>::erase(const_iterator __p)
     }
     __get_db()->unlock();
 #endif
-    __node_alloc_traits::destroy(__na, _VSTD::addressof(__n.__value_));
-    __node_alloc_traits::deallocate(__na, _VSTD::addressof(__n), 1);
+    __node_alloc_traits::destroy(__na, _VSTD::addressof(__n->__value_));
+    __node_alloc_traits::deallocate(__na, __n, 1);
 #if _LIBCPP_DEBUG_LEVEL >= 2
     return iterator(__r, this);
 #else
@@ -1676,10 +1722,10 @@ list<_Tp, _Alloc>::erase(const_iterator __f, const_iterator __l)
     if (__f != __l)
     {
         __node_allocator& __na = base::__node_alloc();
-        base::__unlink_nodes(const_cast<__node&>(*__f.__ptr_), *__l.__ptr_->__prev_);
+        base::__unlink_nodes(__f.__ptr_, __l.__ptr_->__prev_);
         while (__f != __l)
         {
-            __node& __n = const_cast<__node&>(*__f.__ptr_);
+            __node_pointer __n = __f.__ptr_;
             ++__f;
             --base::__sz();
 #if _LIBCPP_DEBUG_LEVEL >= 2
@@ -1688,7 +1734,7 @@ list<_Tp, _Alloc>::erase(const_iterator __f, const_iterator __l)
             {
                 --__p;
                 iterator* __i = static_cast<iterator*>((*__p)->__i_);
-                if (__i->__ptr_ == &__n)
+                if (__i->__ptr_ == __n)
                 {
                     (*__p)->__c_ = nullptr;
                     if (--__c->end_ != __p)
@@ -1697,14 +1743,14 @@ list<_Tp, _Alloc>::erase(const_iterator __f, const_iterator __l)
             }
             __get_db()->unlock();
 #endif
-            __node_alloc_traits::destroy(__na, _VSTD::addressof(__n.__value_));
-            __node_alloc_traits::deallocate(__na, _VSTD::addressof(__n), 1);
+            __node_alloc_traits::destroy(__na, _VSTD::addressof(__n->__value_));
+            __node_alloc_traits::deallocate(__na, __n, 1);
         }
     }
 #if _LIBCPP_DEBUG_LEVEL >= 2
-    return iterator(const_cast<__node_pointer>(__l.__ptr_), this);
+    return iterator(__l.__ptr_, this);
 #else
-    return iterator(const_cast<__node_pointer>(__l.__ptr_));
+    return iterator(__l.__ptr_);
 #endif
 }
 
@@ -1762,7 +1808,8 @@ list<_Tp, _Alloc>::resize(size_type __n)
             throw;
         }
 #endif  // _LIBCPP_NO_EXCEPTIONS
-        __link_nodes(static_cast<__node&>(base::__end_), *__r.__ptr_, *__e.__ptr_);
+        __link_nodes(static_cast<__node_pointer>(pointer_traits<__node_base_pointer>::
+                         pointer_to(base::__end_)), __r.__ptr_, __e.__ptr_);
         base::__sz() += __ds;
     }
 }
@@ -1821,7 +1868,8 @@ list<_Tp, _Alloc>::resize(size_type __n, const value_type& __x)
             throw;
         }
 #endif  // _LIBCPP_NO_EXCEPTIONS
-        __link_nodes(static_cast<__node&>(base::__end_), *__r.__ptr_, *__e.__ptr_);
+        __link_nodes(static_cast<__node_pointer>(pointer_traits<__node_base_pointer>::
+                         pointer_to(base::__end_)), __r.__ptr_, __e.__ptr_);
         base::__sz() += __ds;
     }
 }
@@ -1839,10 +1887,10 @@ list<_Tp, _Alloc>::splice(const_iterator __p, list& __c)
 #endif
     if (!__c.empty())
     {
-        __node& __f = *__c.__end_.__next_;
-        __node& __l = *__c.__end_.__prev_;
+        __node_pointer __f = __c.__end_.__next_;
+        __node_pointer __l = __c.__end_.__prev_;
         base::__unlink_nodes(__f, __l);
-        __link_nodes(const_cast<__node&>(*__p.__ptr_), __f, __l);
+        __link_nodes(__p.__ptr_, __f, __l);
         base::__sz() += __c.__sz();
         __c.__sz() = 0;
 #if _LIBCPP_DEBUG_LEVEL >= 2
@@ -1853,7 +1901,8 @@ list<_Tp, _Alloc>::splice(const_iterator __p, list& __c)
         {
             --__p;
             iterator* __i = static_cast<iterator*>((*__p)->__i_);
-            if (__i->__ptr_ != static_cast<__node_pointer>(&__c.__end_))
+            if (__i->__ptr_ != static_cast<__node_pointer>(
+                       pointer_traits<__node_base_pointer>::pointer_to(__c.__end_)))
             {
                 __cn1->__add(*__p);
                 (*__p)->__c_ = __cn1;
@@ -1883,9 +1932,9 @@ list<_Tp, _Alloc>::splice(const_iterator __p, list& __c, const_iterator __i)
 #endif
     if (__p.__ptr_ != __i.__ptr_ && __p.__ptr_ != __i.__ptr_->__next_)
     {
-        __node& __f = const_cast<__node&>(*__i.__ptr_);
+        __node_pointer __f = __i.__ptr_;
         base::__unlink_nodes(__f, __f);
-        __link_nodes(const_cast<__node&>(*__p.__ptr_), __f, __f);
+        __link_nodes(__p.__ptr_, __f, __f);
         --__c.__sz();
         ++base::__sz();
 #if _LIBCPP_DEBUG_LEVEL >= 2
@@ -1896,7 +1945,7 @@ list<_Tp, _Alloc>::splice(const_iterator __p, list& __c, const_iterator __i)
         {
             --__p;
             iterator* __j = static_cast<iterator*>((*__p)->__i_);
-            if (__j->__ptr_ == &__f)
+            if (__j->__ptr_ == __f)
             {
                 __cn1->__add(*__p);
                 (*__p)->__c_ = __cn1;
@@ -1937,11 +1986,11 @@ list<_Tp, _Alloc>::splice(const_iterator __p, list& __c, const_iterator __f, con
             __c.__sz() -= __s;
             base::__sz() += __s;
         }
-        __node& __first = const_cast<__node&>(*__f.__ptr_);
+        __node_pointer __first = __f.__ptr_;
         --__l;
-        __node& __last = const_cast<__node&>(*__l.__ptr_);
+        __node_pointer __last = __l.__ptr_;
         base::__unlink_nodes(__first, __last);
-        __link_nodes(const_cast<__node&>(*__p.__ptr_), __first, __last);
+        __link_nodes(__p.__ptr_, __first, __last);
 #if _LIBCPP_DEBUG_LEVEL >= 2
         __libcpp_db* __db = __get_db();
         __c_node* __cn1 = __db->__find_c_and_lock(this);
@@ -1950,7 +1999,7 @@ list<_Tp, _Alloc>::splice(const_iterator __p, list& __c, const_iterator __f, con
         {
             --__p;
             iterator* __j = static_cast<iterator*>((*__p)->__i_);
-            for (__node_pointer __k = const_cast<__node_pointer>(__f.__ptr_);
+            for (__node_pointer __k = __f.__ptr_;
                                           __k != __l.__ptr_; __k = __k->__next_)
             {
                 if (__j->__ptr_ == __k)
@@ -2056,12 +2105,12 @@ list<_Tp, _Alloc>::merge(list& __c, _Comp __comp)
                     ;
                 base::__sz() += __ds;
                 __c.__sz() -= __ds;
-                __node& __f = *__f2.__ptr_;
-                __node& __l = *__m2.__ptr_->__prev_;
+                __node_pointer __f = __f2.__ptr_;
+                __node_pointer __l = __m2.__ptr_->__prev_;
                 __f2 = __m2;
                 base::__unlink_nodes(__f, __l);
                 __m2 = _VSTD::next(__f1);
-                __link_nodes(*__f1.__ptr_, __f, __l);
+                __link_nodes(__f1.__ptr_, __f, __l);
                 __f1 = __m2;
             }
             else
@@ -2076,7 +2125,8 @@ list<_Tp, _Alloc>::merge(list& __c, _Comp __comp)
         {
             --__p;
             iterator* __i = static_cast<iterator*>((*__p)->__i_);
-            if (__i->__ptr_ != static_cast<__node_pointer>(&__c.__end_))
+            if (__i->__ptr_ != static_cast<__node_pointer>(
+                       pointer_traits<__node_base_pointer>::pointer_to(__c.__end_)))
             {
                 __cn1->__add(*__p);
                 (*__p)->__c_ = __cn1;
@@ -2119,9 +2169,9 @@ list<_Tp, _Alloc>::__sort(iterator __f1, iterator __e2, size_type __n, _Comp& __
     case 2:
         if (__comp(*--__e2, *__f1))
         {
-            __node& __f = *__e2.__ptr_;
+            __node_pointer __f = __e2.__ptr_;
             base::__unlink_nodes(__f, __f);
-            __link_nodes(*__f1.__ptr_, __f, __f);
+            __link_nodes(__f1.__ptr_, __f, __f);
             return __e2;
         }
         return __f1;
@@ -2135,13 +2185,13 @@ list<_Tp, _Alloc>::__sort(iterator __f1, iterator __e2, size_type __n, _Comp& __
         iterator __m2 = _VSTD::next(__f2);
         for (; __m2 != __e2 && __comp(*__m2, *__f1); ++__m2)
             ;
-        __node& __f = *__f2.__ptr_;
-        __node& __l = *__m2.__ptr_->__prev_;
+        __node_pointer __f = __f2.__ptr_;
+        __node_pointer __l = __m2.__ptr_->__prev_;
         __r = __f2;
         __e1 = __f2 = __m2;
         base::__unlink_nodes(__f, __l);
         __m2 = _VSTD::next(__f1);
-        __link_nodes(*__f1.__ptr_, __f, __l);
+        __link_nodes(__f1.__ptr_, __f, __l);
         __f1 = __m2;
     }
     else
@@ -2153,14 +2203,14 @@ list<_Tp, _Alloc>::__sort(iterator __f1, iterator __e2, size_type __n, _Comp& __
             iterator __m2 = _VSTD::next(__f2);
             for (; __m2 != __e2 && __comp(*__m2, *__f1); ++__m2)
                 ;
-            __node& __f = *__f2.__ptr_;
-            __node& __l = *__m2.__ptr_->__prev_;
+            __node_pointer __f = __f2.__ptr_;
+            __node_pointer __l = __m2.__ptr_->__prev_;
             if (__e1 == __f2)
                 __e1 = __m2;
             __f2 = __m2;
             base::__unlink_nodes(__f, __l);
             __m2 = _VSTD::next(__f1);
-            __link_nodes(*__f1.__ptr_, __f, __l);
+            __link_nodes(__f1.__ptr_, __f, __l);
             __f1 = __m2;
         }
         else
@@ -2198,7 +2248,8 @@ template <class _Tp, class _Alloc>
 bool
 list<_Tp, _Alloc>::__dereferenceable(const const_iterator* __i) const
 {
-    return __i->__ptr_ != &this->__end_;
+    return __i->__ptr_ != static_cast<__node_pointer>(
+                       pointer_traits<__node_base_pointer>::pointer_to(const_cast<__node_base&>(this->__end_)));
 }
 
 template <class _Tp, class _Alloc>
diff --git a/include/locale b/include/locale
index 49f9c08fa8cc..ef7603d036cf 100644
--- a/include/locale
+++ b/include/locale
@@ -206,6 +206,8 @@ _LIBCPP_BEGIN_NAMESPACE_STD
 
 #if defined(__APPLE__) || defined(__FreeBSD__)
 #  define _LIBCPP_GET_C_LOCALE 0
+#elif defined(__NetBSD__)
+#  define _LIBCPP_GET_C_LOCALE LC_C_LOCALE
 #else
 #  define _LIBCPP_GET_C_LOCALE __cloc()
    // Get the C locale object
@@ -355,20 +357,6 @@ size_t __mbsrtowcs_l(wchar_t *__dest, const char **__src, size_t __len,
 }
 
 inline
-int __sprintf_l(char *__s, locale_t __l, const char *__format, ...) {
-  va_list __va;
-  va_start(__va, __format);
-#ifdef _LIBCPP_LOCALE__L_EXTENSIONS
-  int __res = vsprintf_l(__s, __l, __format, __va);
-#else
-  __locale_raii __current(uselocale(__l), uselocale);
-  int __res = vsprintf(__s, __format, __va);
-#endif
-  va_end(__va);
-  return __res;
-}
-
-inline
 int __snprintf_l(char *__s, size_t __n, locale_t __l, const char *__format, ...) {
   va_list __va;
   va_start(__va, __format);
@@ -1801,9 +1789,9 @@ num_put<_CharT, _OutputIterator>::do_put(iter_type __s, ios_base& __iob,
                           + 1;
     char __nar[__nbuf];
 #ifdef _LIBCPP_LOCALE__L_EXTENSIONS
-    int __nc = sprintf_l(__nar, _LIBCPP_GET_C_LOCALE, __fmt, __v);
+    int __nc = snprintf_l(__nar, sizeof(__nar), _LIBCPP_GET_C_LOCALE, __fmt, __v);
 #else
-    int __nc = __sprintf_l(__nar, __cloc(), __fmt, __v);
+    int __nc = __snprintf_l(__nar, sizeof(__nar), __cloc(), __fmt, __v);
 #endif
     char* __ne = __nar + __nc;
     char* __np = this->__identify_padding(__nar, __ne, __iob);
@@ -1831,9 +1819,9 @@ num_put<_CharT, _OutputIterator>::do_put(iter_type __s, ios_base& __iob,
                           + 1;
     char __nar[__nbuf];
 #ifdef _LIBCPP_LOCALE__L_EXTENSIONS
-    int __nc = sprintf_l(__nar, _LIBCPP_GET_C_LOCALE, __fmt, __v);
+    int __nc = snprintf_l(__nar, sizeof(__nar), _LIBCPP_GET_C_LOCALE, __fmt, __v);
 #else
-    int __nc = __sprintf_l(__nar, __cloc(), __fmt, __v);
+    int __nc = __snprintf_l(__nar, sizeof(__nar), __cloc(), __fmt, __v);
 #endif
     char* __ne = __nar + __nc;
     char* __np = this->__identify_padding(__nar, __ne, __iob);
@@ -1861,9 +1849,9 @@ num_put<_CharT, _OutputIterator>::do_put(iter_type __s, ios_base& __iob,
                           + 1;
     char __nar[__nbuf];
 #ifdef _LIBCPP_LOCALE__L_EXTENSIONS
-    int __nc = sprintf_l(__nar, _LIBCPP_GET_C_LOCALE, __fmt, __v);
+    int __nc = snprintf_l(__nar, sizeof(__nar), _LIBCPP_GET_C_LOCALE, __fmt, __v);
 #else
-    int __nc = __sprintf_l(__nar, __cloc(), __fmt, __v);
+    int __nc = __snprintf_l(__nar, sizeof(__nar), __cloc(), __fmt, __v);
 #endif
     char* __ne = __nar + __nc;
     char* __np = this->__identify_padding(__nar, __ne, __iob);
@@ -1891,9 +1879,9 @@ num_put<_CharT, _OutputIterator>::do_put(iter_type __s, ios_base& __iob,
                           + 1;
     char __nar[__nbuf];
 #ifdef _LIBCPP_LOCALE__L_EXTENSIONS
-    int __nc = sprintf_l(__nar, _LIBCPP_GET_C_LOCALE, __fmt, __v);
+    int __nc = snprintf_l(__nar, sizeof(__nar), _LIBCPP_GET_C_LOCALE, __fmt, __v);
 #else
-    int __nc = __sprintf_l(__nar, __cloc(), __fmt, __v);
+    int __nc = __snprintf_l(__nar, sizeof(__nar), __cloc(), __fmt, __v);
 #endif
     char* __ne = __nar + __nc;
     char* __np = this->__identify_padding(__nar, __ne, __iob);
@@ -2055,9 +2043,9 @@ num_put<_CharT, _OutputIterator>::do_put(iter_type __s, ios_base& __iob,
     const unsigned __nbuf = 20;
     char __nar[__nbuf];
 #ifdef _LIBCPP_LOCALE__L_EXTENSIONS
-    int __nc = sprintf_l(__nar, _LIBCPP_GET_C_LOCALE, __fmt, __v);
+    int __nc = snprintf_l(__nar, sizeof(__nar), _LIBCPP_GET_C_LOCALE, __fmt, __v);
 #else
-    int __nc = __sprintf_l(__nar, __cloc(), __fmt, __v);
+    int __nc = __snprintf_l(__nar, sizeof(__nar), __cloc(), __fmt, __v);
 #endif
     char* __ne = __nar + __nc;
     char* __np = this->__identify_padding(__nar, __ne, __iob);
diff --git a/include/map b/include/map
index abc07a35d0ea..953743a6c740 100644
--- a/include/map
+++ b/include/map
@@ -381,7 +381,7 @@ swap(multimap<Key, T, Compare, Allocator>& x,
 
 _LIBCPP_BEGIN_NAMESPACE_STD
 
-template <class _Key, class _Tp, class _Compare, bool = is_empty<_Compare>::value
+template <class _Key, class _CP, class _Compare, bool = is_empty<_Compare>::value
 #if __has_feature(is_final)
                                                         && !__is_final(_Compare)
 #endif
@@ -389,8 +389,6 @@ template <class _Key, class _Tp, class _Compare, bool = is_empty<_Compare>::valu
 class __map_value_compare
     : private _Compare
 {
-    typedef pair<typename std::remove_const<_Key>::type, _Tp> _Pp;
-    typedef pair<const _Key, _Tp> _CP;
 public:
     _LIBCPP_INLINE_VISIBILITY
     __map_value_compare()
@@ -404,41 +402,20 @@ public:
     const _Compare& key_comp() const _NOEXCEPT {return *this;}
     _LIBCPP_INLINE_VISIBILITY
     bool operator()(const _CP& __x, const _CP& __y) const
-        {return static_cast<const _Compare&>(*this)(__x.first, __y.first);}
-    _LIBCPP_INLINE_VISIBILITY
-    bool operator()(const _CP& __x, const _Pp& __y) const
-        {return static_cast<const _Compare&>(*this)(__x.first, __y.first);}
+        {return static_cast<const _Compare&>(*this)(__x.__cc.first, __y.__cc.first);}
     _LIBCPP_INLINE_VISIBILITY
     bool operator()(const _CP& __x, const _Key& __y) const
-        {return static_cast<const _Compare&>(*this)(__x.first, __y);}
-    _LIBCPP_INLINE_VISIBILITY
-    bool operator()(const _Pp& __x, const _CP& __y) const
-        {return static_cast<const _Compare&>(*this)(__x.first, __y.first);}
-    _LIBCPP_INLINE_VISIBILITY
-    bool operator()(const _Pp& __x, const _Pp& __y) const
-        {return static_cast<const _Compare&>(*this)(__x.first, __y.first);}
-    _LIBCPP_INLINE_VISIBILITY
-    bool operator()(const _Pp& __x, const _Key& __y) const
-        {return static_cast<const _Compare&>(*this)(__x.first, __y);}
+        {return static_cast<const _Compare&>(*this)(__x.__cc.first, __y);}
     _LIBCPP_INLINE_VISIBILITY
     bool operator()(const _Key& __x, const _CP& __y) const
-        {return static_cast<const _Compare&>(*this)(__x, __y.first);}
-    _LIBCPP_INLINE_VISIBILITY
-    bool operator()(const _Key& __x, const _Pp& __y) const
-        {return static_cast<const _Compare&>(*this)(__x, __y.first);}
-    _LIBCPP_INLINE_VISIBILITY
-    bool operator()(const _Key& __x, const _Key& __y) const
-        {return static_cast<const _Compare&>(*this)(__x, __y);}
+        {return static_cast<const _Compare&>(*this)(__x, __y.__cc.first);}
 };
 
-template <class _Key, class _Tp, class _Compare>
-class __map_value_compare<_Key, _Tp, _Compare, false>
+template <class _Key, class _CP, class _Compare>
+class __map_value_compare<_Key, _CP, _Compare, false>
 {
     _Compare comp;
 
-    typedef pair<typename std::remove_const<_Key>::type, _Tp> _Pp;
-    typedef pair<const _Key, _Tp> _CP;
-
 public:
     _LIBCPP_INLINE_VISIBILITY
     __map_value_compare()
@@ -453,31 +430,13 @@ public:
 
     _LIBCPP_INLINE_VISIBILITY
     bool operator()(const _CP& __x, const _CP& __y) const
-        {return comp(__x.first, __y.first);}
-    _LIBCPP_INLINE_VISIBILITY
-    bool operator()(const _CP& __x, const _Pp& __y) const
-        {return comp(__x.first, __y.first);}
+        {return comp(__x.__cc.first, __y.__cc.first);}
     _LIBCPP_INLINE_VISIBILITY
     bool operator()(const _CP& __x, const _Key& __y) const
-        {return comp(__x.first, __y);}
-    _LIBCPP_INLINE_VISIBILITY
-    bool operator()(const _Pp& __x, const _CP& __y) const
-        {return comp(__x.first, __y.first);}
-    _LIBCPP_INLINE_VISIBILITY
-    bool operator()(const _Pp& __x, const _Pp& __y) const
-        {return comp(__x.first, __y.first);}
-    _LIBCPP_INLINE_VISIBILITY
-    bool operator()(const _Pp& __x, const _Key& __y) const
-        {return comp(__x.first, __y);}
+        {return comp(__x.__cc.first, __y);}
     _LIBCPP_INLINE_VISIBILITY
     bool operator()(const _Key& __x, const _CP& __y) const
-        {return comp(__x, __y.first);}
-    _LIBCPP_INLINE_VISIBILITY
-    bool operator()(const _Key& __x, const _Pp& __y) const
-        {return comp(__x, __y.first);}
-    _LIBCPP_INLINE_VISIBILITY
-    bool operator()(const _Key& __x, const _Key& __y) const
-        {return comp(__x, __y);}
+        {return comp(__x, __y.__cc.first);}
 };
 
 template <class _Allocator>
@@ -489,8 +448,8 @@ class __map_node_destructor
 public:
     typedef typename __alloc_traits::pointer    pointer;
 private:
-    typedef typename value_type::first_type     first_type;
-    typedef typename value_type::second_type    second_type;
+    typedef typename value_type::value_type::first_type     first_type;
+    typedef typename value_type::value_type::second_type    second_type;
 
     allocator_type& __na_;
 
@@ -522,9 +481,9 @@ public:
     void operator()(pointer __p) _NOEXCEPT
     {
         if (__second_constructed)
-            __alloc_traits::destroy(__na_, _VSTD::addressof(__p->__value_.second));
+            __alloc_traits::destroy(__na_, _VSTD::addressof(__p->__value_.__cc.second));
         if (__first_constructed)
-            __alloc_traits::destroy(__na_, _VSTD::addressof(__p->__value_.first));
+            __alloc_traits::destroy(__na_, _VSTD::addressof(__p->__value_.__cc.first));
         if (__p)
             __alloc_traits::deallocate(__na_, __p, 1);
     }
@@ -542,8 +501,8 @@ class _LIBCPP_TYPE_VIS __map_iterator
     _TreeIterator __i_;
 
     typedef typename _TreeIterator::__pointer_traits             __pointer_traits;
-    typedef const typename _TreeIterator::value_type::first_type __key_type;
-    typedef typename _TreeIterator::value_type::second_type      __mapped_type;
+    typedef const typename _TreeIterator::value_type::value_type::first_type __key_type;
+    typedef typename _TreeIterator::value_type::value_type::second_type      __mapped_type;
 public:
     typedef bidirectional_iterator_tag                           iterator_category;
     typedef pair<__key_type, __mapped_type>                      value_type;
@@ -564,9 +523,9 @@ public:
     __map_iterator(_TreeIterator __i) _NOEXCEPT : __i_(__i) {}
 
     _LIBCPP_INLINE_VISIBILITY
-    reference operator*() const {return *operator->();}
+    reference operator*() const {return __i_->__cc;}
     _LIBCPP_INLINE_VISIBILITY
-    pointer operator->() const {return (pointer)__i_.operator->();}
+    pointer operator->() const {return pointer_traits<pointer>::pointer_to(__i_->__cc);}
 
     _LIBCPP_INLINE_VISIBILITY
     __map_iterator& operator++() {++__i_; return *this;}
@@ -607,8 +566,8 @@ class _LIBCPP_TYPE_VIS __map_const_iterator
     _TreeIterator __i_;
 
     typedef typename _TreeIterator::__pointer_traits             __pointer_traits;
-    typedef const typename _TreeIterator::value_type::first_type __key_type;
-    typedef typename _TreeIterator::value_type::second_type      __mapped_type;
+    typedef const typename _TreeIterator::value_type::value_type::first_type __key_type;
+    typedef typename _TreeIterator::value_type::value_type::second_type      __mapped_type;
 public:
     typedef bidirectional_iterator_tag                           iterator_category;
     typedef pair<__key_type, __mapped_type>                      value_type;
@@ -634,9 +593,9 @@ public:
                 : __i_(__i.__i_) {}
 
     _LIBCPP_INLINE_VISIBILITY
-    reference operator*() const {return *operator->();}
+    reference operator*() const {return __i_->__cc;}
     _LIBCPP_INLINE_VISIBILITY
-    pointer operator->() const {return (pointer)__i_.operator->();}
+    pointer operator->() const {return pointer_traits<pointer>::pointer_to(__i_->__cc);}
 
     _LIBCPP_INLINE_VISIBILITY
     __map_const_iterator& operator++() {++__i_; return *this;}
@@ -679,6 +638,7 @@ public:
     typedef _Key                                     key_type;
     typedef _Tp                                      mapped_type;
     typedef pair<const key_type, mapped_type>        value_type;
+    typedef pair<key_type, mapped_type>              __nc_value_type;
     typedef _Compare                                 key_compare;
     typedef _Allocator                               allocator_type;
     typedef value_type&                              reference;
@@ -699,8 +659,51 @@ public:
     };
 
 private:
-    typedef pair<key_type, mapped_type>                             __value_type;
-    typedef __map_value_compare<key_type, mapped_type, key_compare> __vc;
+
+#if __cplusplus >= 201103L
+    union __value_type
+    {
+        typedef typename map::value_type value_type;
+        typedef typename map::__nc_value_type __nc_value_type;
+        value_type __cc;
+        __nc_value_type __nc;
+
+        template <class ..._Args>
+        __value_type(_Args&& ...__args)
+            : __cc(std::forward<_Args>(__args)...) {}
+
+        __value_type(const __value_type& __v)
+            : __cc(std::move(__v.__cc)) {}
+
+        __value_type(__value_type&& __v)
+            : __nc(std::move(__v.__nc)) {}
+
+        __value_type& operator=(const __value_type& __v)
+            {__nc = __v.__cc; return *this;}
+
+        __value_type& operator=(__value_type&& __v)
+            {__nc = std::move(__v.__nc); return *this;}
+
+        ~__value_type() {__cc.~value_type();}
+    };
+#else
+    struct __value_type
+    {
+        typedef typename map::value_type value_type;
+        value_type __cc;
+
+        __value_type() {}
+
+        template <class _A0>
+        __value_type(const _A0& __a0)
+            : __cc(__a0) {}
+
+        template <class _A0, class _A1>
+        __value_type(const _A0& __a0, const _A1& __a1)
+            : __cc(__a0, __a1) {}
+    };
+#endif
+    typedef __map_value_compare<key_type, __value_type, key_compare> __vc;
     typedef typename allocator_traits<allocator_type>::template
 #ifndef _LIBCPP_HAS_NO_TEMPLATE_ALIASES
             rebind_alloc<__value_type>
@@ -764,7 +767,14 @@ public:
     _LIBCPP_INLINE_VISIBILITY
     map& operator=(const map& __m)
         {
+#if __cplusplus >= 201103L
             __tree_ = __m.__tree_;
+#else
+            __tree_.clear();
+            __tree_.value_comp() = __m.__tree_.value_comp();
+            __tree_.__copy_assign_alloc(__m.__tree_);
+            insert(__m.begin(), __m.end());
+#endif
             return *this;
         }
 
@@ -986,32 +996,17 @@ private:
 #ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES
     __node_holder __construct_node();
     template <class _A0>
-        typename enable_if
-        <
-            is_constructible<value_type, _A0>::value,
-            __node_holder
-        >::type
-         __construct_node(_A0&& __a0);
-    template <class _A0>
-        typename enable_if
-        <
-            is_constructible<key_type, _A0>::value,
-            __node_holder
-        >::type
-         __construct_node(_A0&& __a0);
+        __node_holder __construct_node(_A0&& __a0);
+    __node_holder __construct_node_with_key(key_type&& __k);
 #ifndef _LIBCPP_HAS_NO_VARIADICS
     template <class _A0, class _A1, class ..._Args>
         __node_holder __construct_node(_A0&& __a0, _A1&& __a1, _Args&& ...__args);
 #endif  // _LIBCPP_HAS_NO_VARIADICS
-#else  // _LIBCPP_HAS_NO_RVALUE_REFERENCES
-    __node_holder __construct_node(const key_type& __k);
 #endif
+    __node_holder __construct_node_with_key(const key_type& __k);
 
     __node_base_pointer&
         __find_equal_key(__node_base_pointer& __parent, const key_type& __k);
-    __node_base_pointer&
-        __find_equal_key(const_iterator __hint,
-                         __node_base_pointer& __parent, const key_type& __k);
     __node_base_const_pointer
         __find_equal_key(__node_base_const_pointer& __parent, const key_type& __k) const;
 };
@@ -1030,97 +1025,37 @@ map<_Key, _Tp, _Compare, _Allocator>::__find_equal_key(__node_base_pointer& __pa
     {
         while (true)
         {
-            if (__tree_.value_comp().key_comp()(__k, __nd->__value_.first))
+            if (__tree_.value_comp().key_comp()(__k, __nd->__value_.__cc.first))
             {
                 if (__nd->__left_ != nullptr)
                     __nd = static_cast<__node_pointer>(__nd->__left_);
                 else
                 {
-                    __parent = __nd;
+                    __parent = static_cast<__node_base_pointer>(__nd);
                     return __parent->__left_;
                 }
             }
-            else if (__tree_.value_comp().key_comp()(__nd->__value_.first, __k))
+            else if (__tree_.value_comp().key_comp()(__nd->__value_.__cc.first, __k))
             {
                 if (__nd->__right_ != nullptr)
                     __nd = static_cast<__node_pointer>(__nd->__right_);
                 else
                 {
-                    __parent = __nd;
+                    __parent = static_cast<__node_base_pointer>(__nd);
                     return __parent->__right_;
                 }
             }
             else
             {
-                __parent = __nd;
+                __parent = static_cast<__node_base_pointer>(__nd);
                 return __parent;
             }
         }
     }
-    __parent = __tree_.__end_node();
+    __parent = static_cast<__node_base_pointer>(__tree_.__end_node());
     return __parent->__left_;
 }
 
-// Find place to insert if __k doesn't exist
-// First check prior to __hint.
-// Next check after __hint.
-// Next do O(log N) search.
-// Set __parent to parent of null leaf
-// Return reference to null leaf
-// If __k exists, set parent to node of __k and return reference to node of __k
-template <class _Key, class _Tp, class _Compare, class _Allocator>
-typename map<_Key, _Tp, _Compare, _Allocator>::__node_base_pointer&
-map<_Key, _Tp, _Compare, _Allocator>::__find_equal_key(const_iterator __hint,
-                                                       __node_base_pointer& __parent,
-                                                       const key_type& __k)
-{
-    if (__hint == end() || __tree_.value_comp().key_comp()(__k, __hint->first))  // check before
-    {
-        // __k < *__hint
-        const_iterator __prior = __hint;
-        if (__prior == begin() || __tree_.value_comp().key_comp()((--__prior)->first, __k))
-        {
-            // *prev(__hint) < __k < *__hint
-            if (__hint.__ptr_->__left_ == nullptr)
-            {
-                __parent = const_cast<__node_pointer&>(__hint.__ptr_);
-                return __parent->__left_;
-            }
-            else
-            {
-                __parent = const_cast<__node_pointer&>(__prior.__ptr_);
-                return __parent->__right_;
-            }
-        }
-        // __k <= *prev(__hint)
-        return __find_equal_key(__parent, __k);
-    }
-    else if (__tree_.value_comp().key_comp()(__hint->first, __k))  // check after
-    {
-        // *__hint < __k
-        const_iterator __next = _VSTD::next(__hint);
-        if (__next == end() || __tree_.value_comp().key_comp()(__k, __next->first))
-        {
-            // *__hint < __k < *next(__hint)
-            if (__hint.__ptr_->__right_ == nullptr)
-            {
-                __parent = const_cast<__node_pointer&>(__hint.__ptr_);
-                return __parent->__right_;
-            }
-            else
-            {
-                __parent = const_cast<__node_pointer&>(__next.__ptr_);
-                return __parent->__left_;
-            }
-        }
-        // *next(__hint) <= __k
-        return __find_equal_key(__parent, __k);
-    }
-    // else __k == *__hint
-    __parent = const_cast<__node_pointer&>(__hint.__ptr_);
-    return __parent;
-}
-
 // Find __k
 // Set __parent to parent of null leaf and
 //    return reference to null leaf iv __k does not exist.
@@ -1135,34 +1070,34 @@ map<_Key, _Tp, _Compare, _Allocator>::__find_equal_key(__node_base_const_pointer
     {
         while (true)
         {
-            if (__tree_.value_comp().key_comp()(__k, __nd->__value_.first))
+            if (__tree_.value_comp().key_comp()(__k, __nd->__value_.__cc.first))
             {
                 if (__nd->__left_ != nullptr)
                     __nd = static_cast<__node_pointer>(__nd->__left_);
                 else
                 {
-                    __parent = __nd;
+                    __parent = static_cast<__node_base_pointer>(__nd);
                     return const_cast<const __node_base_const_pointer&>(__parent->__left_);
                 }
             }
-            else if (__tree_.value_comp().key_comp()(__nd->__value_.first, __k))
+            else if (__tree_.value_comp().key_comp()(__nd->__value_.__cc.first, __k))
             {
                 if (__nd->__right_ != nullptr)
                     __nd = static_cast<__node_pointer>(__nd->__right_);
                 else
                 {
-                    __parent = __nd;
+                    __parent = static_cast<__node_base_pointer>(__nd);
                     return const_cast<const __node_base_const_pointer&>(__parent->__right_);
                 }
             }
             else
             {
-                __parent = __nd;
+                __parent = static_cast<__node_base_pointer>(__nd);
                 return __parent;
             }
         }
     }
-    __parent = __tree_.__end_node();
+    __parent = static_cast<__node_base_pointer>(__tree_.__end_node());
     return const_cast<const __node_base_const_pointer&>(__parent->__left_);
 }
 
@@ -1187,20 +1122,16 @@ map<_Key, _Tp, _Compare, _Allocator>::__construct_node()
 {
     __node_allocator& __na = __tree_.__node_alloc();
     __node_holder __h(__node_traits::allocate(__na, 1), _Dp(__na));
-    __node_traits::construct(__na, _VSTD::addressof(__h->__value_.first));
+    __node_traits::construct(__na, _VSTD::addressof(__h->__value_.__cc.first));
     __h.get_deleter().__first_constructed = true;
-    __node_traits::construct(__na, _VSTD::addressof(__h->__value_.second));
+    __node_traits::construct(__na, _VSTD::addressof(__h->__value_.__cc.second));
     __h.get_deleter().__second_constructed = true;
     return __h;
 }
 
 template <class _Key, class _Tp, class _Compare, class _Allocator>
 template <class _A0>
-typename enable_if
-<
-    is_constructible<pair<const _Key, _Tp>, _A0>::value,
-    typename map<_Key, _Tp, _Compare, _Allocator>::__node_holder
->::type
+typename map<_Key, _Tp, _Compare, _Allocator>::__node_holder
 map<_Key, _Tp, _Compare, _Allocator>::__construct_node(_A0&& __a0)
 {
     __node_allocator& __na = __tree_.__node_alloc();
@@ -1212,21 +1143,16 @@ map<_Key, _Tp, _Compare, _Allocator>::__construct_node(_A0&& __a0)
 }
 
 template <class _Key, class _Tp, class _Compare, class _Allocator>
-template <class _A0>
-typename enable_if
-<
-    is_constructible<_Key, _A0>::value,
-    typename map<_Key, _Tp, _Compare, _Allocator>::__node_holder
->::type
-map<_Key, _Tp, _Compare, _Allocator>::__construct_node(_A0&& __a0)
+typename map<_Key, _Tp, _Compare, _Allocator>::__node_holder
+map<_Key, _Tp, _Compare, _Allocator>::__construct_node_with_key(key_type&& __k)
 {
     __node_allocator& __na = __tree_.__node_alloc();
     __node_holder __h(__node_traits::allocate(__na, 1), _Dp(__na));
-    __node_traits::construct(__na, _VSTD::addressof(__h->__value_.first), _VSTD::forward<_A0>(__a0));
+    __node_traits::construct(__na, _VSTD::addressof(__h->__value_.__cc.first), _VSTD::move(__k));
     __h.get_deleter().__first_constructed = true;
-    __node_traits::construct(__na, _VSTD::addressof(__h->__value_.second));
+    __node_traits::construct(__na, _VSTD::addressof(__h->__value_.__cc.second));
     __h.get_deleter().__second_constructed = true;
-    return __h;
+    return _VSTD::move(__h);
 }
 
 #ifndef _LIBCPP_HAS_NO_VARIADICS
@@ -1248,23 +1174,21 @@ map<_Key, _Tp, _Compare, _Allocator>::__construct_node(_A0&& __a0, _A1&& __a1, _
 
 #endif  // _LIBCPP_HAS_NO_VARIADICS
 
-#else  // _LIBCPP_HAS_NO_RVALUE_REFERENCES
+#endif  // _LIBCPP_HAS_NO_RVALUE_REFERENCES
 
 template <class _Key, class _Tp, class _Compare, class _Allocator>
 typename map<_Key, _Tp, _Compare, _Allocator>::__node_holder
-map<_Key, _Tp, _Compare, _Allocator>::__construct_node(const key_type& __k)
+map<_Key, _Tp, _Compare, _Allocator>::__construct_node_with_key(const key_type& __k)
 {
     __node_allocator& __na = __tree_.__node_alloc();
     __node_holder __h(__node_traits::allocate(__na, 1), _Dp(__na));
-    __node_traits::construct(__na, _VSTD::addressof(__h->__value_.first), __k);
+    __node_traits::construct(__na, _VSTD::addressof(__h->__value_.__cc.first), __k);
     __h.get_deleter().__first_constructed = true;
-    __node_traits::construct(__na, _VSTD::addressof(__h->__value_.second));
+    __node_traits::construct(__na, _VSTD::addressof(__h->__value_.__cc.second));
     __h.get_deleter().__second_constructed = true;
     return _VSTD::move(__h);
 }
 
-#endif  // _LIBCPP_HAS_NO_RVALUE_REFERENCES
-
 template <class _Key, class _Tp, class _Compare, class _Allocator>
 _Tp&
 map<_Key, _Tp, _Compare, _Allocator>::operator[](const key_type& __k)
@@ -1274,11 +1198,11 @@ map<_Key, _Tp, _Compare, _Allocator>::operator[](const key_type& __k)
     __node_pointer __r = static_cast<__node_pointer>(__child);
     if (__child == nullptr)
     {
-        __node_holder __h = __construct_node(__k);
-        __tree_.__insert_node_at(__parent, __child, __h.get());
+        __node_holder __h = __construct_node_with_key(__k);
+        __tree_.__insert_node_at(__parent, __child, static_cast<__node_base_pointer>(__h.get()));
         __r = __h.release();
     }
-    return __r->__value_.second;
+    return __r->__value_.__cc.second;
 }
 
 #ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES
@@ -1292,11 +1216,11 @@ map<_Key, _Tp, _Compare, _Allocator>::operator[](key_type&& __k)
     __node_pointer __r = static_cast<__node_pointer>(__child);
     if (__child == nullptr)
     {
-        __node_holder __h = __construct_node(_VSTD::move(__k));
-        __tree_.__insert_node_at(__parent, __child, __h.get());
+        __node_holder __h = __construct_node_with_key(_VSTD::move(__k));
+        __tree_.__insert_node_at(__parent, __child, static_cast<__node_base_pointer>(__h.get()));
         __r = __h.release();
     }
-    return __r->__value_.second;
+    return __r->__value_.__cc.second;
 }
 
 #endif  // _LIBCPP_HAS_NO_RVALUE_REFERENCES
@@ -1311,7 +1235,7 @@ map<_Key, _Tp, _Compare, _Allocator>::at(const key_type& __k)
     if (__child == nullptr)
         throw out_of_range("map::at:  key not found");
 #endif  // _LIBCPP_NO_EXCEPTIONS
-    return static_cast<__node_pointer>(__child)->__value_.second;
+    return static_cast<__node_pointer>(__child)->__value_.__cc.second;
 }
 
 template <class _Key, class _Tp, class _Compare, class _Allocator>
@@ -1324,7 +1248,7 @@ map<_Key, _Tp, _Compare, _Allocator>::at(const key_type& __k) const
     if (__child == nullptr)
         throw out_of_range("map::at:  key not found");
 #endif  // _LIBCPP_NO_EXCEPTIONS
-    return static_cast<__node_const_pointer>(__child)->__value_.second;
+    return static_cast<__node_const_pointer>(__child)->__value_.__cc.second;
 }
 
 #if !defined(_LIBCPP_HAS_NO_RVALUE_REFERENCES) && !defined(_LIBCPP_HAS_NO_VARIADICS)
@@ -1429,6 +1353,7 @@ public:
     typedef _Key                                     key_type;
     typedef _Tp                                      mapped_type;
     typedef pair<const key_type, mapped_type>        value_type;
+    typedef pair<key_type, mapped_type>              __nc_value_type;
     typedef _Compare                                 key_compare;
     typedef _Allocator                               allocator_type;
     typedef value_type&                              reference;
@@ -1450,8 +1375,50 @@ public:
     };
 
 private:
-    typedef pair<key_type, mapped_type>                             __value_type;
-    typedef __map_value_compare<key_type, mapped_type, key_compare> __vc;
+#if __cplusplus >= 201103L
+    union __value_type
+    {
+        typedef typename multimap::value_type value_type;
+        typedef typename multimap::__nc_value_type __nc_value_type;
+        value_type __cc;
+        __nc_value_type __nc;
+
+        template <class ..._Args>
+        __value_type(_Args&& ...__args)
+            : __cc(std::forward<_Args>(__args)...) {}
+
+        __value_type(const __value_type& __v)
+            : __cc(std::move(__v.__cc)) {}
+
+        __value_type(__value_type&& __v)
+            : __nc(std::move(__v.__nc)) {}
+
+        __value_type& operator=(const __value_type& __v)
+            {__nc = __v.__cc; return *this;}
+
+        __value_type& operator=(__value_type&& __v)
+            {__nc = std::move(__v.__nc); return *this;}
+
+        ~__value_type() {__cc.~value_type();}
+    };
+#else
+    struct __value_type
+    {
+        typedef typename multimap::value_type value_type;
+        value_type __cc;
+
+        __value_type() {}
+
+        template <class _A0>
+        __value_type(const _A0& __a0)
+            : __cc(__a0) {}
+
+        template <class _A0, class _A1>
+        __value_type(const _A0& __a0, const _A1& __a1)
+            : __cc(__a0, __a1) {}
+    };
+#endif
+    typedef __map_value_compare<key_type, __value_type, key_compare> __vc;
     typedef typename allocator_traits<allocator_type>::template
 #ifndef _LIBCPP_HAS_NO_TEMPLATE_ALIASES
             rebind_alloc<__value_type>
@@ -1516,7 +1483,14 @@ public:
     _LIBCPP_INLINE_VISIBILITY
     multimap& operator=(const multimap& __m)
         {
+#if __cplusplus >= 201103L
             __tree_ = __m.__tree_;
+#else
+            __tree_.clear();
+            __tree_.value_comp() = __m.__tree_.value_comp();
+            __tree_.__copy_assign_alloc(__m.__tree_);
+            insert(__m.begin(), __m.end());
+#endif
             return *this;
         }
 
@@ -1725,18 +1699,7 @@ private:
 #ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES
     __node_holder __construct_node();
     template <class _A0>
-        typename enable_if
-        <
-            is_constructible<value_type, _A0>::value,
-            __node_holder
-        >::type
-         __construct_node(_A0&& __a0);
-    template <class _A0>
-        typename enable_if
-        <
-            is_constructible<key_type, _A0>::value,
-            __node_holder
-        >::type
+        __node_holder
          __construct_node(_A0&& __a0);
 #ifndef _LIBCPP_HAS_NO_VARIADICS
     template <class _A0, class _A1, class ..._Args>
@@ -1766,20 +1729,16 @@ multimap<_Key, _Tp, _Compare, _Allocator>::__construct_node()
 {
     __node_allocator& __na = __tree_.__node_alloc();
     __node_holder __h(__node_traits::allocate(__na, 1), _Dp(__na));
-    __node_traits::construct(__na, _VSTD::addressof(__h->__value_.first));
+    __node_traits::construct(__na, _VSTD::addressof(__h->__value_.__cc.first));
     __h.get_deleter().__first_constructed = true;
-    __node_traits::construct(__na, _VSTD::addressof(__h->__value_.second));
+    __node_traits::construct(__na, _VSTD::addressof(__h->__value_.__cc.second));
     __h.get_deleter().__second_constructed = true;
     return __h;
 }
 
 template <class _Key, class _Tp, class _Compare, class _Allocator>
 template <class _A0>
-typename enable_if
-<
-    is_constructible<pair<const _Key, _Tp>, _A0>::value,
-    typename multimap<_Key, _Tp, _Compare, _Allocator>::__node_holder
->::type
+typename multimap<_Key, _Tp, _Compare, _Allocator>::__node_holder
 multimap<_Key, _Tp, _Compare, _Allocator>::__construct_node(_A0&& __a0)
 {
     __node_allocator& __na = __tree_.__node_alloc();
@@ -1790,24 +1749,6 @@ multimap<_Key, _Tp, _Compare, _Allocator>::__construct_node(_A0&& __a0)
     return __h;
 }
 
-template <class _Key, class _Tp, class _Compare, class _Allocator>
-template <class _A0>
-typename enable_if
-<
-    is_constructible<_Key, _A0>::value,
-    typename multimap<_Key, _Tp, _Compare, _Allocator>::__node_holder
->::type
-multimap<_Key, _Tp, _Compare, _Allocator>::__construct_node(_A0&& __a0)
-{
-    __node_allocator& __na = __tree_.__node_alloc();
-    __node_holder __h(__node_traits::allocate(__na, 1), _Dp(__na));
-    __node_traits::construct(__na, _VSTD::addressof(__h->__value_.first), _VSTD::forward<_A0>(__a0));
-    __h.get_deleter().__first_constructed = true;
-    __node_traits::construct(__na, _VSTD::addressof(__h->__value_.second));
-    __h.get_deleter().__second_constructed = true;
-    return __h;
-}
-
 #ifndef _LIBCPP_HAS_NO_VARIADICS
 
 template <class _Key, class _Tp, class _Compare, class _Allocator>
diff --git a/include/memory b/include/memory
index 2a8b7e66632f..ffd0cd0ce77d 100644
--- a/include/memory
+++ b/include/memory
@@ -350,6 +350,10 @@ class bad_weak_ptr
     bad_weak_ptr() noexcept;
 };
 
+template<class T, class... Args> unique_ptr<T> make_unique(Args&&... args);     // C++14
+template<class T>                unique_ptr<T> make_unique(size_t n);           // C++14
+template<class T, class... Args> unspecified   make_unique(Args&&...) = delete; // C++14, T == U[N]
+
 template<class T>
 class shared_ptr
 {
@@ -1750,7 +1754,7 @@ public:
     typedef const _Tp*        const_pointer;
     typedef const _Tp&        reference;
     typedef const _Tp&        const_reference;
-    typedef _Tp               value_type;
+    typedef const _Tp         value_type;
 
     typedef true_type propagate_on_container_move_assignment;
 
@@ -2036,6 +2040,10 @@ public:
             return *this;
         }
 
+#endif  // _LIBCPP_HAS_NO_RVALUE_REFERENCES
+
+#endif  // _LIBCPP_HAS_NO_DEFAULTED_FUNCTIONS
+
 #ifndef _LIBCPP_HAS_NO_VARIADICS
 
     template <class... _Args1, class... _Args2, size_t... _I1, size_t... _I2>
@@ -2051,10 +2059,6 @@ public:
 
 #endif  // _LIBCPP_HAS_NO_VARIADICS
 
-#endif  // _LIBCPP_HAS_NO_RVALUE_REFERENCES
-
-#endif  // _LIBCPP_HAS_NO_DEFAULTED_FUNCTIONS
-
     _LIBCPP_INLINE_VISIBILITY _T1_reference       first() _NOEXCEPT       {return __first_;}
     _LIBCPP_INLINE_VISIBILITY _T1_const_reference first() const _NOEXCEPT {return __first_;}
 
@@ -2131,6 +2135,10 @@ public:
             return *this;
         }
 
+#endif  // _LIBCPP_HAS_NO_RVALUE_REFERENCES
+
+#endif  // _LIBCPP_HAS_NO_DEFAULTED_FUNCTIONS
+
 #ifndef _LIBCPP_HAS_NO_VARIADICS
 
     template <class... _Args1, class... _Args2, size_t... _I1, size_t... _I2>
@@ -2146,10 +2154,6 @@ public:
 
 #endif  // _LIBCPP_HAS_NO_VARIADICS
 
-#endif  // _LIBCPP_HAS_NO_RVALUE_REFERENCES
-
-#endif  // _LIBCPP_HAS_NO_DEFAULTED_FUNCTIONS
-
     _LIBCPP_INLINE_VISIBILITY _T1_reference       first() _NOEXCEPT       {return *this;}
     _LIBCPP_INLINE_VISIBILITY _T1_const_reference first() const _NOEXCEPT {return *this;}
 
@@ -2227,6 +2231,10 @@ public:
             return *this;
         }
 
+#endif  // _LIBCPP_HAS_NO_RVALUE_REFERENCES
+
+#endif  // _LIBCPP_HAS_NO_DEFAULTED_FUNCTIONS
+
 #ifndef _LIBCPP_HAS_NO_VARIADICS
 
     template <class... _Args1, class... _Args2, size_t... _I1, size_t... _I2>
@@ -2243,10 +2251,6 @@ public:
 
 #endif  // _LIBCPP_HAS_NO_VARIADICS
 
-#endif  // _LIBCPP_HAS_NO_RVALUE_REFERENCES
-
-#endif  // _LIBCPP_HAS_NO_DEFAULTED_FUNCTIONS
-
     _LIBCPP_INLINE_VISIBILITY _T1_reference       first() _NOEXCEPT       {return __first_;}
     _LIBCPP_INLINE_VISIBILITY _T1_const_reference first() const _NOEXCEPT {return __first_;}
 
@@ -2321,6 +2325,10 @@ public:
             return *this;
         }
 
+#endif  // _LIBCPP_HAS_NO_RVALUE_REFERENCES
+
+#endif  // _LIBCPP_HAS_NO_DEFAULTED_FUNCTIONS
+
 #ifndef _LIBCPP_HAS_NO_VARIADICS
 
     template <class... _Args1, class... _Args2, size_t... _I1, size_t... _I2>
@@ -2336,10 +2344,6 @@ public:
 
 #endif  // _LIBCPP_HAS_NO_VARIADICS
 
-#endif  // _LIBCPP_HAS_NO_RVALUE_REFERENCES
-
-#endif  // _LIBCPP_HAS_NO_DEFAULTED_FUNCTIONS
-
     _LIBCPP_INLINE_VISIBILITY _T1_reference       first() _NOEXCEPT       {return *this;}
     _LIBCPP_INLINE_VISIBILITY _T1_const_reference first() const _NOEXCEPT {return *this;}
 
@@ -2409,6 +2413,10 @@ public:
             return *this;
         }
 
+#endif  // _LIBCPP_HAS_NO_RVALUE_REFERENCES
+
+#endif  // _LIBCPP_HAS_NO_DEFAULTED_FUNCTIONS
+
 #ifndef _LIBCPP_HAS_NO_VARIADICS
 
     template <class... _Args1, class... _Args2>
@@ -2422,10 +2430,6 @@ public:
 
 #endif  // _LIBCPP_HAS_NO_VARIADICS
 
-#endif  // _LIBCPP_HAS_NO_RVALUE_REFERENCES
-
-#endif  // _LIBCPP_HAS_NO_DEFAULTED_FUNCTIONS
-
     _LIBCPP_INLINE_VISIBILITY _T1_reference       first() _NOEXCEPT       {return base::first();}
     _LIBCPP_INLINE_VISIBILITY _T1_const_reference first() const _NOEXCEPT {return base::first();}
 
@@ -3079,8 +3083,61 @@ move(unique_ptr<_Tp, _Dp>& __t)
 
 #endif
 
+#if _LIBCPP_STD_VER > 11
+
+template<class _Tp>
+struct __unique_if
+{
+    typedef unique_ptr<_Tp> __unique_single;
+};
+
+template<class _Tp>
+struct __unique_if<_Tp[]>
+{
+    typedef unique_ptr<_Tp[]> __unique_array_unknown_bound;
+};
+
+template<class _Tp, size_t _Np>
+struct __unique_if<_Tp[_Np]>
+{
+    typedef void __unique_array_known_bound;
+};
+
+template<class _Tp, class... _Args>
+inline _LIBCPP_INLINE_VISIBILITY
+typename __unique_if<_Tp>::__unique_single
+make_unique(_Args&&... __args)
+{
+    return unique_ptr<_Tp>(new _Tp(_VSTD::forward<_Args>(__args)...));
+}
+
+template<class _Tp>
+inline _LIBCPP_INLINE_VISIBILITY
+typename __unique_if<_Tp>::__unique_array_unknown_bound
+make_unique(size_t __n)
+{
+    typedef typename remove_extent<_Tp>::type _Up;
+    return unique_ptr<_Tp>(new _Up[__n]());
+}
+
+template<class _Tp, class... _Args>
+    typename __unique_if<_Tp>::__unique_array_known_bound
+    make_unique(_Args&&...) = delete;
+
+#endif  // _LIBCPP_STD_VER > 11
+
 template <class _Tp> struct hash;
 
+template <class _Size>
+inline _LIBCPP_INLINE_VISIBILITY
+_Size
+__loadword(const void* __p)
+{
+    _Size __r;
+    std::memcpy(&__r, __p, sizeof(__r));
+    return __r;
+}
+
 // We use murmur2 when size_t is 32 bits, and cityhash64 when size_t
 // is 64 bits.  This is because cityhash64 uses 64bit x 64bit
 // multiplication, which can be very slow on 32-bit systems.
@@ -3104,7 +3161,7 @@ __murmur2_or_cityhash<_Size, 32>::operator()(const void* __key, _Size __len)
     const unsigned char* __data = static_cast<const unsigned char*>(__key);
     for (; __len >= 4; __data += 4, __len -= 4)
     {
-        _Size __k = *(const _Size*)__data;
+        _Size __k = __loadword<_Size>(__data);
         __k *= __m;
         __k ^= __k >> __r;
         __k *= __m;
@@ -3163,13 +3220,13 @@ struct __murmur2_or_cityhash<_Size, 64>
 
   static _Size __hash_len_0_to_16(const char* __s, _Size __len) {
     if (__len > 8) {
-      const _Size __a = *(const _Size*)__s;
-      const _Size __b = *(const _Size*)(__s + __len - 8);
+      const _Size __a = __loadword<_Size>(__s);
+      const _Size __b = __loadword<_Size>(__s + __len - 8);
       return __hash_len_16(__a, __rotate_by_at_least_1(__b + __len, __len)) ^ __b;
     }
     if (__len >= 4) {
-      const uint32_t __a = *(const uint32_t*)(__s);
-      const uint32_t __b = *(const uint32_t*)(__s + __len - 4);
+      const uint32_t __a = __loadword<uint32_t>(__s);
+      const uint32_t __b = __loadword<uint32_t>(__s + __len - 4);
       return __hash_len_16(__len + (__a << 3), __b);
     }
     if (__len > 0) {
@@ -3185,10 +3242,10 @@ struct __murmur2_or_cityhash<_Size, 64>
   }
 
   static _Size __hash_len_17_to_32(const char *__s, _Size __len) {
-    const _Size __a = *(const _Size*)(__s) * __k1;
-    const _Size __b = *(const _Size*)(__s + 8);
-    const _Size __c = *(const _Size*)(__s + __len - 8) * __k2;
-    const _Size __d = *(const _Size*)(__s + __len - 16) * __k0;
+    const _Size __a = __loadword<_Size>(__s) * __k1;
+    const _Size __b = __loadword<_Size>(__s + 8);
+    const _Size __c = __loadword<_Size>(__s + __len - 8) * __k2;
+    const _Size __d = __loadword<_Size>(__s + __len - 16) * __k0;
     return __hash_len_16(__rotate(__a - __b, 43) + __rotate(__c, 30) + __d,
                          __a + __rotate(__b ^ __k3, 20) - __c + __len);
   }
@@ -3209,33 +3266,33 @@ struct __murmur2_or_cityhash<_Size, 64>
   // Return a 16-byte hash for s[0] ... s[31], a, and b.  Quick and dirty.
   static pair<_Size, _Size> __weak_hash_len_32_with_seeds(
       const char* __s, _Size __a, _Size __b) {
-    return __weak_hash_len_32_with_seeds(*(const _Size*)(__s),
-                                         *(const _Size*)(__s + 8),
-                                         *(const _Size*)(__s + 16),
-                                         *(const _Size*)(__s + 24),
+    return __weak_hash_len_32_with_seeds(__loadword<_Size>(__s),
+                                         __loadword<_Size>(__s + 8),
+                                         __loadword<_Size>(__s + 16),
+                                         __loadword<_Size>(__s + 24),
                                          __a,
                                          __b);
   }
 
   // Return an 8-byte hash for 33 to 64 bytes.
   static _Size __hash_len_33_to_64(const char *__s, size_t __len) {
-    _Size __z = *(const _Size*)(__s + 24);
-    _Size __a = *(const _Size*)(__s) +
-                (__len + *(const _Size*)(__s + __len - 16)) * __k0;
+    _Size __z = __loadword<_Size>(__s + 24);
+    _Size __a = __loadword<_Size>(__s) +
+                (__len + __loadword<_Size>(__s + __len - 16)) * __k0;
     _Size __b = __rotate(__a + __z, 52);
     _Size __c = __rotate(__a, 37);
-    __a += *(const _Size*)(__s + 8);
+    __a += __loadword<_Size>(__s + 8);
     __c += __rotate(__a, 7);
-    __a += *(const _Size*)(__s + 16);
+    __a += __loadword<_Size>(__s + 16);
     _Size __vf = __a + __z;
     _Size __vs = __b + __rotate(__a, 31) + __c;
-    __a = *(const _Size*)(__s + 16) + *(const _Size*)(__s + __len - 32);
-    __z += *(const _Size*)(__s + __len - 8);
+    __a = __loadword<_Size>(__s + 16) + __loadword<_Size>(__s + __len - 32);
+    __z += __loadword<_Size>(__s + __len - 8);
     __b = __rotate(__a + __z, 52);
     __c = __rotate(__a, 37);
-    __a += *(const _Size*)(__s + __len - 24);
+    __a += __loadword<_Size>(__s + __len - 24);
     __c += __rotate(__a, 7);
-    __a += *(const _Size*)(__s + __len - 16);
+    __a += __loadword<_Size>(__s + __len - 16);
     _Size __wf = __a + __z;
     _Size __ws = __b + __rotate(__a, 31) + __c;
     _Size __r = __shift_mix((__vf + __ws) * __k2 + (__wf + __vs) * __k0);
@@ -3261,26 +3318,26 @@ __murmur2_or_cityhash<_Size, 64>::operator()(const void* __key, _Size __len)
 
   // For strings over 64 bytes we hash the end first, and then as we
   // loop we keep 56 bytes of state: v, w, x, y, and z.
-  _Size __x = *(const _Size*)(__s + __len - 40);
-  _Size __y = *(const _Size*)(__s + __len - 16) +
-              *(const _Size*)(__s + __len - 56);
-  _Size __z = __hash_len_16(*(const _Size*)(__s + __len - 48) + __len,
-                          *(const _Size*)(__s + __len - 24));
+  _Size __x = __loadword<_Size>(__s + __len - 40);
+  _Size __y = __loadword<_Size>(__s + __len - 16) +
+              __loadword<_Size>(__s + __len - 56);
+  _Size __z = __hash_len_16(__loadword<_Size>(__s + __len - 48) + __len,
+                          __loadword<_Size>(__s + __len - 24));
   pair<_Size, _Size> __v = __weak_hash_len_32_with_seeds(__s + __len - 64, __len, __z);
   pair<_Size, _Size> __w = __weak_hash_len_32_with_seeds(__s + __len - 32, __y + __k1, __x);
-  __x = __x * __k1 + *(const _Size*)(__s);
+  __x = __x * __k1 + __loadword<_Size>(__s);
 
   // Decrease len to the nearest multiple of 64, and operate on 64-byte chunks.
   __len = (__len - 1) & ~static_cast<_Size>(63);
   do {
-    __x = __rotate(__x + __y + __v.first + *(const _Size*)(__s + 8), 37) * __k1;
-    __y = __rotate(__y + __v.second + *(const _Size*)(__s + 48), 42) * __k1;
+    __x = __rotate(__x + __y + __v.first + __loadword<_Size>(__s + 8), 37) * __k1;
+    __y = __rotate(__y + __v.second + __loadword<_Size>(__s + 48), 42) * __k1;
     __x ^= __w.second;
-    __y += __v.first + *(const _Size*)(__s + 40);
+    __y += __v.first + __loadword<_Size>(__s + 40);
     __z = __rotate(__z + __w.first, 33) * __k1;
     __v = __weak_hash_len_32_with_seeds(__s, __v.second * __k1, __x + __w.first);
     __w = __weak_hash_len_32_with_seeds(__s + 32, __z + __w.second,
-                                        __y + *(const _Size*)(__s + 16));
+                                        __y + __loadword<_Size>(__s + 16));
     std::swap(__z, __x);
     __s += 64;
     __len -= 64;
diff --git a/include/random b/include/random
index 92722ea64e73..46cbc4bdc647 100644
--- a/include/random
+++ b/include/random
@@ -1880,7 +1880,7 @@ public:
         seed(_Sseq& __q)
             {__seed(__q, integral_constant<unsigned,
                 1 + (__m == 0 ? (sizeof(result_type) * __CHAR_BIT__ - 1)/32
-                             :  (__m-1) / 0x100000000ull)>());}
+                             :  (__m > 0x100000000ull))>());}
 
     // generating functions
     _LIBCPP_INLINE_VISIBILITY
@@ -1969,7 +1969,7 @@ linear_congruential_engine<_UIntType, __a, __c, __m>::__seed(_Sseq& __q,
     uint32_t __ar[__k+3];
     __q.generate(__ar, __ar + __k + 3);
     result_type __s = static_cast<result_type>((__ar[3] +
-                                                (uint64_t)__ar[4] << 32) % __m);
+                                              ((uint64_t)__ar[4] << 32)) % __m);
     __x_ = __c == 0 && __s == 0 ? result_type(1) : __s;
 }
 
diff --git a/include/regex b/include/regex
index d1afa54a894f..312ca11442f1 100644
--- a/include/regex
+++ b/include/regex
@@ -2843,6 +2843,15 @@ private:
                  const basic_regex<_Cp, _Tp>& __e,
                  regex_constants::match_flag_type __flags);
 
+    template <class _Iter, class _Ap, class _Cp, class _Tp>
+    friend
+    bool
+    regex_search(__wrap_iter<_Iter> __first,
+                 __wrap_iter<_Iter> __last,
+                 match_results<__wrap_iter<_Iter>, _Ap>& __m,
+                 const basic_regex<_Cp, _Tp>& __e,
+                 regex_constants::match_flag_type __flags);
+
     template <class, class> friend class __lookahead;
 };
 
@@ -2921,7 +2930,7 @@ __lookahead<_CharT, _Traits>::__exec(__state& __s) const
     bool __matched = __exp_.__match_at_start_ecma(__s.__current_, __s.__last_,
                                                   __m,
                                                   __s.__flags_ | regex_constants::match_continuous,
-                                                  true);
+                                                  __s.__at_first_ && __s.__current_ == __s.__first_);
     if (__matched != __invert_)
     {
         __s.__do_ = __state::__accept_but_not_consume;
@@ -3420,6 +3429,7 @@ basic_regex<_CharT, _Traits>::__parse_QUOTED_CHAR_ERE(_ForwardIterator __first,
                 case '+':
                 case '?':
                 case '{':
+                case '}':
                     __push_char(*__temp);
                     __first = ++__temp;
                     break;
@@ -3903,7 +3913,7 @@ basic_regex<_CharT, _Traits>::__parse_awk_escape(_ForwardIterator __first,
         {
             __val = 8 * __val + *__first - '0';
             if (++__first != __last && ('0' <= *__first && *__first <= '7'))
-                __val = 8 * __val + *__first - '0';
+                __val = 8 * __val + *__first++ - '0';
         }
         if (__str)
             *__str = _CharT(__val);
@@ -4481,7 +4491,7 @@ basic_regex<_CharT, _Traits>::__parse_character_escape(_ForwardIterator __first,
                 ++__first;
             }
 #ifndef _LIBCPP_NO_EXCEPTIONS
-            else if (__str)
+            else
                 throw regex_error(regex_constants::error_escape);
 #endif  // _LIBCPP_NO_EXCEPTIONS
             break;
@@ -5807,6 +5817,21 @@ regex_search(_BidirectionalIterator __first, _BidirectionalIterator __last,
     return __r;
 }
 
+template <class _Iter, class _Allocator, class _CharT, class _Traits>
+inline _LIBCPP_INLINE_VISIBILITY
+bool
+regex_search(__wrap_iter<_Iter> __first,
+             __wrap_iter<_Iter> __last,
+             match_results<__wrap_iter<_Iter>, _Allocator>& __m,
+             const basic_regex<_CharT, _Traits>& __e,
+             regex_constants::match_flag_type __flags = regex_constants::match_default)
+{
+    match_results<const _CharT*> __mc;
+    bool __r = __e.__search(__first.base(), __last.base(), __mc, __flags);
+    __m.__assign(__first, __last, __mc, __flags & regex_constants::__no_update_pos);
+    return __r;
+}
+
 template <class _Allocator, class _CharT, class _Traits>
 inline _LIBCPP_INLINE_VISIBILITY
 bool
@@ -6044,7 +6069,7 @@ regex_iterator<_BidirectionalIterator, _CharT, _Traits>::operator++()
 {
     __flags_ |= regex_constants::__no_update_pos;
     _BidirectionalIterator __start = __match_[0].second;
-    if (__match_.length() == 0)
+    if (__match_.empty())
     {
         if (__start == __end_)
         {
diff --git a/include/string b/include/string
index fa44f68e3883..89f75cd2ed01 100644
--- a/include/string
+++ b/include/string
@@ -100,8 +100,8 @@ public:
         noexcept(is_nothrow_move_constructible<allocator_type>::value);
     basic_string(const basic_string& str, size_type pos, size_type n = npos,
                  const allocator_type& a = allocator_type());
-    basic_string(const_pointer s, const allocator_type& a = allocator_type());
-    basic_string(const_pointer s, size_type n, const allocator_type& a = allocator_type());
+    basic_string(const value_type* s, const allocator_type& a = allocator_type());
+    basic_string(const value_type* s, size_type n, const allocator_type& a = allocator_type());
     basic_string(size_type n, value_type c, const allocator_type& a = allocator_type());
     template<class InputIterator>
         basic_string(InputIterator begin, InputIterator end,
@@ -117,7 +117,7 @@ public:
         noexcept(
              allocator_type::propagate_on_container_move_assignment::value &&
              is_nothrow_move_assignable<allocator_type>::value);
-    basic_string& operator=(const_pointer s);
+    basic_string& operator=(const value_type* s);
     basic_string& operator=(value_type c);
     basic_string& operator=(initializer_list<value_type>);
 
@@ -156,14 +156,14 @@ public:
     reference       at(size_type n);
 
     basic_string& operator+=(const basic_string& str);
-    basic_string& operator+=(const_pointer s);
+    basic_string& operator+=(const value_type* s);
     basic_string& operator+=(value_type c);
     basic_string& operator+=(initializer_list<value_type>);
 
     basic_string& append(const basic_string& str);
     basic_string& append(const basic_string& str, size_type pos, size_type n);
-    basic_string& append(const_pointer s, size_type n);
-    basic_string& append(const_pointer s);
+    basic_string& append(const value_type* s, size_type n);
+    basic_string& append(const value_type* s);
     basic_string& append(size_type n, value_type c);
     template<class InputIterator>
         basic_string& append(InputIterator first, InputIterator last);
@@ -179,8 +179,8 @@ public:
     basic_string& assign(const basic_string& str);
     basic_string& assign(basic_string&& str);
     basic_string& assign(const basic_string& str, size_type pos, size_type n);
-    basic_string& assign(const_pointer s, size_type n);
-    basic_string& assign(const_pointer s);
+    basic_string& assign(const value_type* s, size_type n);
+    basic_string& assign(const value_type* s);
     basic_string& assign(size_type n, value_type c);
     template<class InputIterator>
         basic_string& assign(InputIterator first, InputIterator last);
@@ -189,8 +189,8 @@ public:
     basic_string& insert(size_type pos1, const basic_string& str);
     basic_string& insert(size_type pos1, const basic_string& str,
                          size_type pos2, size_type n);
-    basic_string& insert(size_type pos, const_pointer s, size_type n);
-    basic_string& insert(size_type pos, const_pointer s);
+    basic_string& insert(size_type pos, const value_type* s, size_type n);
+    basic_string& insert(size_type pos, const value_type* s);
     basic_string& insert(size_type pos, size_type n, value_type c);
     iterator      insert(const_iterator p, value_type c);
     iterator      insert(const_iterator p, size_type n, value_type c);
@@ -205,66 +205,66 @@ public:
     basic_string& replace(size_type pos1, size_type n1, const basic_string& str);
     basic_string& replace(size_type pos1, size_type n1, const basic_string& str,
                           size_type pos2, size_type n2);
-    basic_string& replace(size_type pos, size_type n1, const_pointer s, size_type n2);
-    basic_string& replace(size_type pos, size_type n1, const_pointer s);
+    basic_string& replace(size_type pos, size_type n1, const value_type* s, size_type n2);
+    basic_string& replace(size_type pos, size_type n1, const value_type* s);
     basic_string& replace(size_type pos, size_type n1, size_type n2, value_type c);
     basic_string& replace(const_iterator i1, const_iterator i2, const basic_string& str);
-    basic_string& replace(const_iterator i1, const_iterator i2, const_pointer s, size_type n);
-    basic_string& replace(const_iterator i1, const_iterator i2, const_pointer s);
+    basic_string& replace(const_iterator i1, const_iterator i2, const value_type* s, size_type n);
+    basic_string& replace(const_iterator i1, const_iterator i2, const value_type* s);
     basic_string& replace(const_iterator i1, const_iterator i2, size_type n, value_type c);
     template<class InputIterator>
         basic_string& replace(const_iterator i1, const_iterator i2, InputIterator j1, InputIterator j2);
     basic_string& replace(const_iterator i1, const_iterator i2, initializer_list<value_type>);
 
-    size_type copy(pointer s, size_type n, size_type pos = 0) const;
+    size_type copy(value_type* s, size_type n, size_type pos = 0) const;
     basic_string substr(size_type pos = 0, size_type n = npos) const;
 
     void swap(basic_string& str)
         noexcept(!allocator_type::propagate_on_container_swap::value ||
                  __is_nothrow_swappable<allocator_type>::value)
 
-    const_pointer c_str() const noexcept;
-    const_pointer data() const noexcept;
+    const value_type* c_str() const noexcept;
+    const value_type* data() const noexcept;
 
     allocator_type get_allocator() const noexcept;
 
     size_type find(const basic_string& str, size_type pos = 0) const noexcept;
-    size_type find(const_pointer s, size_type pos, size_type n) const noexcept;
-    size_type find(const_pointer s, size_type pos = 0) const noexcept;
+    size_type find(const value_type* s, size_type pos, size_type n) const noexcept;
+    size_type find(const value_type* s, size_type pos = 0) const noexcept;
     size_type find(value_type c, size_type pos = 0) const noexcept;
 
     size_type rfind(const basic_string& str, size_type pos = npos) const noexcept;
-    size_type rfind(const_pointer s, size_type pos, size_type n) const noexcept;
-    size_type rfind(const_pointer s, size_type pos = npos) const noexcept;
+    size_type rfind(const value_type* s, size_type pos, size_type n) const noexcept;
+    size_type rfind(const value_type* s, size_type pos = npos) const noexcept;
     size_type rfind(value_type c, size_type pos = npos) const noexcept;
 
     size_type find_first_of(const basic_string& str, size_type pos = 0) const noexcept;
-    size_type find_first_of(const_pointer s, size_type pos, size_type n) const noexcept;
-    size_type find_first_of(const_pointer s, size_type pos = 0) const noexcept;
+    size_type find_first_of(const value_type* s, size_type pos, size_type n) const noexcept;
+    size_type find_first_of(const value_type* s, size_type pos = 0) const noexcept;
     size_type find_first_of(value_type c, size_type pos = 0) const noexcept;
 
     size_type find_last_of(const basic_string& str, size_type pos = npos) const noexcept;
-    size_type find_last_of(const_pointer s, size_type pos, size_type n) const noexcept;
-    size_type find_last_of(const_pointer s, size_type pos = npos) const noexcept;
+    size_type find_last_of(const value_type* s, size_type pos, size_type n) const noexcept;
+    size_type find_last_of(const value_type* s, size_type pos = npos) const noexcept;
     size_type find_last_of(value_type c, size_type pos = npos) const noexcept;
 
     size_type find_first_not_of(const basic_string& str, size_type pos = 0) const noexcept;
-    size_type find_first_not_of(const_pointer s, size_type pos, size_type n) const noexcept;
-    size_type find_first_not_of(const_pointer s, size_type pos = 0) const noexcept;
+    size_type find_first_not_of(const value_type* s, size_type pos, size_type n) const noexcept;
+    size_type find_first_not_of(const value_type* s, size_type pos = 0) const noexcept;
     size_type find_first_not_of(value_type c, size_type pos = 0) const noexcept;
 
     size_type find_last_not_of(const basic_string& str, size_type pos = npos) const noexcept;
-    size_type find_last_not_of(const_pointer s, size_type pos, size_type n) const noexcept;
-    size_type find_last_not_of(const_pointer s, size_type pos = npos) const noexcept;
+    size_type find_last_not_of(const value_type* s, size_type pos, size_type n) const noexcept;
+    size_type find_last_not_of(const value_type* s, size_type pos = npos) const noexcept;
     size_type find_last_not_of(value_type c, size_type pos = npos) const noexcept;
 
     int compare(const basic_string& str) const noexcept;
     int compare(size_type pos1, size_type n1, const basic_string& str) const;
     int compare(size_type pos1, size_type n1, const basic_string& str,
                 size_type pos2, size_type n2) const;
-    int compare(const_pointer s) const noexcept;
-    int compare(size_type pos1, size_type n1, const_pointer s) const;
-    int compare(size_type pos1, size_type n1, const_pointer s, size_type n2) const;
+    int compare(const value_type* s) const noexcept;
+    int compare(size_type pos1, size_type n1, const value_type* s) const;
+    int compare(size_type pos1, size_type n1, const value_type* s, size_type n2) const;
 
     bool __invariants() const;
 };
@@ -1036,6 +1036,21 @@ _LIBCPP_EXTERN_TEMPLATE(class __basic_string_common<true>)
 #pragma warning( pop )
 #endif // _MSC_VER
 
+#ifdef _LIBCPP_ALTERNATE_STRING_LAYOUT
+
+template <class _CharT, size_t = sizeof(_CharT)>
+struct __padding
+{
+    unsigned char __xx[sizeof(_CharT)-1];
+};
+
+template <class _CharT>
+struct __padding<_CharT, 1>
+{
+};
+
+#endif  // _LIBCPP_ALTERNATE_STRING_LAYOUT
+
 template<class _CharT, class _Traits, class _Allocator>
 class _LIBCPP_TYPE_VIS basic_string
     : private __basic_string_common<true>
@@ -1069,6 +1084,39 @@ public:
     typedef _VSTD::reverse_iterator<const_iterator>       const_reverse_iterator;
 
 private:
+
+#ifdef _LIBCPP_ALTERNATE_STRING_LAYOUT
+
+    struct __long
+    {
+        pointer   __data_;
+        size_type __size_;
+        size_type __cap_;
+    };
+
+#if _LIBCPP_BIG_ENDIAN
+    enum {__short_mask = 0x01};
+    enum {__long_mask  = 0x1ul};
+#else  // _LIBCPP_BIG_ENDIAN
+    enum {__short_mask = 0x80};
+    enum {__long_mask  = ~(size_type(~0) >> 1)};
+#endif  // _LIBCPP_BIG_ENDIAN
+
+    enum {__min_cap = (sizeof(__long) - 1)/sizeof(value_type) > 2 ?
+                      (sizeof(__long) - 1)/sizeof(value_type) : 2};
+
+    struct __short
+    {
+        value_type __data_[__min_cap];
+        struct
+            : __padding<value_type>
+        {
+            unsigned char __size_;
+        };
+    };
+
+#else
+
     struct __long
     {
         size_type __cap_;
@@ -1084,8 +1132,6 @@ private:
     enum {__long_mask  = 0x1ul};
 #endif  // _LIBCPP_BIG_ENDIAN
 
-    enum {__mask = size_type(~0) >> 1};
-
     enum {__min_cap = (sizeof(__long) - 1)/sizeof(value_type) > 2 ?
                       (sizeof(__long) - 1)/sizeof(value_type) : 2};
 
@@ -1099,6 +1145,8 @@ private:
         value_type __data_[__min_cap];
     };
 
+#endif  // _LIBCPP_ALTERNATE_STRING_LAYOUT
+
     union __lx{__long __lx; __short __lxx;};
 
     enum {__n_words = sizeof(__lx) / sizeof(size_type)};
@@ -1144,13 +1192,13 @@ public:
     _LIBCPP_INLINE_VISIBILITY
     basic_string(basic_string&& __str, const allocator_type& __a);
 #endif  // _LIBCPP_HAS_NO_RVALUE_REFERENCES
-    _LIBCPP_INLINE_VISIBILITY basic_string(const_pointer __s);
+    _LIBCPP_INLINE_VISIBILITY basic_string(const value_type* __s);
     _LIBCPP_INLINE_VISIBILITY
-    basic_string(const_pointer __s, const allocator_type& __a);
+    basic_string(const value_type* __s, const allocator_type& __a);
     _LIBCPP_INLINE_VISIBILITY
-    basic_string(const_pointer __s, size_type __n);
+    basic_string(const value_type* __s, size_type __n);
     _LIBCPP_INLINE_VISIBILITY
-    basic_string(const_pointer __s, size_type __n, const allocator_type& __a);
+    basic_string(const value_type* __s, size_type __n, const allocator_type& __a);
     _LIBCPP_INLINE_VISIBILITY
     basic_string(size_type __n, value_type __c);
     _LIBCPP_INLINE_VISIBILITY
@@ -1179,7 +1227,7 @@ public:
         _NOEXCEPT_(__alloc_traits::propagate_on_container_move_assignment::value &&
                    is_nothrow_move_assignable<allocator_type>::value);
 #endif
-    _LIBCPP_INLINE_VISIBILITY basic_string& operator=(const_pointer __s) {return assign(__s);}
+    _LIBCPP_INLINE_VISIBILITY basic_string& operator=(const value_type* __s) {return assign(__s);}
     basic_string& operator=(value_type __c);
 #ifndef _LIBCPP_HAS_NO_GENERALIZED_INITIALIZERS
     _LIBCPP_INLINE_VISIBILITY
@@ -1192,13 +1240,13 @@ public:
         {return iterator(__get_pointer());}
     _LIBCPP_INLINE_VISIBILITY
     const_iterator begin() const _NOEXCEPT
-        {return const_iterator(data());}
+        {return const_iterator(__get_pointer());}
     _LIBCPP_INLINE_VISIBILITY
     iterator end() _NOEXCEPT
         {return iterator(__get_pointer() + size());}
     _LIBCPP_INLINE_VISIBILITY
     const_iterator end() const _NOEXCEPT
-        {return const_iterator(data() + size());}
+        {return const_iterator(__get_pointer() + size());}
 #else  // _LIBCPP_DEBUG
     _LIBCPP_INLINE_VISIBILITY iterator       begin()       {return iterator(this, __get_pointer());}
     _LIBCPP_INLINE_VISIBILITY const_iterator begin() const {return const_iterator(this, data());}
@@ -1255,7 +1303,7 @@ public:
     reference       at(size_type __n);
 
     _LIBCPP_INLINE_VISIBILITY basic_string& operator+=(const basic_string& __str) {return append(__str);}
-    _LIBCPP_INLINE_VISIBILITY basic_string& operator+=(const_pointer __s)         {return append(__s);}
+    _LIBCPP_INLINE_VISIBILITY basic_string& operator+=(const value_type* __s)         {return append(__s);}
     _LIBCPP_INLINE_VISIBILITY basic_string& operator+=(value_type __c)            {push_back(__c); return *this;}
 #ifndef _LIBCPP_HAS_NO_GENERALIZED_INITIALIZERS
     _LIBCPP_INLINE_VISIBILITY basic_string& operator+=(initializer_list<value_type> __il) {return append(__il);}
@@ -1264,8 +1312,8 @@ public:
     _LIBCPP_INLINE_VISIBILITY
     basic_string& append(const basic_string& __str);
     basic_string& append(const basic_string& __str, size_type __pos, size_type __n);
-    basic_string& append(const_pointer __s, size_type __n);
-    basic_string& append(const_pointer __s);
+    basic_string& append(const value_type* __s, size_type __n);
+    basic_string& append(const value_type* __s);
     basic_string& append(size_type __n, value_type __c);
     template<class _InputIterator>
         typename enable_if
@@ -1303,8 +1351,8 @@ public:
         {*this = _VSTD::move(str); return *this;}
 #endif
     basic_string& assign(const basic_string& __str, size_type __pos, size_type __n);
-    basic_string& assign(const_pointer __s, size_type __n);
-    basic_string& assign(const_pointer __s);
+    basic_string& assign(const value_type* __s, size_type __n);
+    basic_string& assign(const value_type* __s);
     basic_string& assign(size_type __n, value_type __c);
     template<class _InputIterator>
         typename enable_if
@@ -1329,8 +1377,8 @@ public:
     _LIBCPP_INLINE_VISIBILITY
     basic_string& insert(size_type __pos1, const basic_string& __str);
     basic_string& insert(size_type __pos1, const basic_string& __str, size_type __pos2, size_type __n);
-    basic_string& insert(size_type __pos, const_pointer __s, size_type __n);
-    basic_string& insert(size_type __pos, const_pointer __s);
+    basic_string& insert(size_type __pos, const value_type* __s, size_type __n);
+    basic_string& insert(size_type __pos, const value_type* __s);
     basic_string& insert(size_type __pos, size_type __n, value_type __c);
     iterator      insert(const_iterator __pos, value_type __c);
     _LIBCPP_INLINE_VISIBILITY
@@ -1365,15 +1413,15 @@ public:
     _LIBCPP_INLINE_VISIBILITY
     basic_string& replace(size_type __pos1, size_type __n1, const basic_string& __str);
     basic_string& replace(size_type __pos1, size_type __n1, const basic_string& __str, size_type __pos2, size_type __n2);
-    basic_string& replace(size_type __pos, size_type __n1, const_pointer __s, size_type __n2);
-    basic_string& replace(size_type __pos, size_type __n1, const_pointer __s);
+    basic_string& replace(size_type __pos, size_type __n1, const value_type* __s, size_type __n2);
+    basic_string& replace(size_type __pos, size_type __n1, const value_type* __s);
     basic_string& replace(size_type __pos, size_type __n1, size_type __n2, value_type __c);
     _LIBCPP_INLINE_VISIBILITY
     basic_string& replace(const_iterator __i1, const_iterator __i2, const basic_string& __str);
     _LIBCPP_INLINE_VISIBILITY
-    basic_string& replace(const_iterator __i1, const_iterator __i2, const_pointer __s, size_type __n);
+    basic_string& replace(const_iterator __i1, const_iterator __i2, const value_type* __s, size_type __n);
     _LIBCPP_INLINE_VISIBILITY
-    basic_string& replace(const_iterator __i1, const_iterator __i2, const_pointer __s);
+    basic_string& replace(const_iterator __i1, const_iterator __i2, const value_type* __s);
     _LIBCPP_INLINE_VISIBILITY
     basic_string& replace(const_iterator __i1, const_iterator __i2, size_type __n, value_type __c);
     template<class _InputIterator>
@@ -1389,7 +1437,7 @@ public:
         {return replace(__i1, __i2, __il.begin(), __il.end());}
 #endif  // _LIBCPP_HAS_NO_GENERALIZED_INITIALIZERS
 
-    size_type copy(pointer __s, size_type __n, size_type __pos = 0) const;
+    size_type copy(value_type* __s, size_type __n, size_type __pos = 0) const;
     _LIBCPP_INLINE_VISIBILITY
     basic_string substr(size_type __pos = 0, size_type __n = npos) const;
 
@@ -1399,56 +1447,56 @@ public:
                    __is_nothrow_swappable<allocator_type>::value);
 
     _LIBCPP_INLINE_VISIBILITY
-    const_pointer c_str() const _NOEXCEPT {return data();}
+    const value_type* c_str() const _NOEXCEPT {return data();}
     _LIBCPP_INLINE_VISIBILITY
-    const_pointer data() const _NOEXCEPT  {return __get_pointer();}
+    const value_type* data() const _NOEXCEPT  {return _VSTD::__to_raw_pointer(__get_pointer());}
 
     _LIBCPP_INLINE_VISIBILITY
     allocator_type get_allocator() const _NOEXCEPT {return __alloc();}
 
     _LIBCPP_INLINE_VISIBILITY
     size_type find(const basic_string& __str, size_type __pos = 0) const _NOEXCEPT;
-    size_type find(const_pointer __s, size_type __pos, size_type __n) const _NOEXCEPT;
+    size_type find(const value_type* __s, size_type __pos, size_type __n) const _NOEXCEPT;
     _LIBCPP_INLINE_VISIBILITY
-    size_type find(const_pointer __s, size_type __pos = 0) const _NOEXCEPT;
+    size_type find(const value_type* __s, size_type __pos = 0) const _NOEXCEPT;
     size_type find(value_type __c, size_type __pos = 0) const _NOEXCEPT;
 
     _LIBCPP_INLINE_VISIBILITY
     size_type rfind(const basic_string& __str, size_type __pos = npos) const _NOEXCEPT;
-    size_type rfind(const_pointer __s, size_type __pos, size_type __n) const _NOEXCEPT;
+    size_type rfind(const value_type* __s, size_type __pos, size_type __n) const _NOEXCEPT;
     _LIBCPP_INLINE_VISIBILITY
-    size_type rfind(const_pointer __s, size_type __pos = npos) const _NOEXCEPT;
+    size_type rfind(const value_type* __s, size_type __pos = npos) const _NOEXCEPT;
     size_type rfind(value_type __c, size_type __pos = npos) const _NOEXCEPT;
 
     _LIBCPP_INLINE_VISIBILITY
     size_type find_first_of(const basic_string& __str, size_type __pos = 0) const _NOEXCEPT;
-    size_type find_first_of(const_pointer __s, size_type __pos, size_type __n) const _NOEXCEPT;
+    size_type find_first_of(const value_type* __s, size_type __pos, size_type __n) const _NOEXCEPT;
     _LIBCPP_INLINE_VISIBILITY
-    size_type find_first_of(const_pointer __s, size_type __pos = 0) const _NOEXCEPT;
+    size_type find_first_of(const value_type* __s, size_type __pos = 0) const _NOEXCEPT;
     _LIBCPP_INLINE_VISIBILITY
     size_type find_first_of(value_type __c, size_type __pos = 0) const _NOEXCEPT;
 
     _LIBCPP_INLINE_VISIBILITY
     size_type find_last_of(const basic_string& __str, size_type __pos = npos) const _NOEXCEPT;
-    size_type find_last_of(const_pointer __s, size_type __pos, size_type __n) const _NOEXCEPT;
+    size_type find_last_of(const value_type* __s, size_type __pos, size_type __n) const _NOEXCEPT;
     _LIBCPP_INLINE_VISIBILITY
-    size_type find_last_of(const_pointer __s, size_type __pos = npos) const _NOEXCEPT;
+    size_type find_last_of(const value_type* __s, size_type __pos = npos) const _NOEXCEPT;
     _LIBCPP_INLINE_VISIBILITY
     size_type find_last_of(value_type __c, size_type __pos = npos) const _NOEXCEPT;
 
     _LIBCPP_INLINE_VISIBILITY
     size_type find_first_not_of(const basic_string& __str, size_type __pos = 0) const _NOEXCEPT;
-    size_type find_first_not_of(const_pointer __s, size_type __pos, size_type __n) const _NOEXCEPT;
+    size_type find_first_not_of(const value_type* __s, size_type __pos, size_type __n) const _NOEXCEPT;
     _LIBCPP_INLINE_VISIBILITY
-    size_type find_first_not_of(const_pointer __s, size_type __pos = 0) const _NOEXCEPT;
+    size_type find_first_not_of(const value_type* __s, size_type __pos = 0) const _NOEXCEPT;
     _LIBCPP_INLINE_VISIBILITY
     size_type find_first_not_of(value_type __c, size_type __pos = 0) const _NOEXCEPT;
 
     _LIBCPP_INLINE_VISIBILITY
     size_type find_last_not_of(const basic_string& __str, size_type __pos = npos) const _NOEXCEPT;
-    size_type find_last_not_of(const_pointer __s, size_type __pos, size_type __n) const _NOEXCEPT;
+    size_type find_last_not_of(const value_type* __s, size_type __pos, size_type __n) const _NOEXCEPT;
     _LIBCPP_INLINE_VISIBILITY
-    size_type find_last_not_of(const_pointer __s, size_type __pos = npos) const _NOEXCEPT;
+    size_type find_last_not_of(const value_type* __s, size_type __pos = npos) const _NOEXCEPT;
     _LIBCPP_INLINE_VISIBILITY
     size_type find_last_not_of(value_type __c, size_type __pos = npos) const _NOEXCEPT;
 
@@ -1457,9 +1505,9 @@ public:
     _LIBCPP_INLINE_VISIBILITY
     int compare(size_type __pos1, size_type __n1, const basic_string& __str) const;
     int compare(size_type __pos1, size_type __n1, const basic_string& __str, size_type __pos2, size_type __n2) const;
-    int compare(const_pointer __s) const _NOEXCEPT;
-    int compare(size_type __pos1, size_type __n1, const_pointer __s) const;
-    int compare(size_type __pos1, size_type __n1, const_pointer __s, size_type __n2) const;
+    int compare(const value_type* __s) const _NOEXCEPT;
+    int compare(size_type __pos1, size_type __n1, const value_type* __s) const;
+    int compare(size_type __pos1, size_type __n1, const value_type* __s, size_type __n2) const;
 
     _LIBCPP_INLINE_VISIBILITY bool __invariants() const;
 
@@ -1475,20 +1523,44 @@ private:
     const allocator_type& __alloc() const _NOEXCEPT
         {return __r_.second();}
 
+#ifdef _LIBCPP_ALTERNATE_STRING_LAYOUT
+
     _LIBCPP_INLINE_VISIBILITY
     void __set_short_size(size_type __s) _NOEXCEPT
-#if _LIBCPP_BIG_ENDIAN
+#   if _LIBCPP_BIG_ENDIAN
+        {__r_.first().__s.__size_ = (unsigned char)(__s << 1);}
+#   else
         {__r_.first().__s.__size_ = (unsigned char)(__s);}
-#else
+#   endif
+
+    _LIBCPP_INLINE_VISIBILITY
+    size_type __get_short_size() const _NOEXCEPT
+#   if _LIBCPP_BIG_ENDIAN
+        {return __r_.first().__s.__size_ >> 1;}
+#   else
+        {return __r_.first().__s.__size_;}
+#   endif
+
+#else  // _LIBCPP_ALTERNATE_STRING_LAYOUT
+
+    _LIBCPP_INLINE_VISIBILITY
+    void __set_short_size(size_type __s) _NOEXCEPT
+#   if _LIBCPP_BIG_ENDIAN
+        {__r_.first().__s.__size_ = (unsigned char)(__s);}
+#   else
         {__r_.first().__s.__size_ = (unsigned char)(__s << 1);}
-#endif
+#   endif
+
     _LIBCPP_INLINE_VISIBILITY
     size_type __get_short_size() const _NOEXCEPT
-#if _LIBCPP_BIG_ENDIAN
+#   if _LIBCPP_BIG_ENDIAN
         {return __r_.first().__s.__size_;}
-#else
+#   else
         {return __r_.first().__s.__size_ >> 1;}
-#endif
+#   endif
+
+#endif  // _LIBCPP_ALTERNATE_STRING_LAYOUT
+
     _LIBCPP_INLINE_VISIBILITY
     void __set_long_size(size_type __s) _NOEXCEPT
         {__r_.first().__l.__size_ = __s;}
@@ -1517,10 +1589,10 @@ private:
         {return __r_.first().__l.__data_;}
     _LIBCPP_INLINE_VISIBILITY
     pointer __get_short_pointer() _NOEXCEPT
-        {return __r_.first().__s.__data_;}
+        {return pointer_traits<pointer>::pointer_to(__r_.first().__s.__data_[0]);}
     _LIBCPP_INLINE_VISIBILITY
     const_pointer __get_short_pointer() const _NOEXCEPT
-        {return __r_.first().__s.__data_;}
+        {return pointer_traits<const_pointer>::pointer_to(__r_.first().__s.__data_[0]);}
     _LIBCPP_INLINE_VISIBILITY
     pointer __get_pointer() _NOEXCEPT
         {return __is_long() ? __get_long_pointer() : __get_short_pointer();}
@@ -1547,8 +1619,8 @@ private:
                  __align<sizeof(value_type) < __alignment ?
                             __alignment/sizeof(value_type) : 1 > (__s+1)) - 1;}
 
-    void __init(const_pointer __s, size_type __sz, size_type __reserve);
-    void __init(const_pointer __s, size_type __sz);
+    void __init(const value_type* __s, size_type __sz, size_type __reserve);
+    void __init(const value_type* __s, size_type __sz);
     void __init(size_type __n, value_type __c);
 
     template <class _InputIterator>
@@ -1572,7 +1644,7 @@ private:
                    size_type __n_copy,  size_type __n_del,     size_type __n_add = 0);
     void __grow_by_and_replace(size_type __old_cap, size_type __delta_cap, size_type __old_sz,
                                size_type __n_copy,  size_type __n_del,
-                               size_type __n_add, const_pointer __p_new_stuff);
+                               size_type __n_add, const value_type* __p_new_stuff);
 
     _LIBCPP_INLINE_VISIBILITY
     void __erase_to_end(size_type __pos);
@@ -1729,7 +1801,7 @@ basic_string<_CharT, _Traits, _Allocator>::basic_string(const allocator_type& __
 
 template <class _CharT, class _Traits, class _Allocator>
 void
-basic_string<_CharT, _Traits, _Allocator>::__init(const_pointer __s, size_type __sz, size_type __reserve)
+basic_string<_CharT, _Traits, _Allocator>::__init(const value_type* __s, size_type __sz, size_type __reserve)
 {
     if (__reserve > max_size())
         this->__throw_length_error();
@@ -1747,13 +1819,13 @@ basic_string<_CharT, _Traits, _Allocator>::__init(const_pointer __s, size_type _
         __set_long_cap(__cap+1);
         __set_long_size(__sz);
     }
-    traits_type::copy(__p, __s, __sz);
+    traits_type::copy(_VSTD::__to_raw_pointer(__p), __s, __sz);
     traits_type::assign(__p[__sz], value_type());
 }
 
 template <class _CharT, class _Traits, class _Allocator>
 void
-basic_string<_CharT, _Traits, _Allocator>::__init(const_pointer __s, size_type __sz)
+basic_string<_CharT, _Traits, _Allocator>::__init(const value_type* __s, size_type __sz)
 {
     if (__sz > max_size())
         this->__throw_length_error();
@@ -1771,13 +1843,13 @@ basic_string<_CharT, _Traits, _Allocator>::__init(const_pointer __s, size_type _
         __set_long_cap(__cap+1);
         __set_long_size(__sz);
     }
-    traits_type::copy(__p, __s, __sz);
+    traits_type::copy(_VSTD::__to_raw_pointer(__p), __s, __sz);
     traits_type::assign(__p[__sz], value_type());
 }
 
 template <class _CharT, class _Traits, class _Allocator>
 _LIBCPP_INLINE_VISIBILITY inline
-basic_string<_CharT, _Traits, _Allocator>::basic_string(const_pointer __s)
+basic_string<_CharT, _Traits, _Allocator>::basic_string(const value_type* __s)
 {
 #ifdef _LIBCPP_DEBUG
     assert(__s != 0);
@@ -1787,7 +1859,7 @@ basic_string<_CharT, _Traits, _Allocator>::basic_string(const_pointer __s)
 
 template <class _CharT, class _Traits, class _Allocator>
 _LIBCPP_INLINE_VISIBILITY inline
-basic_string<_CharT, _Traits, _Allocator>::basic_string(const_pointer __s, const allocator_type& __a)
+basic_string<_CharT, _Traits, _Allocator>::basic_string(const value_type* __s, const allocator_type& __a)
     : __r_(__a)
 {
 #ifdef _LIBCPP_DEBUG
@@ -1798,7 +1870,7 @@ basic_string<_CharT, _Traits, _Allocator>::basic_string(const_pointer __s, const
 
 template <class _CharT, class _Traits, class _Allocator>
 _LIBCPP_INLINE_VISIBILITY inline
-basic_string<_CharT, _Traits, _Allocator>::basic_string(const_pointer __s, size_type __n)
+basic_string<_CharT, _Traits, _Allocator>::basic_string(const value_type* __s, size_type __n)
 {
 #ifdef _LIBCPP_DEBUG
     assert(__s != 0);
@@ -1808,7 +1880,7 @@ basic_string<_CharT, _Traits, _Allocator>::basic_string(const_pointer __s, size_
 
 template <class _CharT, class _Traits, class _Allocator>
 _LIBCPP_INLINE_VISIBILITY inline
-basic_string<_CharT, _Traits, _Allocator>::basic_string(const_pointer __s, size_type __n, const allocator_type& __a)
+basic_string<_CharT, _Traits, _Allocator>::basic_string(const value_type* __s, size_type __n, const allocator_type& __a)
     : __r_(__a)
 {
 #ifdef _LIBCPP_DEBUG
@@ -1824,7 +1896,7 @@ basic_string<_CharT, _Traits, _Allocator>::basic_string(const basic_string& __st
     if (!__str.__is_long())
         __r_.first().__r = __str.__r_.first().__r;
     else
-        __init(__str.__get_long_pointer(), __str.__get_long_size());
+        __init(_VSTD::__to_raw_pointer(__str.__get_long_pointer()), __str.__get_long_size());
 }
 
 template <class _CharT, class _Traits, class _Allocator>
@@ -1834,7 +1906,7 @@ basic_string<_CharT, _Traits, _Allocator>::basic_string(const basic_string& __st
     if (!__str.__is_long())
         __r_.first().__r = __str.__r_.first().__r;
     else
-        __init(__str.__get_long_pointer(), __str.__get_long_size());
+        __init(_VSTD::__to_raw_pointer(__str.__get_long_pointer()), __str.__get_long_size());
 }
 
 #ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES
@@ -1859,7 +1931,7 @@ basic_string<_CharT, _Traits, _Allocator>::basic_string(basic_string&& __str, co
     if (__a == __str.__alloc() || !__str.__is_long())
         __r_.first().__r = __str.__r_.first().__r;
     else
-        __init(__str.__get_long_pointer(), __str.__get_long_size());
+        __init(_VSTD::__to_raw_pointer(__str.__get_long_pointer()), __str.__get_long_size());
     __str.__zero();
 #ifdef _LIBCPP_DEBUG
     __str.__invalidate_all_iterators();
@@ -1888,7 +1960,7 @@ basic_string<_CharT, _Traits, _Allocator>::__init(size_type __n, value_type __c)
         __set_long_cap(__cap+1);
         __set_long_size(__n);
     }
-    traits_type::assign(__p, __n, __c);
+    traits_type::assign(_VSTD::__to_raw_pointer(__p), __n, __c);
     traits_type::assign(__p[__n], value_type());
 }
 
@@ -2026,7 +2098,7 @@ template <class _CharT, class _Traits, class _Allocator>
 void
 basic_string<_CharT, _Traits, _Allocator>::__grow_by_and_replace
     (size_type __old_cap, size_type __delta_cap, size_type __old_sz,
-     size_type __n_copy,  size_type __n_del,     size_type __n_add, const_pointer __p_new_stuff)
+     size_type __n_copy,  size_type __n_del,     size_type __n_add, const value_type* __p_new_stuff)
 {
     size_type __ms = max_size();
     if (__delta_cap > __ms - __old_cap - 1)
@@ -2038,12 +2110,14 @@ basic_string<_CharT, _Traits, _Allocator>::__grow_by_and_replace
     pointer __p = __alloc_traits::allocate(__alloc(), __cap+1);
     __invalidate_all_iterators();
     if (__n_copy != 0)
-        traits_type::copy(__p, __old_p, __n_copy);
+        traits_type::copy(_VSTD::__to_raw_pointer(__p),
+                          _VSTD::__to_raw_pointer(__old_p), __n_copy);
     if (__n_add != 0)
-        traits_type::copy(__p + __n_copy, __p_new_stuff, __n_add);
+        traits_type::copy(_VSTD::__to_raw_pointer(__p) + __n_copy, __p_new_stuff, __n_add);
     size_type __sec_cp_sz = __old_sz - __n_del - __n_copy;
     if (__sec_cp_sz != 0)
-        traits_type::copy(__p + __n_copy + __n_add, __old_p + __n_copy + __n_del, __sec_cp_sz);
+        traits_type::copy(_VSTD::__to_raw_pointer(__p) + __n_copy + __n_add,
+                          _VSTD::__to_raw_pointer(__old_p) + __n_copy + __n_del, __sec_cp_sz);
     if (__old_cap+1 != __min_cap)
         __alloc_traits::deallocate(__alloc(), __old_p, __old_cap+1);
     __set_long_pointer(__p);
@@ -2068,10 +2142,13 @@ basic_string<_CharT, _Traits, _Allocator>::__grow_by(size_type __old_cap, size_t
     pointer __p = __alloc_traits::allocate(__alloc(), __cap+1);
     __invalidate_all_iterators();
     if (__n_copy != 0)
-        traits_type::copy(__p, __old_p, __n_copy);
+        traits_type::copy(_VSTD::__to_raw_pointer(__p),
+                          _VSTD::__to_raw_pointer(__old_p), __n_copy);
     size_type __sec_cp_sz = __old_sz - __n_del - __n_copy;
     if (__sec_cp_sz != 0)
-        traits_type::copy(__p + __n_copy + __n_add, __old_p + __n_copy + __n_del, __sec_cp_sz);
+        traits_type::copy(_VSTD::__to_raw_pointer(__p) + __n_copy + __n_add,
+                          _VSTD::__to_raw_pointer(__old_p) + __n_copy + __n_del,
+                          __sec_cp_sz);
     if (__old_cap+1 != __min_cap)
         __alloc_traits::deallocate(__alloc(), __old_p, __old_cap+1);
     __set_long_pointer(__p);
@@ -2082,7 +2159,7 @@ basic_string<_CharT, _Traits, _Allocator>::__grow_by(size_type __old_cap, size_t
 
 template <class _CharT, class _Traits, class _Allocator>
 basic_string<_CharT, _Traits, _Allocator>&
-basic_string<_CharT, _Traits, _Allocator>::assign(const_pointer __s, size_type __n)
+basic_string<_CharT, _Traits, _Allocator>::assign(const value_type* __s, size_type __n)
 {
 #ifdef _LIBCPP_DEBUG
     assert(__s != 0);
@@ -2090,7 +2167,7 @@ basic_string<_CharT, _Traits, _Allocator>::assign(const_pointer __s, size_type _
     size_type __cap = capacity();
     if (__cap >= __n)
     {
-        pointer __p = __get_pointer();
+        value_type* __p = _VSTD::__to_raw_pointer(__get_pointer());
         traits_type::move(__p, __s, __n);
         traits_type::assign(__p[__n], value_type());
         __set_size(__n);
@@ -2116,7 +2193,7 @@ basic_string<_CharT, _Traits, _Allocator>::assign(size_type __n, value_type __c)
     }
     else
         __invalidate_iterators_past(__n);
-    pointer __p = __get_pointer();
+    value_type* __p = _VSTD::__to_raw_pointer(__get_pointer());
     traits_type::assign(__p, __n, __c);
     traits_type::assign(__p[__n], value_type());
     __set_size(__n);
@@ -2258,7 +2335,7 @@ basic_string<_CharT, _Traits, _Allocator>::assign(const basic_string& __str, siz
 
 template <class _CharT, class _Traits, class _Allocator>
 basic_string<_CharT, _Traits, _Allocator>&
-basic_string<_CharT, _Traits, _Allocator>::assign(const_pointer __s)
+basic_string<_CharT, _Traits, _Allocator>::assign(const value_type* __s)
 {
 #ifdef _LIBCPP_DEBUG
     assert(__s != 0);
@@ -2270,7 +2347,7 @@ basic_string<_CharT, _Traits, _Allocator>::assign(const_pointer __s)
 
 template <class _CharT, class _Traits, class _Allocator>
 basic_string<_CharT, _Traits, _Allocator>&
-basic_string<_CharT, _Traits, _Allocator>::append(const_pointer __s, size_type __n)
+basic_string<_CharT, _Traits, _Allocator>::append(const value_type* __s, size_type __n)
 {
 #ifdef _LIBCPP_DEBUG
     assert(__s != 0);
@@ -2281,7 +2358,7 @@ basic_string<_CharT, _Traits, _Allocator>::append(const_pointer __s, size_type _
     {
         if (__n)
         {
-            pointer __p = __get_pointer();
+            value_type* __p = _VSTD::__to_raw_pointer(__get_pointer());
             traits_type::copy(__p + __sz, __s, __n);
             __sz += __n;
             __set_size(__sz);
@@ -2304,7 +2381,7 @@ basic_string<_CharT, _Traits, _Allocator>::append(size_type __n, value_type __c)
         if (__cap - __sz < __n)
             __grow_by(__cap, __sz + __n - __cap, __sz, __sz, 0);
         pointer __p = __get_pointer();
-        traits_type::assign(__p + __sz, __n, __c);
+        traits_type::assign(_VSTD::__to_raw_pointer(__p) + __sz, __n, __c);
         __sz += __n;
         __set_size(__sz);
         traits_type::assign(__p[__sz], value_type());
@@ -2316,14 +2393,37 @@ template <class _CharT, class _Traits, class _Allocator>
 void
 basic_string<_CharT, _Traits, _Allocator>::push_back(value_type __c)
 {
-    size_type __cap = capacity();
-    size_type __sz = size();
+    bool __is_short = !__is_long();
+    size_type __cap;
+    size_type __sz;
+    if (__is_short)
+    {
+        __cap = __min_cap - 1;
+        __sz = __get_short_size();
+    }
+    else
+    {
+        __cap = __get_long_cap() - 1;
+        __sz = __get_long_size();
+    }
     if (__sz == __cap)
+    {
         __grow_by(__cap, 1, __sz, __sz, 0);
-    pointer __p = __get_pointer() + __sz;
+        __is_short = !__is_long();
+    }
+    pointer __p;
+    if (__is_short)
+    {
+        __p = __get_short_pointer() + __sz;
+        __set_short_size(__sz+1);
+    }
+    else
+    {
+        __p = __get_long_pointer() + __sz;
+        __set_long_size(__sz+1);
+    }
     traits_type::assign(*__p, __c);
     traits_type::assign(*++__p, value_type());
-    __set_size(__sz+1);
 }
 
 template <class _CharT, class _Traits, class _Allocator>
@@ -2386,7 +2486,7 @@ basic_string<_CharT, _Traits, _Allocator>::append(const basic_string& __str, siz
 
 template <class _CharT, class _Traits, class _Allocator>
 basic_string<_CharT, _Traits, _Allocator>&
-basic_string<_CharT, _Traits, _Allocator>::append(const_pointer __s)
+basic_string<_CharT, _Traits, _Allocator>::append(const value_type* __s)
 {
 #ifdef _LIBCPP_DEBUG
     assert(__s != 0);
@@ -2398,7 +2498,7 @@ basic_string<_CharT, _Traits, _Allocator>::append(const_pointer __s)
 
 template <class _CharT, class _Traits, class _Allocator>
 basic_string<_CharT, _Traits, _Allocator>&
-basic_string<_CharT, _Traits, _Allocator>::insert(size_type __pos, const_pointer __s, size_type __n)
+basic_string<_CharT, _Traits, _Allocator>::insert(size_type __pos, const value_type* __s, size_type __n)
 {
 #ifdef _LIBCPP_DEBUG
     assert(__s != 0);
@@ -2411,7 +2511,7 @@ basic_string<_CharT, _Traits, _Allocator>::insert(size_type __pos, const_pointer
     {
         if (__n)
         {
-            pointer __p = __get_pointer();
+            value_type* __p = _VSTD::__to_raw_pointer(__get_pointer());
             size_type __n_move = __sz - __pos;
             if (__n_move != 0)
             {
@@ -2440,10 +2540,10 @@ basic_string<_CharT, _Traits, _Allocator>::insert(size_type __pos, size_type __n
     if (__n)
     {
         size_type __cap = capacity();
-        pointer __p;
+        value_type* __p;
         if (__cap - __sz >= __n)
         {
-            __p = __get_pointer();
+            __p = _VSTD::__to_raw_pointer(__get_pointer());
             size_type __n_move = __sz - __pos;
             if (__n_move != 0)
                 traits_type::move(__p + __pos + __n, __p + __pos, __n_move);
@@ -2451,7 +2551,7 @@ basic_string<_CharT, _Traits, _Allocator>::insert(size_type __pos, size_type __n
         else
         {
             __grow_by(__cap, __sz + __n - __cap, __sz, __pos, 0, __n);
-            __p = __get_long_pointer();
+            __p = _VSTD::__to_raw_pointer(__get_long_pointer());
         }
         traits_type::assign(__p + __pos, __n, __c);
         __sz += __n;
@@ -2495,10 +2595,10 @@ basic_string<_CharT, _Traits, _Allocator>::insert(const_iterator __pos, _Forward
     size_type __n = static_cast<size_type>(_VSTD::distance(__first, __last));
     if (__n)
     {
-        pointer __p;
+        value_type* __p;
         if (__cap - __sz >= __n)
         {
-            __p = __get_pointer();
+            __p = _VSTD::__to_raw_pointer(__get_pointer());
             size_type __n_move = __sz - __ip;
             if (__n_move != 0)
                 traits_type::move(__p + __ip + __n, __p + __ip, __n_move);
@@ -2506,7 +2606,7 @@ basic_string<_CharT, _Traits, _Allocator>::insert(const_iterator __pos, _Forward
         else
         {
             __grow_by(__cap, __sz + __n - __cap, __sz, __ip, 0, __n);
-            __p = __get_long_pointer();
+            __p = _VSTD::__to_raw_pointer(__get_long_pointer());
         }
         __sz += __n;
         __set_size(__sz);
@@ -2538,7 +2638,7 @@ basic_string<_CharT, _Traits, _Allocator>::insert(size_type __pos1, const basic_
 
 template <class _CharT, class _Traits, class _Allocator>
 basic_string<_CharT, _Traits, _Allocator>&
-basic_string<_CharT, _Traits, _Allocator>::insert(size_type __pos, const_pointer __s)
+basic_string<_CharT, _Traits, _Allocator>::insert(size_type __pos, const value_type* __s)
 {
 #ifdef _LIBCPP_DEBUG
     assert(__s != 0);
@@ -2553,15 +2653,15 @@ basic_string<_CharT, _Traits, _Allocator>::insert(const_iterator __pos, value_ty
     size_type __ip = static_cast<size_type>(__pos - begin());
     size_type __sz = size();
     size_type __cap = capacity();
-    pointer __p;
+    value_type* __p;
     if (__cap == __sz)
     {
         __grow_by(__cap, 1, __sz, __ip, 0, 1);
-        __p = __get_long_pointer();
+        __p = _VSTD::__to_raw_pointer(__get_long_pointer());
     }
     else
     {
-        __p = __get_pointer();
+        __p = _VSTD::__to_raw_pointer(__get_pointer());
         size_type __n_move = __sz - __ip;
         if (__n_move != 0)
             traits_type::move(__p + __ip + 1, __p + __ip, __n_move);
@@ -2586,7 +2686,7 @@ basic_string<_CharT, _Traits, _Allocator>::insert(const_iterator __pos, size_typ
 
 template <class _CharT, class _Traits, class _Allocator>
 basic_string<_CharT, _Traits, _Allocator>&
-basic_string<_CharT, _Traits, _Allocator>::replace(size_type __pos, size_type __n1, const_pointer __s, size_type __n2)
+basic_string<_CharT, _Traits, _Allocator>::replace(size_type __pos, size_type __n1, const value_type* __s, size_type __n2)
 {
 #ifdef _LIBCPP_DEBUG
     assert(__s != 0);
@@ -2598,7 +2698,7 @@ basic_string<_CharT, _Traits, _Allocator>::replace(size_type __pos, size_type __
     size_type __cap = capacity();
     if (__cap - __sz + __n1 >= __n2)
     {
-        pointer __p = __get_pointer();
+        value_type* __p = _VSTD::__to_raw_pointer(__get_pointer());
         if (__n1 != __n2)
         {
             size_type __n_move = __sz - __pos - __n1;
@@ -2647,10 +2747,10 @@ basic_string<_CharT, _Traits, _Allocator>::replace(size_type __pos, size_type __
         this->__throw_out_of_range();
     __n1 = _VSTD::min(__n1, __sz - __pos);
     size_type __cap = capacity();
-    pointer __p;
+    value_type* __p;
     if (__cap - __sz + __n1 >= __n2)
     {
-        __p = __get_pointer();
+        __p = _VSTD::__to_raw_pointer(__get_pointer());
         if (__n1 != __n2)
         {
             size_type __n_move = __sz - __pos - __n1;
@@ -2661,7 +2761,7 @@ basic_string<_CharT, _Traits, _Allocator>::replace(size_type __pos, size_type __
     else
     {
         __grow_by(__cap, __sz - __n1 + __n2 - __cap, __sz, __pos, __n1, __n2);
-        __p = __get_long_pointer();
+        __p = _VSTD::__to_raw_pointer(__get_long_pointer());
     }
     traits_type::assign(__p + __pos, __n2, __c);
     __sz += __n2 - __n1;
@@ -2720,7 +2820,7 @@ basic_string<_CharT, _Traits, _Allocator>::replace(size_type __pos1, size_type _
 
 template <class _CharT, class _Traits, class _Allocator>
 basic_string<_CharT, _Traits, _Allocator>&
-basic_string<_CharT, _Traits, _Allocator>::replace(size_type __pos, size_type __n1, const_pointer __s)
+basic_string<_CharT, _Traits, _Allocator>::replace(size_type __pos, size_type __n1, const value_type* __s)
 {
 #ifdef _LIBCPP_DEBUG
     assert(__s != 0);
@@ -2740,7 +2840,7 @@ basic_string<_CharT, _Traits, _Allocator>::replace(const_iterator __i1, const_it
 template <class _CharT, class _Traits, class _Allocator>
 _LIBCPP_INLINE_VISIBILITY inline
 basic_string<_CharT, _Traits, _Allocator>&
-basic_string<_CharT, _Traits, _Allocator>::replace(const_iterator __i1, const_iterator __i2, const_pointer __s, size_type __n)
+basic_string<_CharT, _Traits, _Allocator>::replace(const_iterator __i1, const_iterator __i2, const value_type* __s, size_type __n)
 {
     return replace(static_cast<size_type>(__i1 - begin()), static_cast<size_type>(__i2 - __i1), __s, __n);
 }
@@ -2748,7 +2848,7 @@ basic_string<_CharT, _Traits, _Allocator>::replace(const_iterator __i1, const_it
 template <class _CharT, class _Traits, class _Allocator>
 _LIBCPP_INLINE_VISIBILITY inline
 basic_string<_CharT, _Traits, _Allocator>&
-basic_string<_CharT, _Traits, _Allocator>::replace(const_iterator __i1, const_iterator __i2, const_pointer __s)
+basic_string<_CharT, _Traits, _Allocator>::replace(const_iterator __i1, const_iterator __i2, const value_type* __s)
 {
     return replace(static_cast<size_type>(__i1 - begin()), static_cast<size_type>(__i2 - __i1), __s);
 }
@@ -2772,7 +2872,7 @@ basic_string<_CharT, _Traits, _Allocator>::erase(size_type __pos, size_type __n)
         this->__throw_out_of_range();
     if (__n)
     {
-        pointer __p = __get_pointer();
+        value_type* __p = _VSTD::__to_raw_pointer(__get_pointer());
         __n = _VSTD::min(__n, __sz - __pos);
         size_type __n_move = __sz - __pos - __n;
         if (__n_move != 0)
@@ -2930,7 +3030,7 @@ basic_string<_CharT, _Traits, _Allocator>::reserve(size_type __res_arg)
                     return;
                 }
             #else  // _LIBCPP_NO_EXCEPTIONS
-                if (__new_data == 0)
+                if (__new_data == nullptr)
                     return;
             #endif  // _LIBCPP_NO_EXCEPTIONS
             }
@@ -2938,7 +3038,8 @@ basic_string<_CharT, _Traits, _Allocator>::reserve(size_type __res_arg)
             __was_long = __is_long();
             __p = __get_pointer();
         }
-        traits_type::copy(__new_data, __p, size()+1);
+        traits_type::copy(_VSTD::__to_raw_pointer(__new_data),
+                          _VSTD::__to_raw_pointer(__p), size()+1);
         if (__was_long)
             __alloc_traits::deallocate(__alloc(), __p, __cap+1);
         if (__now_long)
@@ -3039,7 +3140,7 @@ basic_string<_CharT, _Traits, _Allocator>::back() const
 
 template <class _CharT, class _Traits, class _Allocator>
 typename basic_string<_CharT, _Traits, _Allocator>::size_type
-basic_string<_CharT, _Traits, _Allocator>::copy(pointer __s, size_type __n, size_type __pos) const
+basic_string<_CharT, _Traits, _Allocator>::copy(value_type* __s, size_type __n, size_type __pos) const
 {
     size_type __sz = size();
     if (__pos > __sz)
@@ -3085,7 +3186,7 @@ struct _LIBCPP_HIDDEN __traits_eq
 
 template<class _CharT, class _Traits, class _Allocator>
 typename basic_string<_CharT, _Traits, _Allocator>::size_type
-basic_string<_CharT, _Traits, _Allocator>::find(const_pointer __s,
+basic_string<_CharT, _Traits, _Allocator>::find(const value_type* __s,
                                                 size_type __pos,
                                                 size_type __n) const _NOEXCEPT
 {
@@ -3097,8 +3198,8 @@ basic_string<_CharT, _Traits, _Allocator>::find(const_pointer __s,
         return npos;
     if (__n == 0)
         return __pos;
-    const_pointer __p = data();
-    const_pointer __r = _VSTD::search(__p + __pos, __p + __sz, __s, __s + __n,
+    const value_type* __p = data();
+    const value_type* __r = _VSTD::search(__p + __pos, __p + __sz, __s, __s + __n,
                                      __traits_eq<traits_type>());
     if (__r == __p + __sz)
         return npos;
@@ -3117,7 +3218,7 @@ basic_string<_CharT, _Traits, _Allocator>::find(const basic_string& __str,
 template<class _CharT, class _Traits, class _Allocator>
 _LIBCPP_INLINE_VISIBILITY inline
 typename basic_string<_CharT, _Traits, _Allocator>::size_type
-basic_string<_CharT, _Traits, _Allocator>::find(const_pointer __s,
+basic_string<_CharT, _Traits, _Allocator>::find(const value_type* __s,
                                                 size_type __pos) const _NOEXCEPT
 {
 #ifdef _LIBCPP_DEBUG
@@ -3134,8 +3235,8 @@ basic_string<_CharT, _Traits, _Allocator>::find(value_type __c,
     size_type __sz = size();
     if (__pos >= __sz)
         return npos;
-    const_pointer __p = data();
-    const_pointer __r = traits_type::find(__p + __pos, __sz - __pos, __c);
+    const value_type* __p = data();
+    const value_type* __r = traits_type::find(__p + __pos, __sz - __pos, __c);
     if (__r == 0)
         return npos;
     return static_cast<size_type>(__r - __p);
@@ -3145,7 +3246,7 @@ basic_string<_CharT, _Traits, _Allocator>::find(value_type __c,
 
 template<class _CharT, class _Traits, class _Allocator>
 typename basic_string<_CharT, _Traits, _Allocator>::size_type
-basic_string<_CharT, _Traits, _Allocator>::rfind(const_pointer __s,
+basic_string<_CharT, _Traits, _Allocator>::rfind(const value_type* __s,
                                                  size_type __pos,
                                                  size_type __n) const _NOEXCEPT
 {
@@ -3158,8 +3259,8 @@ basic_string<_CharT, _Traits, _Allocator>::rfind(const_pointer __s,
         __pos += __n;
     else
         __pos = __sz;
-    const_pointer __p = data();
-    const_pointer __r = _VSTD::find_end(__p, __p + __pos, __s, __s + __n,
+    const value_type* __p = data();
+    const value_type* __r = _VSTD::find_end(__p, __p + __pos, __s, __s + __n,
                                        __traits_eq<traits_type>());
     if (__n > 0 && __r == __p + __pos)
         return npos;
@@ -3178,7 +3279,7 @@ basic_string<_CharT, _Traits, _Allocator>::rfind(const basic_string& __str,
 template<class _CharT, class _Traits, class _Allocator>
 _LIBCPP_INLINE_VISIBILITY inline
 typename basic_string<_CharT, _Traits, _Allocator>::size_type
-basic_string<_CharT, _Traits, _Allocator>::rfind(const_pointer __s,
+basic_string<_CharT, _Traits, _Allocator>::rfind(const value_type* __s,
                                                  size_type __pos) const _NOEXCEPT
 {
 #ifdef _LIBCPP_DEBUG
@@ -3199,8 +3300,8 @@ basic_string<_CharT, _Traits, _Allocator>::rfind(value_type __c,
             ++__pos;
         else
             __pos = __sz;
-        const_pointer __p = data();
-        for (const_pointer __ps = __p + __pos; __ps != __p;)
+        const value_type* __p = data();
+        for (const value_type* __ps = __p + __pos; __ps != __p;)
         {
             if (traits_type::eq(*--__ps, __c))
                 return static_cast<size_type>(__ps - __p);
@@ -3213,7 +3314,7 @@ basic_string<_CharT, _Traits, _Allocator>::rfind(value_type __c,
 
 template<class _CharT, class _Traits, class _Allocator>
 typename basic_string<_CharT, _Traits, _Allocator>::size_type
-basic_string<_CharT, _Traits, _Allocator>::find_first_of(const_pointer __s,
+basic_string<_CharT, _Traits, _Allocator>::find_first_of(const value_type* __s,
                                                          size_type __pos,
                                                          size_type __n) const _NOEXCEPT
 {
@@ -3223,8 +3324,8 @@ basic_string<_CharT, _Traits, _Allocator>::find_first_of(const_pointer __s,
     size_type __sz = size();
     if (__pos >= __sz || __n == 0)
         return npos;
-    const_pointer __p = data();
-    const_pointer __r = _VSTD::find_first_of(__p + __pos, __p + __sz, __s,
+    const value_type* __p = data();
+    const value_type* __r = _VSTD::find_first_of(__p + __pos, __p + __sz, __s,
                                             __s + __n, __traits_eq<traits_type>());
     if (__r == __p + __sz)
         return npos;
@@ -3243,7 +3344,7 @@ basic_string<_CharT, _Traits, _Allocator>::find_first_of(const basic_string& __s
 template<class _CharT, class _Traits, class _Allocator>
 _LIBCPP_INLINE_VISIBILITY inline
 typename basic_string<_CharT, _Traits, _Allocator>::size_type
-basic_string<_CharT, _Traits, _Allocator>::find_first_of(const_pointer __s,
+basic_string<_CharT, _Traits, _Allocator>::find_first_of(const value_type* __s,
                                                          size_type __pos) const _NOEXCEPT
 {
 #ifdef _LIBCPP_DEBUG
@@ -3265,7 +3366,7 @@ basic_string<_CharT, _Traits, _Allocator>::find_first_of(value_type __c,
 
 template<class _CharT, class _Traits, class _Allocator>
 typename basic_string<_CharT, _Traits, _Allocator>::size_type
-basic_string<_CharT, _Traits, _Allocator>::find_last_of(const_pointer __s,
+basic_string<_CharT, _Traits, _Allocator>::find_last_of(const value_type* __s,
                                                         size_type __pos,
                                                         size_type __n) const _NOEXCEPT
 {
@@ -3279,10 +3380,10 @@ basic_string<_CharT, _Traits, _Allocator>::find_last_of(const_pointer __s,
             ++__pos;
         else
             __pos = __sz;
-        const_pointer __p = data();
-        for (const_pointer __ps = __p + __pos; __ps != __p;)
+        const value_type* __p = data();
+        for (const value_type* __ps = __p + __pos; __ps != __p;)
         {
-            const_pointer __r = traits_type::find(__s, __n, *--__ps);
+            const value_type* __r = traits_type::find(__s, __n, *--__ps);
             if (__r)
                 return static_cast<size_type>(__ps - __p);
         }
@@ -3302,7 +3403,7 @@ basic_string<_CharT, _Traits, _Allocator>::find_last_of(const basic_string& __st
 template<class _CharT, class _Traits, class _Allocator>
 _LIBCPP_INLINE_VISIBILITY inline
 typename basic_string<_CharT, _Traits, _Allocator>::size_type
-basic_string<_CharT, _Traits, _Allocator>::find_last_of(const_pointer __s,
+basic_string<_CharT, _Traits, _Allocator>::find_last_of(const value_type* __s,
                                                         size_type __pos) const _NOEXCEPT
 {
 #ifdef _LIBCPP_DEBUG
@@ -3324,7 +3425,7 @@ basic_string<_CharT, _Traits, _Allocator>::find_last_of(value_type __c,
 
 template<class _CharT, class _Traits, class _Allocator>
 typename basic_string<_CharT, _Traits, _Allocator>::size_type
-basic_string<_CharT, _Traits, _Allocator>::find_first_not_of(const_pointer __s,
+basic_string<_CharT, _Traits, _Allocator>::find_first_not_of(const value_type* __s,
                                                              size_type __pos,
                                                              size_type __n) const _NOEXCEPT
 {
@@ -3334,9 +3435,9 @@ basic_string<_CharT, _Traits, _Allocator>::find_first_not_of(const_pointer __s,
     size_type __sz = size();
     if (__pos < __sz)
     {
-        const_pointer __p = data();
-        const_pointer __pe = __p + __sz;
-        for (const_pointer __ps = __p + __pos; __ps != __pe; ++__ps)
+        const value_type* __p = data();
+        const value_type* __pe = __p + __sz;
+        for (const value_type* __ps = __p + __pos; __ps != __pe; ++__ps)
             if (traits_type::find(__s, __n, *__ps) == 0)
                 return static_cast<size_type>(__ps - __p);
     }
@@ -3355,7 +3456,7 @@ basic_string<_CharT, _Traits, _Allocator>::find_first_not_of(const basic_string&
 template<class _CharT, class _Traits, class _Allocator>
 _LIBCPP_INLINE_VISIBILITY inline
 typename basic_string<_CharT, _Traits, _Allocator>::size_type
-basic_string<_CharT, _Traits, _Allocator>::find_first_not_of(const_pointer __s,
+basic_string<_CharT, _Traits, _Allocator>::find_first_not_of(const value_type* __s,
                                                              size_type __pos) const _NOEXCEPT
 {
 #ifdef _LIBCPP_DEBUG
@@ -3373,9 +3474,9 @@ basic_string<_CharT, _Traits, _Allocator>::find_first_not_of(value_type __c,
     size_type __sz = size();
     if (__pos < __sz)
     {
-        const_pointer __p = data();
-        const_pointer __pe = __p + __sz;
-        for (const_pointer __ps = __p + __pos; __ps != __pe; ++__ps)
+        const value_type* __p = data();
+        const value_type* __pe = __p + __sz;
+        for (const value_type* __ps = __p + __pos; __ps != __pe; ++__ps)
             if (!traits_type::eq(*__ps, __c))
                 return static_cast<size_type>(__ps - __p);
     }
@@ -3386,7 +3487,7 @@ basic_string<_CharT, _Traits, _Allocator>::find_first_not_of(value_type __c,
 
 template<class _CharT, class _Traits, class _Allocator>
 typename basic_string<_CharT, _Traits, _Allocator>::size_type
-basic_string<_CharT, _Traits, _Allocator>::find_last_not_of(const_pointer __s,
+basic_string<_CharT, _Traits, _Allocator>::find_last_not_of(const value_type* __s,
                                                             size_type __pos,
                                                             size_type __n) const _NOEXCEPT
 {
@@ -3398,8 +3499,8 @@ basic_string<_CharT, _Traits, _Allocator>::find_last_not_of(const_pointer __s,
         ++__pos;
     else
         __pos = __sz;
-    const_pointer __p = data();
-    for (const_pointer __ps = __p + __pos; __ps != __p;)
+    const value_type* __p = data();
+    for (const value_type* __ps = __p + __pos; __ps != __p;)
         if (traits_type::find(__s, __n, *--__ps) == 0)
             return static_cast<size_type>(__ps - __p);
     return npos;
@@ -3417,7 +3518,7 @@ basic_string<_CharT, _Traits, _Allocator>::find_last_not_of(const basic_string&
 template<class _CharT, class _Traits, class _Allocator>
 _LIBCPP_INLINE_VISIBILITY inline
 typename basic_string<_CharT, _Traits, _Allocator>::size_type
-basic_string<_CharT, _Traits, _Allocator>::find_last_not_of(const_pointer __s,
+basic_string<_CharT, _Traits, _Allocator>::find_last_not_of(const value_type* __s,
                                                             size_type __pos) const _NOEXCEPT
 {
 #ifdef _LIBCPP_DEBUG
@@ -3437,8 +3538,8 @@ basic_string<_CharT, _Traits, _Allocator>::find_last_not_of(value_type __c,
         ++__pos;
     else
         __pos = __sz;
-    const_pointer __p = data();
-    for (const_pointer __ps = __p + __pos; __ps != __p;)
+    const value_type* __p = data();
+    for (const value_type* __ps = __p + __pos; __ps != __p;)
         if (!traits_type::eq(*--__ps, __c))
             return static_cast<size_type>(__ps - __p);
     return npos;
@@ -3491,7 +3592,7 @@ basic_string<_CharT, _Traits, _Allocator>::compare(size_type __pos1,
 
 template <class _CharT, class _Traits, class _Allocator>
 int
-basic_string<_CharT, _Traits, _Allocator>::compare(const_pointer __s) const _NOEXCEPT
+basic_string<_CharT, _Traits, _Allocator>::compare(const value_type* __s) const _NOEXCEPT
 {
 #ifdef _LIBCPP_DEBUG
     assert(__s != 0);
@@ -3503,7 +3604,7 @@ template <class _CharT, class _Traits, class _Allocator>
 int
 basic_string<_CharT, _Traits, _Allocator>::compare(size_type __pos1,
                                                    size_type __n1,
-                                                   const_pointer __s) const
+                                                   const value_type* __s) const
 {
 #ifdef _LIBCPP_DEBUG
     assert(__s != 0);
@@ -3515,7 +3616,7 @@ template <class _CharT, class _Traits, class _Allocator>
 int
 basic_string<_CharT, _Traits, _Allocator>::compare(size_type __pos1,
                                                    size_type __n1,
-                                                   const_pointer __s,
+                                                   const value_type* __s,
                                                    size_type __n2) const
 {
 #ifdef _LIBCPP_DEBUG
diff --git a/include/type_traits b/include/type_traits
index ab0e22201627..450b5928eff2 100644
--- a/include/type_traits
+++ b/include/type_traits
@@ -137,6 +137,64 @@ namespace std
     template <class> class result_of; // undefined
     template <class Fn, class... ArgTypes> class result_of<Fn(ArgTypes...)>;
 
+    // const-volatile modifications:
+    template <class T>
+      using remove_const_t    = typename remove_const<T>::type;  // C++14
+    template <class T>
+      using remove_volatile_t = typename remove_volatile<T>::type;  // C++14
+    template <class T>
+      using remove_cv_t       = typename remove_cv<T>::type;  // C++14
+    template <class T>
+      using add_const_t       = typename add_const<T>::type;  // C++14
+    template <class T>
+      using add_volatile_t    = typename add_volatile<T>::type;  // C++14
+    template <class T>
+      using add_cv_t          = typename add_cv<T>::type;  // C++14
+  
+    // reference modifications:
+    template <class T>
+      using remove_reference_t     = typename remove_reference<T>::type;  // C++14
+    template <class T>
+      using add_lvalue_reference_t = typename add_lvalue_reference<T>::type;  // C++14
+    template <class T>
+      using add_rvalue_reference_t = typename add_rvalue_reference<T>::type;  // C++14
+  
+    // sign modifications:
+    template <class T>
+      using make_signed_t   = typename make_signed<T>::type;  // C++14
+    template <class T>
+      using make_unsigned_t = typename make_unsigned<T>::type;  // C++14
+  
+    // array modifications:
+    template <class T>
+      using remove_extent_t      = typename remove_extent<T>::type;  // C++14
+    template <class T>
+      using remove_all_extents_t = typename remove_all_extents<T>::type;  // C++14
+
+    // pointer modifications:
+    template <class T>
+      using remove_pointer_t = typename remove_pointer<T>::type;  // C++14
+    template <class T>
+      using add_pointer_t    = typename add_pointer<T>::type;  // C++14
+
+    // other transformations:
+    template <size_t Len, std::size_t Align=default-alignment>
+      using aligned_storage_t = typename aligned_storage<Len,Align>::type;  // C++14
+    template <std::size_t Len, class... Types>
+      using aligned_union_t   = typename aligned_union<Len,Types...>::type;  // C++14
+    template <class T>
+      using decay_t           = typename decay<T>::type;  // C++14
+    template <bool b, class T=void>
+      using enable_if_t       = typename enable_if<b,T>::type;  // C++14
+    template <bool b, class T, class F>
+      using conditional_t     = typename conditional<b,T,F>::type;  // C++14
+    template <class... T>
+      using common_type_t     = typename common_type<T...>::type;  // C++14
+    template <class T>
+      using underlying_type_t = typename underlying_type<T>::type;  // C++14
+    template <class F, class... ArgTypes>
+      using result_of_t       = typename result_of<F(ArgTypes...)>::type;  // C++14
+
 }  // std
 
 */
@@ -154,9 +212,18 @@ template <bool _Bp, class _If, class _Then>
 template <class _If, class _Then>
     struct _LIBCPP_TYPE_VIS conditional<false, _If, _Then> {typedef _Then type;};
 
+#if _LIBCPP_STD_VER > 11
+template <bool _Bp, class _If, class _Then> using conditional_t = typename conditional<_Bp, _If, _Then>::type;
+#endif
+
 template <bool, class _Tp = void> struct _LIBCPP_TYPE_VIS enable_if {};
 template <class _Tp> struct _LIBCPP_TYPE_VIS enable_if<true, _Tp> {typedef _Tp type;};
 
+#if _LIBCPP_STD_VER > 11
+template <bool _Bp, class _Tp = void> using enable_if_t = typename enable_if<_Bp, _Tp>::type;
+#endif
+
+
 struct __two {char __lx[2];};
 
 // helper class:
@@ -191,16 +258,25 @@ template <class _Tp> struct _LIBCPP_TYPE_VIS is_volatile<_Tp volatile> : public
 
 template <class _Tp> struct _LIBCPP_TYPE_VIS remove_const            {typedef _Tp type;};
 template <class _Tp> struct _LIBCPP_TYPE_VIS remove_const<const _Tp> {typedef _Tp type;};
+#if _LIBCPP_STD_VER > 11
+template <class _Tp> using remove_const_t = typename remove_const<_Tp>::type;
+#endif
 
 // remove_volatile
 
 template <class _Tp> struct _LIBCPP_TYPE_VIS remove_volatile               {typedef _Tp type;};
 template <class _Tp> struct _LIBCPP_TYPE_VIS remove_volatile<volatile _Tp> {typedef _Tp type;};
+#if _LIBCPP_STD_VER > 11
+template <class _Tp> using remove_volatile_t = typename remove_volatile<_Tp>::type;
+#endif
 
 // remove_cv
 
 template <class _Tp> struct _LIBCPP_TYPE_VIS remove_cv
 {typedef typename remove_volatile<typename remove_const<_Tp>::type>::type type;};
+#if _LIBCPP_STD_VER > 11
+template <class _Tp> using remove_cv_t = typename remove_cv<_Tp>::type;
+#endif
 
 // is_void
 
@@ -446,6 +522,10 @@ struct __add_const<_Tp, false> {typedef const _Tp type;};
 template <class _Tp> struct _LIBCPP_TYPE_VIS add_const
     {typedef typename __add_const<_Tp>::type type;};
 
+#if _LIBCPP_STD_VER > 11
+template <class _Tp> using add_const_t = typename add_const<_Tp>::type;
+#endif
+
 // add_volatile
 
 template <class _Tp, bool = is_reference<_Tp>::value ||
@@ -459,11 +539,19 @@ struct __add_volatile<_Tp, false> {typedef volatile _Tp type;};
 template <class _Tp> struct _LIBCPP_TYPE_VIS add_volatile
     {typedef typename __add_volatile<_Tp>::type type;};
 
+#if _LIBCPP_STD_VER > 11
+template <class _Tp> using add_volatile_t = typename add_volatile<_Tp>::type;
+#endif
+
 // add_cv
 
 template <class _Tp> struct _LIBCPP_TYPE_VIS add_cv
     {typedef typename add_const<typename add_volatile<_Tp>::type>::type type;};
 
+#if _LIBCPP_STD_VER > 11
+template <class _Tp> using add_cv_t = typename add_cv<_Tp>::type;
+#endif
+
 // remove_reference
 
 template <class _Tp> struct _LIBCPP_TYPE_VIS remove_reference        {typedef _Tp type;};
@@ -472,6 +560,10 @@ template <class _Tp> struct _LIBCPP_TYPE_VIS remove_reference<_Tp&>  {typedef _T
 template <class _Tp> struct _LIBCPP_TYPE_VIS remove_reference<_Tp&&> {typedef _Tp type;};
 #endif
 
+#if _LIBCPP_STD_VER > 11
+template <class _Tp> using remove_reference_t = typename remove_reference<_Tp>::type;
+#endif
+
 // add_lvalue_reference
 
 template <class _Tp> struct _LIBCPP_TYPE_VIS add_lvalue_reference                      {typedef _Tp& type;};
@@ -481,6 +573,10 @@ template <>          struct _LIBCPP_TYPE_VIS add_lvalue_reference<const void>
 template <>          struct _LIBCPP_TYPE_VIS add_lvalue_reference<volatile void>       {typedef volatile void type;};
 template <>          struct _LIBCPP_TYPE_VIS add_lvalue_reference<const volatile void> {typedef const volatile void type;};
 
+#if _LIBCPP_STD_VER > 11
+template <class _Tp> using add_lvalue_reference_t = typename add_lvalue_reference<_Tp>::type;
+#endif
+
 #ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES
 
 template <class _Tp> struct _LIBCPP_TYPE_VIS  add_rvalue_reference                     {typedef _Tp&& type;};
@@ -489,6 +585,10 @@ template <>          struct _LIBCPP_TYPE_VIS add_rvalue_reference<const void>
 template <>          struct _LIBCPP_TYPE_VIS add_rvalue_reference<volatile void>       {typedef volatile void type;};
 template <>          struct _LIBCPP_TYPE_VIS add_rvalue_reference<const volatile void> {typedef const volatile void type;};
 
+#if _LIBCPP_STD_VER > 11
+template <class _Tp> using add_rvalue_reference_t = typename add_rvalue_reference<_Tp>::type;
+#endif
+
 #endif  // _LIBCPP_HAS_NO_RVALUE_REFERENCES
 
 #ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES
@@ -518,11 +618,19 @@ template <class _Tp> struct _LIBCPP_TYPE_VIS remove_pointer<_Tp* const>
 template <class _Tp> struct _LIBCPP_TYPE_VIS remove_pointer<_Tp* volatile>       {typedef _Tp type;};
 template <class _Tp> struct _LIBCPP_TYPE_VIS remove_pointer<_Tp* const volatile> {typedef _Tp type;};
 
+#if _LIBCPP_STD_VER > 11
+template <class _Tp> using remove_pointer_t = typename remove_pointer<_Tp>::type;
+#endif
+
 // add_pointer
 
 template <class _Tp> struct _LIBCPP_TYPE_VIS add_pointer
     {typedef typename remove_reference<_Tp>::type* type;};
 
+#if _LIBCPP_STD_VER > 11
+template <class _Tp> using add_pointer_t = typename add_pointer<_Tp>::type;
+#endif
+
 // is_signed
 
 template <class _Tp, bool = is_integral<_Tp>::value>
@@ -584,6 +692,10 @@ template <class _Tp> struct _LIBCPP_TYPE_VIS remove_extent<_Tp[]>
 template <class _Tp, size_t _Np> struct _LIBCPP_TYPE_VIS remove_extent<_Tp[_Np]>
     {typedef _Tp type;};
 
+#if _LIBCPP_STD_VER > 11
+template <class _Tp> using remove_extent_t = typename remove_extent<_Tp>::type;
+#endif
+
 // remove_all_extents
 
 template <class _Tp> struct _LIBCPP_TYPE_VIS remove_all_extents
@@ -593,6 +705,10 @@ template <class _Tp> struct _LIBCPP_TYPE_VIS remove_all_extents<_Tp[]>
 template <class _Tp, size_t _Np> struct _LIBCPP_TYPE_VIS remove_all_extents<_Tp[_Np]>
     {typedef typename remove_all_extents<_Tp>::type type;};
 
+#if _LIBCPP_STD_VER > 11
+template <class _Tp> using remove_all_extents_t = typename remove_all_extents<_Tp>::type;
+#endif
+
 // is_abstract
 
 namespace __is_abstract_imp
@@ -916,7 +1032,7 @@ template <class _Hp, class _Tp, size_t _Len>
 struct __find_max_align<__type_list<_Hp, _Tp>, _Len>
     : public integral_constant<size_t, __select_align<_Len, _Hp::value, __find_max_align<_Tp, _Len>::value>::value> {};
 
-template <size_t _Len, const size_t _Align = __find_max_align<__all_types, _Len>::value>
+template <size_t _Len, size_t _Align = __find_max_align<__all_types, _Len>::value>
 struct _LIBCPP_TYPE_VIS aligned_storage
 {
     typedef typename __find_pod<__all_types, _Align>::type _Aligner;
@@ -928,6 +1044,11 @@ struct _LIBCPP_TYPE_VIS aligned_storage
     };
 };
 
+#if _LIBCPP_STD_VER > 11
+template <size_t _Len, size_t _Align = __find_max_align<__all_types, _Len>::value>
+    using aligned_storage_t = typename aligned_storage<_Len, _Align>::type;
+#endif
+
 #define _CREATE_ALIGNED_STORAGE_SPECIALIZATION(n) \
 template <size_t _Len>\
 struct _LIBCPP_TYPE_VIS aligned_storage<_Len, n>\
@@ -989,6 +1110,10 @@ struct aligned_union
     typedef typename aligned_storage<__len, alignment_value>::type type;
 };
 
+#if _LIBCPP_STD_VER > 11
+template <size_t _Len, class ..._Types> using aligned_union_t = typename aligned_union<_Len, _Types...>::type;
+#endif
+
 #endif  // _LIBCPP_HAS_NO_VARIADICS
 
 // __promote
@@ -1150,6 +1275,10 @@ struct _LIBCPP_TYPE_VIS make_signed
     typedef typename __apply_cv<_Tp, typename __make_signed<typename remove_cv<_Tp>::type>::type>::type type;
 };
 
+#if _LIBCPP_STD_VER > 11
+template <class _Tp> using make_signed_t = typename make_signed<_Tp>::type;
+#endif
+
 template <class _Tp, bool = is_integral<_Tp>::value || is_enum<_Tp>::value>
 struct __make_unsigned {};
 
@@ -1175,6 +1304,10 @@ struct _LIBCPP_TYPE_VIS make_unsigned
     typedef typename __apply_cv<_Tp, typename __make_unsigned<typename remove_cv<_Tp>::type>::type>::type type;
 };
 
+#if _LIBCPP_STD_VER > 11
+template <class _Tp> using make_unsigned_t = typename make_unsigned<_Tp>::type;
+#endif
+
 #ifdef _LIBCPP_HAS_NO_VARIADICS
 
 template <class _Tp, class _Up = void, class V = void>
@@ -1233,6 +1366,10 @@ struct _LIBCPP_TYPE_VIS common_type<_Tp, _Up, _Vp...>
     typedef typename common_type<typename common_type<_Tp, _Up>::type, _Vp...>::type type;
 };
 
+#if _LIBCPP_STD_VER > 11
+template <class ..._Tp> using common_type_t = typename common_type<_Tp...>::type;
+#endif
+
 #endif  // _LIBCPP_HAS_NO_VARIADICS
 
 // is_assignable
@@ -1411,6 +1548,10 @@ public:
                      >::type type;
 };
 
+#if _LIBCPP_STD_VER > 11
+template <class _Tp> using decay_t = typename decay<_Tp>::type;
+#endif
+
 #ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES
 
 template <class _Tp>
@@ -1653,7 +1794,7 @@ struct __member_pointer_traits_imp<_Rp _Class::*, false, true>
 
 template <class _MP>
 struct __member_pointer_traits
-    : public __member_pointer_traits_imp<_MP,
+    : public __member_pointer_traits_imp<typename remove_cv<_MP>::type,
                     is_member_function_pointer<_MP>::value,
                     is_member_object_pointer<_MP>::value>
 {
@@ -2878,13 +3019,27 @@ __invoke(__any, _Args&& ...__args)
 
 // bullets 1 and 2
 
-template <class _Fp, class _A0, class ..._Args>
+template <class _Fp, class _A0, class ..._Args,
+            class = typename enable_if
+            <
+                is_member_function_pointer<typename remove_reference<_Fp>::type>::value &&
+                is_base_of<typename __member_pointer_traits<typename remove_reference<_Fp>::type>::_ClassType,
+                           typename remove_reference<_A0>::type>::value
+            >::type
+         >
 _LIBCPP_INLINE_VISIBILITY
 auto
 __invoke(_Fp&& __f, _A0&& __a0, _Args&& ...__args)
     -> decltype((_VSTD::forward<_A0>(__a0).*__f)(_VSTD::forward<_Args>(__args)...));
 
-template <class _Fp, class _A0, class ..._Args>
+template <class _Fp, class _A0, class ..._Args,
+            class = typename enable_if
+            <
+                is_member_function_pointer<typename remove_reference<_Fp>::type>::value &&
+                !is_base_of<typename __member_pointer_traits<typename remove_reference<_Fp>::type>::_ClassType,
+                           typename remove_reference<_A0>::type>::value
+            >::type
+         >
 _LIBCPP_INLINE_VISIBILITY
 auto
 __invoke(_Fp&& __f, _A0&& __a0, _Args&& ...__args)
@@ -2892,13 +3047,27 @@ __invoke(_Fp&& __f, _A0&& __a0, _Args&& ...__args)
 
 // bullets 3 and 4
 
-template <class _Fp, class _A0>
+template <class _Fp, class _A0,
+            class = typename enable_if
+            <
+                is_member_object_pointer<typename remove_reference<_Fp>::type>::value &&
+                is_base_of<typename __member_pointer_traits<typename remove_reference<_Fp>::type>::_ClassType,
+                           typename remove_reference<_A0>::type>::value
+            >::type
+         >
 _LIBCPP_INLINE_VISIBILITY
 auto
 __invoke(_Fp&& __f, _A0&& __a0)
     -> decltype(_VSTD::forward<_A0>(__a0).*__f);
 
-template <class _Fp, class _A0>
+template <class _Fp, class _A0,
+            class = typename enable_if
+            <
+                is_member_object_pointer<typename remove_reference<_Fp>::type>::value &&
+                !is_base_of<typename __member_pointer_traits<typename remove_reference<_Fp>::type>::_ClassType,
+                           typename remove_reference<_A0>::type>::value
+            >::type
+         >
 _LIBCPP_INLINE_VISIBILITY
 auto
 __invoke(_Fp&& __f, _A0&& __a0)
@@ -2956,6 +3125,10 @@ class _LIBCPP_TYPE_VIS result_of<_Fp(_Args...)>
 {
 };
 
+#if _LIBCPP_STD_VER > 11
+template <class _Tp> using result_of_t = typename result_of<_Tp>::type;
+#endif
+
 #endif  // _LIBCPP_HAS_NO_VARIADICS
 
 template <class _Tp>
@@ -3050,6 +3223,10 @@ struct underlying_type
     typedef _LIBCXX_UNDERLYING_TYPE(_Tp) type;
 };
 
+#if _LIBCPP_STD_VER > 11
+template <class _Tp> using underlying_type_t = typename underlying_type<_Tp>::type;
+#endif
+
 #else  // _LIBCXX_UNDERLYING_TYPE
 
 template <class _Tp, bool _Support = false>
diff --git a/include/unordered_map b/include/unordered_map
index 235b2eabb603..78e630757b47 100644
--- a/include/unordered_map
+++ b/include/unordered_map
@@ -325,7 +325,7 @@ template <class Key, class T, class Hash, class Pred, class Alloc>
 
 _LIBCPP_BEGIN_NAMESPACE_STD
 
-template <class _Key, class _Tp, class _Hash, bool = is_empty<_Hash>::value
+template <class _Key, class _Cp, class _Hash, bool = is_empty<_Hash>::value
 #if __has_feature(is_final)
                                          && !__is_final(_Hash)
 #endif
@@ -333,8 +333,6 @@ template <class _Key, class _Tp, class _Hash, bool = is_empty<_Hash>::value
 class __unordered_map_hasher
     : private _Hash
 {
-    typedef pair<typename remove_const<_Key>::type, _Tp> _Pp;
-    typedef pair<const _Key, _Tp> _Cp;
 public:
     _LIBCPP_INLINE_VISIBILITY
     __unordered_map_hasher()
@@ -347,23 +345,18 @@ public:
     _LIBCPP_INLINE_VISIBILITY
     const _Hash& hash_function() const _NOEXCEPT {return *this;}
     _LIBCPP_INLINE_VISIBILITY
-    size_t operator()(const _Pp& __x) const
-        {return static_cast<const _Hash&>(*this)(__x.first);}
-    _LIBCPP_INLINE_VISIBILITY
     size_t operator()(const _Cp& __x) const
-        {return static_cast<const _Hash&>(*this)(__x.first);}
+        {return static_cast<const _Hash&>(*this)(__x.__cc.first);}
     _LIBCPP_INLINE_VISIBILITY
     size_t operator()(const _Key& __x) const
         {return static_cast<const _Hash&>(*this)(__x);}
 };
 
-template <class _Key, class _Tp, class _Hash>
-class __unordered_map_hasher<_Key, _Tp, _Hash, false>
+template <class _Key, class _Cp, class _Hash>
+class __unordered_map_hasher<_Key, _Cp, _Hash, false>
 {
     _Hash __hash_;
 
-    typedef pair<typename remove_const<_Key>::type, _Tp> _Pp;
-    typedef pair<const _Key, _Tp> _Cp;
 public:
     _LIBCPP_INLINE_VISIBILITY
     __unordered_map_hasher()
@@ -376,17 +369,14 @@ public:
     _LIBCPP_INLINE_VISIBILITY
     const _Hash& hash_function() const _NOEXCEPT {return __hash_;}
     _LIBCPP_INLINE_VISIBILITY
-    size_t operator()(const _Pp& __x) const
-        {return __hash_(__x.first);}
-    _LIBCPP_INLINE_VISIBILITY
     size_t operator()(const _Cp& __x) const
-        {return __hash_(__x.first);}
+        {return __hash_(__x.__cc.first);}
     _LIBCPP_INLINE_VISIBILITY
     size_t operator()(const _Key& __x) const
         {return __hash_(__x);}
 };
 
-template <class _Key, class _Tp, class _Pred, bool = is_empty<_Pred>::value
+template <class _Key, class _Cp, class _Pred, bool = is_empty<_Pred>::value
 #if __has_feature(is_final)
                                          && !__is_final(_Pred)
 #endif
@@ -394,8 +384,6 @@ template <class _Key, class _Tp, class _Pred, bool = is_empty<_Pred>::value
 class __unordered_map_equal
     : private _Pred
 {
-    typedef pair<typename remove_const<_Key>::type, _Tp> _Pp;
-    typedef pair<const _Key, _Tp> _Cp;
 public:
     _LIBCPP_INLINE_VISIBILITY
     __unordered_map_equal()
@@ -408,41 +396,21 @@ public:
     _LIBCPP_INLINE_VISIBILITY
     const _Pred& key_eq() const _NOEXCEPT {return *this;}
     _LIBCPP_INLINE_VISIBILITY
-    bool operator()(const _Pp& __x, const _Pp& __y) const
-        {return static_cast<const _Pred&>(*this)(__x.first, __y.first);}
-    _LIBCPP_INLINE_VISIBILITY
-    bool operator()(const _Pp& __x, const _Cp& __y) const
-        {return static_cast<const _Pred&>(*this)(__x.first, __y.first);}
-    _LIBCPP_INLINE_VISIBILITY
-    bool operator()(const _Pp& __x, const _Key& __y) const
-        {return static_cast<const _Pred&>(*this)(__x.first, __y);}
-    _LIBCPP_INLINE_VISIBILITY
-    bool operator()(const _Cp& __x, const _Pp& __y) const
-        {return static_cast<const _Pred&>(*this)(__x.first, __y.first);}
-    _LIBCPP_INLINE_VISIBILITY
     bool operator()(const _Cp& __x, const _Cp& __y) const
-        {return static_cast<const _Pred&>(*this)(__x.first, __y.first);}
+        {return static_cast<const _Pred&>(*this)(__x.__cc.first, __y.__cc.first);}
     _LIBCPP_INLINE_VISIBILITY
     bool operator()(const _Cp& __x, const _Key& __y) const
-        {return static_cast<const _Pred&>(*this)(__x.first, __y);}
-    _LIBCPP_INLINE_VISIBILITY
-    bool operator()(const _Key& __x, const _Pp& __y) const
-        {return static_cast<const _Pred&>(*this)(__x, __y.first);}
+        {return static_cast<const _Pred&>(*this)(__x.__cc.first, __y);}
     _LIBCPP_INLINE_VISIBILITY
     bool operator()(const _Key& __x, const _Cp& __y) const
-        {return static_cast<const _Pred&>(*this)(__x, __y.first);}
-    _LIBCPP_INLINE_VISIBILITY
-    bool operator()(const _Key& __x, const _Key& __y) const
-        {return static_cast<const _Pred&>(*this)(__x, __y);}
+        {return static_cast<const _Pred&>(*this)(__x, __y.__cc.first);}
 };
 
-template <class _Key, class _Tp, class _Pred>
-class __unordered_map_equal<_Key, _Tp, _Pred, false>
+template <class _Key, class _Cp, class _Pred>
+class __unordered_map_equal<_Key, _Cp, _Pred, false>
 {
     _Pred __pred_;
 
-    typedef pair<typename remove_const<_Key>::type, _Tp> _Pp;
-    typedef pair<const _Key, _Tp> _Cp;
 public:
     _LIBCPP_INLINE_VISIBILITY
     __unordered_map_equal()
@@ -455,32 +423,14 @@ public:
     _LIBCPP_INLINE_VISIBILITY
     const _Pred& key_eq() const _NOEXCEPT {return __pred_;}
     _LIBCPP_INLINE_VISIBILITY
-    bool operator()(const _Pp& __x, const _Pp& __y) const
-        {return __pred_(__x.first, __y.first);}
-    _LIBCPP_INLINE_VISIBILITY
-    bool operator()(const _Pp& __x, const _Cp& __y) const
-        {return __pred_(__x.first, __y.first);}
-    _LIBCPP_INLINE_VISIBILITY
-    bool operator()(const _Pp& __x, const _Key& __y) const
-        {return __pred_(__x.first, __y);}
-    _LIBCPP_INLINE_VISIBILITY
-    bool operator()(const _Cp& __x, const _Pp& __y) const
-        {return __pred_(__x.first, __y.first);}
-    _LIBCPP_INLINE_VISIBILITY
     bool operator()(const _Cp& __x, const _Cp& __y) const
-        {return __pred_(__x.first, __y.first);}
+        {return __pred_(__x.__cc.first, __y.__cc.first);}
     _LIBCPP_INLINE_VISIBILITY
     bool operator()(const _Cp& __x, const _Key& __y) const
-        {return __pred_(__x.first, __y);}
-    _LIBCPP_INLINE_VISIBILITY
-    bool operator()(const _Key& __x, const _Pp& __y) const
-        {return __pred_(__x, __y.first);}
+        {return __pred_(__x.__cc.first, __y);}
     _LIBCPP_INLINE_VISIBILITY
     bool operator()(const _Key& __x, const _Cp& __y) const
-        {return __pred_(__x, __y.first);}
-    _LIBCPP_INLINE_VISIBILITY
-    bool operator()(const _Key& __x, const _Key& __y) const
-        {return __pred_(__x, __y);}
+        {return __pred_(__x, __y.__cc.first);}
 };
 
 template <class _Alloc>
@@ -492,8 +442,8 @@ class __hash_map_node_destructor
 public:
     typedef typename __alloc_traits::pointer    pointer;
 private:
-    typedef typename value_type::first_type     first_type;
-    typedef typename value_type::second_type    second_type;
+    typedef typename value_type::value_type::first_type     first_type;
+    typedef typename value_type::value_type::second_type    second_type;
 
     allocator_type& __na_;
 
@@ -535,9 +485,9 @@ public:
     void operator()(pointer __p) _NOEXCEPT
     {
         if (__second_constructed)
-            __alloc_traits::destroy(__na_, _VSTD::addressof(__p->__value_.second));
+            __alloc_traits::destroy(__na_, _VSTD::addressof(__p->__value_.__cc.second));
         if (__first_constructed)
-            __alloc_traits::destroy(__na_, _VSTD::addressof(__p->__value_.first));
+            __alloc_traits::destroy(__na_, _VSTD::addressof(__p->__value_.__cc.first));
         if (__p)
             __alloc_traits::deallocate(__na_, __p, 1);
     }
@@ -549,8 +499,8 @@ class _LIBCPP_TYPE_VIS __hash_map_iterator
     _HashIterator __i_;
 
     typedef pointer_traits<typename _HashIterator::pointer>      __pointer_traits;
-    typedef const typename _HashIterator::value_type::first_type key_type;
-    typedef typename _HashIterator::value_type::second_type      mapped_type;
+    typedef const typename _HashIterator::value_type::value_type::first_type key_type;
+    typedef typename _HashIterator::value_type::value_type::second_type      mapped_type;
 public:
     typedef forward_iterator_tag                                 iterator_category;
     typedef pair<key_type, mapped_type>                          value_type;
@@ -571,9 +521,9 @@ public:
     __hash_map_iterator(_HashIterator __i) _NOEXCEPT : __i_(__i) {}
 
     _LIBCPP_INLINE_VISIBILITY
-    reference operator*() const {return *operator->();}
+    reference operator*() const {return __i_->__cc;}
     _LIBCPP_INLINE_VISIBILITY
-    pointer operator->() const {return (pointer)__i_.operator->();}
+    pointer operator->() const {return pointer_traits<pointer>::pointer_to(__i_->__cc);}
 
     _LIBCPP_INLINE_VISIBILITY
     __hash_map_iterator& operator++() {++__i_; return *this;}
@@ -605,8 +555,8 @@ class _LIBCPP_TYPE_VIS __hash_map_const_iterator
     _HashIterator __i_;
 
     typedef pointer_traits<typename _HashIterator::pointer>      __pointer_traits;
-    typedef const typename _HashIterator::value_type::first_type key_type;
-    typedef typename _HashIterator::value_type::second_type      mapped_type;
+    typedef const typename _HashIterator::value_type::value_type::first_type key_type;
+    typedef typename _HashIterator::value_type::value_type::second_type      mapped_type;
 public:
     typedef forward_iterator_tag                                 iterator_category;
     typedef pair<key_type, mapped_type>                          value_type;
@@ -632,9 +582,9 @@ public:
                 : __i_(__i.__i_) {}
 
     _LIBCPP_INLINE_VISIBILITY
-    reference operator*() const {return *operator->();}
+    reference operator*() const {return __i_->__cc;}
     _LIBCPP_INLINE_VISIBILITY
-    pointer operator->() const {return (pointer)__i_.operator->();}
+    pointer operator->() const {return pointer_traits<pointer>::pointer_to(__i_->__cc);}
 
     _LIBCPP_INLINE_VISIBILITY
     __hash_map_const_iterator& operator++() {++__i_; return *this;}
@@ -671,13 +621,56 @@ public:
     typedef _Pred                                          key_equal;
     typedef _Alloc                                         allocator_type;
     typedef pair<const key_type, mapped_type>              value_type;
+    typedef pair<key_type, mapped_type>                    __nc_value_type;
     typedef value_type&                                    reference;
     typedef const value_type&                              const_reference;
 
 private:
-    typedef pair<key_type, mapped_type>                    __value_type;
-    typedef __unordered_map_hasher<key_type, mapped_type, hasher>   __hasher;
-    typedef __unordered_map_equal<key_type, mapped_type, key_equal> __key_equal;
+#if __cplusplus >= 201103L
+    union __value_type
+    {
+        typedef typename unordered_map::value_type value_type;
+        typedef typename unordered_map::__nc_value_type __nc_value_type;
+        value_type __cc;
+        __nc_value_type __nc;
+
+        template <class ..._Args>
+        __value_type(_Args&& ...__args)
+            : __cc(std::forward<_Args>(__args)...) {}
+
+        __value_type(const __value_type& __v)
+            : __cc(std::move(__v.__cc)) {}
+
+        __value_type(__value_type&& __v)
+            : __nc(std::move(__v.__nc)) {}
+
+        __value_type& operator=(const __value_type& __v)
+            {__nc = __v.__cc; return *this;}
+
+        __value_type& operator=(__value_type&& __v)
+            {__nc = std::move(__v.__nc); return *this;}
+
+        ~__value_type() {__cc.~value_type();}
+    };
+#else
+    struct __value_type
+    {
+        typedef typename unordered_map::value_type value_type;
+        value_type __cc;
+
+        __value_type() {}
+
+        template <class _A0>
+        __value_type(const _A0& __a0)
+            : __cc(__a0) {}
+
+        template <class _A0, class _A1>
+        __value_type(const _A0& __a0, const _A1& __a1)
+            : __cc(__a0, __a1) {}
+    };
+#endif
+    typedef __unordered_map_hasher<key_type, __value_type, hasher>   __hasher;
+    typedef __unordered_map_equal<key_type, __value_type, key_equal> __key_equal;
     typedef typename allocator_traits<allocator_type>::template
 #ifndef _LIBCPP_HAS_NO_TEMPLATE_ALIASES
             rebind_alloc<__value_type>
@@ -750,7 +743,16 @@ public:
     _LIBCPP_INLINE_VISIBILITY
     unordered_map& operator=(const unordered_map& __u)
     {
+#if __cplusplus >= 201103L
         __table_ = __u.__table_;
+#else
+        __table_.clear();
+        __table_.hash_function() = __u.__table_.hash_function();
+        __table_.key_eq() = __u.__table_.key_eq();
+        __table_.max_load_factor() = __u.__table_.max_load_factor();
+        __table_.__copy_assign_alloc(__u.__table_);
+        insert(__u.begin(), __u.end());
+#endif
         return *this;
     }
 #ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES
@@ -907,26 +909,15 @@ private:
 #ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES
     __node_holder __construct_node();
     template <class _A0>
-        typename enable_if
-        <
-            is_constructible<value_type, _A0>::value,
-            __node_holder
-        >::type
-         __construct_node(_A0&& __a0);
-    template <class _A0>
-        typename enable_if
-        <
-            is_constructible<key_type, _A0>::value,
-            __node_holder
-        >::type
+        __node_holder
          __construct_node(_A0&& __a0);
+    __node_holder __construct_node_with_key(key_type&& __k);
 #ifndef _LIBCPP_HAS_NO_VARIADICS
     template <class _A0, class _A1, class ..._Args>
         __node_holder __construct_node(_A0&& __a0, _A1&& __a1, _Args&& ...__args);
 #endif  // _LIBCPP_HAS_NO_VARIADICS
-#else  // _LIBCPP_HAS_NO_RVALUE_REFERENCES
-    __node_holder __construct_node(const key_type& __k);
-#endif
+#endif  // _LIBCPP_HAS_NO_RVALUE_REFERENCES
+    __node_holder __construct_node_with_key(const key_type& __k);
 };
 
 template <class _Key, class _Tp, class _Hash, class _Pred, class _Alloc>
@@ -1105,11 +1096,7 @@ unordered_map<_Key, _Tp, _Hash, _Pred, _Alloc>::__construct_node()
 
 template <class _Key, class _Tp, class _Hash, class _Pred, class _Alloc>
 template <class _A0>
-typename enable_if
-<
-    is_constructible<pair<const _Key, _Tp>, _A0>::value,
-    typename unordered_map<_Key, _Tp, _Hash, _Pred, _Alloc>::__node_holder
->::type
+typename unordered_map<_Key, _Tp, _Hash, _Pred, _Alloc>::__node_holder
 unordered_map<_Key, _Tp, _Hash, _Pred, _Alloc>::__construct_node(_A0&& __a0)
 {
     __node_allocator& __na = __table_.__node_alloc();
@@ -1122,22 +1109,16 @@ unordered_map<_Key, _Tp, _Hash, _Pred, _Alloc>::__construct_node(_A0&& __a0)
 }
 
 template <class _Key, class _Tp, class _Hash, class _Pred, class _Alloc>
-template <class _A0>
-typename enable_if
-<
-    is_constructible<_Key, _A0>::value,
-    typename unordered_map<_Key, _Tp, _Hash, _Pred, _Alloc>::__node_holder
->::type
-unordered_map<_Key, _Tp, _Hash, _Pred, _Alloc>::__construct_node(_A0&& __a0)
+typename unordered_map<_Key, _Tp, _Hash, _Pred, _Alloc>::__node_holder
+unordered_map<_Key, _Tp, _Hash, _Pred, _Alloc>::__construct_node_with_key(key_type&& __k)
 {
     __node_allocator& __na = __table_.__node_alloc();
     __node_holder __h(__node_traits::allocate(__na, 1), _Dp(__na));
-    __node_traits::construct(__na, _VSTD::addressof(__h->__value_.first),
-                             _VSTD::forward<_A0>(__a0));
+    __node_traits::construct(__na, _VSTD::addressof(__h->__value_.__cc.first), _VSTD::move(__k));
     __h.get_deleter().__first_constructed = true;
-    __node_traits::construct(__na, _VSTD::addressof(__h->__value_.second));
+    __node_traits::construct(__na, _VSTD::addressof(__h->__value_.__cc.second));
     __h.get_deleter().__second_constructed = true;
-    return __h;
+    return _VSTD::move(__h);
 }
 
 #ifndef _LIBCPP_HAS_NO_VARIADICS
@@ -1172,23 +1153,21 @@ unordered_map<_Key, _Tp, _Hash, _Pred, _Alloc>::emplace(_Args&&... __args)
 }
 
 #endif  // _LIBCPP_HAS_NO_VARIADICS
-#else  // _LIBCPP_HAS_NO_RVALUE_REFERENCES
+#endif  // _LIBCPP_HAS_NO_RVALUE_REFERENCES
 
 template <class _Key, class _Tp, class _Hash, class _Pred, class _Alloc>
 typename unordered_map<_Key, _Tp, _Hash, _Pred, _Alloc>::__node_holder
-unordered_map<_Key, _Tp, _Hash, _Pred, _Alloc>::__construct_node(const key_type& __k)
+unordered_map<_Key, _Tp, _Hash, _Pred, _Alloc>::__construct_node_with_key(const key_type& __k)
 {
     __node_allocator& __na = __table_.__node_alloc();
     __node_holder __h(__node_traits::allocate(__na, 1), _Dp(__na));
-    __node_traits::construct(__na, _VSTD::addressof(__h->__value_.first), __k);
+    __node_traits::construct(__na, _VSTD::addressof(__h->__value_.__cc.first), __k);
     __h.get_deleter().__first_constructed = true;
-    __node_traits::construct(__na, _VSTD::addressof(__h->__value_.second));
+    __node_traits::construct(__na, _VSTD::addressof(__h->__value_.__cc.second));
     __h.get_deleter().__second_constructed = true;
     return _VSTD::move(__h);
 }
 
-#endif  // _LIBCPP_HAS_NO_RVALUE_REFERENCES
-
 template <class _Key, class _Tp, class _Hash, class _Pred, class _Alloc>
 template <class _InputIterator>
 inline _LIBCPP_INLINE_VISIBILITY
@@ -1207,7 +1186,7 @@ unordered_map<_Key, _Tp, _Hash, _Pred, _Alloc>::operator[](const key_type& __k)
     iterator __i = find(__k);
     if (__i != end())
         return __i->second;
-    __node_holder __h = __construct_node(__k);
+    __node_holder __h = __construct_node_with_key(__k);
     pair<iterator, bool> __r = __table_.__node_insert_unique(__h.get());
     __h.release();
     return __r.first->second;
@@ -1222,7 +1201,7 @@ unordered_map<_Key, _Tp, _Hash, _Pred, _Alloc>::operator[](key_type&& __k)
     iterator __i = find(__k);
     if (__i != end())
         return __i->second;
-    __node_holder __h = __construct_node(_VSTD::move(__k));
+    __node_holder __h = __construct_node_with_key(_VSTD::move(__k));
     pair<iterator, bool> __r = __table_.__node_insert_unique(__h.get());
     __h.release();
     return __r.first->second;
@@ -1304,13 +1283,56 @@ public:
     typedef _Pred                                          key_equal;
     typedef _Alloc                                         allocator_type;
     typedef pair<const key_type, mapped_type>              value_type;
+    typedef pair<key_type, mapped_type>                    __nc_value_type;
     typedef value_type&                                    reference;
     typedef const value_type&                              const_reference;
 
 private:
-    typedef pair<key_type, mapped_type>                    __value_type;
-    typedef __unordered_map_hasher<key_type, mapped_type, hasher>   __hasher;
-    typedef __unordered_map_equal<key_type, mapped_type, key_equal> __key_equal;
+#if __cplusplus >= 201103L
+    union __value_type
+    {
+        typedef typename unordered_multimap::value_type value_type;
+        typedef typename unordered_multimap::__nc_value_type __nc_value_type;
+        value_type __cc;
+        __nc_value_type __nc;
+
+        template <class ..._Args>
+        __value_type(_Args&& ...__args)
+            : __cc(std::forward<_Args>(__args)...) {}
+
+        __value_type(const __value_type& __v)
+            : __cc(std::move(__v.__cc)) {}
+
+        __value_type(__value_type&& __v)
+            : __nc(std::move(__v.__nc)) {}
+
+        __value_type& operator=(const __value_type& __v)
+            {__nc = __v.__cc; return *this;}
+
+        __value_type& operator=(__value_type&& __v)
+            {__nc = std::move(__v.__nc); return *this;}
+
+        ~__value_type() {__cc.~value_type();}
+    };
+#else
+    struct __value_type
+    {
+        typedef typename unordered_multimap::value_type value_type;
+        value_type __cc;
+
+        __value_type() {}
+
+        template <class _A0>
+        __value_type(const _A0& __a0)
+            : __cc(__a0) {}
+
+        template <class _A0, class _A1>
+        __value_type(const _A0& __a0, const _A1& __a1)
+            : __cc(__a0, __a1) {}
+    };
+#endif
+    typedef __unordered_map_hasher<key_type, __value_type, hasher>   __hasher;
+    typedef __unordered_map_equal<key_type, __value_type, key_equal> __key_equal;
     typedef typename allocator_traits<allocator_type>::template
 #ifndef _LIBCPP_HAS_NO_TEMPLATE_ALIASES
             rebind_alloc<__value_type>
@@ -1382,7 +1404,16 @@ public:
     _LIBCPP_INLINE_VISIBILITY
     unordered_multimap& operator=(const unordered_multimap& __u)
     {
+#if __cplusplus >= 201103L
         __table_ = __u.__table_;
+#else
+        __table_.clear();
+        __table_.hash_function() = __u.__table_.hash_function();
+        __table_.key_eq() = __u.__table_.key_eq();
+        __table_.max_load_factor() = __u.__table_.max_load_factor();
+        __table_.__copy_assign_alloc(__u.__table_);
+        insert(__u.begin(), __u.end());
+#endif
         return *this;
     }
 #ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES
@@ -1529,18 +1560,7 @@ private:
 #ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES
     __node_holder __construct_node();
     template <class _A0>
-        typename enable_if
-        <
-            is_constructible<value_type, _A0>::value,
-            __node_holder
-        >::type
-         __construct_node(_A0&& __a0);
-    template <class _A0>
-        typename enable_if
-        <
-            is_constructible<key_type, _A0>::value,
-            __node_holder
-        >::type
+        __node_holder
          __construct_node(_A0&& __a0);
 #ifndef _LIBCPP_HAS_NO_VARIADICS
     template <class _A0, class _A1, class ..._Args>
@@ -1727,11 +1747,7 @@ unordered_multimap<_Key, _Tp, _Hash, _Pred, _Alloc>::__construct_node()
 
 template <class _Key, class _Tp, class _Hash, class _Pred, class _Alloc>
 template <class _A0>
-typename enable_if
-<
-    is_constructible<pair<const _Key, _Tp>, _A0>::value,
-    typename unordered_multimap<_Key, _Tp, _Hash, _Pred, _Alloc>::__node_holder
->::type
+typename unordered_multimap<_Key, _Tp, _Hash, _Pred, _Alloc>::__node_holder
 unordered_multimap<_Key, _Tp, _Hash, _Pred, _Alloc>::__construct_node(_A0&& __a0)
 {
     __node_allocator& __na = __table_.__node_alloc();
@@ -1743,25 +1759,6 @@ unordered_multimap<_Key, _Tp, _Hash, _Pred, _Alloc>::__construct_node(_A0&& __a0
     return __h;
 }
 
-template <class _Key, class _Tp, class _Hash, class _Pred, class _Alloc>
-template <class _A0>
-typename enable_if
-<
-    is_constructible<_Key, _A0>::value,
-    typename unordered_multimap<_Key, _Tp, _Hash, _Pred, _Alloc>::__node_holder
->::type
-unordered_multimap<_Key, _Tp, _Hash, _Pred, _Alloc>::__construct_node(_A0&& __a0)
-{
-    __node_allocator& __na = __table_.__node_alloc();
-    __node_holder __h(__node_traits::allocate(__na, 1), _Dp(__na));
-    __node_traits::construct(__na, _VSTD::addressof(__h->__value_.first),
-                             _VSTD::forward<_A0>(__a0));
-    __h.get_deleter().__first_constructed = true;
-    __node_traits::construct(__na, _VSTD::addressof(__h->__value_.second));
-    __h.get_deleter().__second_constructed = true;
-    return __h;
-}
-
 #ifndef _LIBCPP_HAS_NO_VARIADICS
 
 template <class _Key, class _Tp, class _Hash, class _Pred, class _Alloc>
diff --git a/include/utility b/include/utility
index 2df4b361856a..ba656493c509 100644
--- a/include/utility
+++ b/include/utility
@@ -117,6 +117,27 @@ template<size_t I, class T1, class T2>
     typename tuple_element<I, std::pair<T1, T2> >::type&&
     get(std::pair<T1, T2>&&) noexcept;
 
+// C++14
+
+template<class T, T... I>
+struct integer_sequence
+{
+    typedef T value_type;
+
+    static constexpr size_t size() noexcept;
+};
+
+template<size_t... I>
+  using index_sequence = integer_sequence<size_t, I...>;
+
+template<class T, T N>
+  using make_integer_sequence = integer_sequence<T, 0, 1, ..., N-1>;
+template<size_t N>
+  using make_index_sequence = make_integer_sequence<size_t, N>;
+
+template<class... T>
+  using index_sequence_for = make_index_sequence<sizeof...(T)>;
+
 }  // std
 
 */
@@ -578,6 +599,92 @@ get(pair<_T1, _T2>&& __p) _NOEXCEPT
 
 #endif  // _LIBCPP_HAS_NO_RVALUE_REFERENCES
 
+#if _LIBCPP_STD_VER > 11
+
+template<class _Tp, _Tp... _Ip>
+struct _LIBCPP_TYPE_VIS integer_sequence
+{
+    typedef _Tp value_type;
+    static_assert( is_integral<_Tp>::value,
+                  "std::integer_sequence can only be instantiated with an integral type" );
+    static
+    _LIBCPP_INLINE_VISIBILITY
+    constexpr
+    size_t
+    size() noexcept { return sizeof...(_Ip); }
+};
+
+template<size_t... _Ip>
+    using index_sequence = integer_sequence<size_t, _Ip...>;
+
+namespace __detail {
+
+template<typename _Tp, size_t ..._Extra> struct __repeat;
+template<typename _Tp, _Tp ..._Np, size_t ..._Extra> struct __repeat<integer_sequence<_Tp, _Np...>, _Extra...> {
+  typedef integer_sequence<_Tp,
+                           _Np...,
+                           sizeof...(_Np) + _Np...,
+                           2 * sizeof...(_Np) + _Np...,
+                           3 * sizeof...(_Np) + _Np...,
+                           4 * sizeof...(_Np) + _Np...,
+                           5 * sizeof...(_Np) + _Np...,
+                           6 * sizeof...(_Np) + _Np...,
+                           7 * sizeof...(_Np) + _Np...,
+                           _Extra...> type;
+};
+
+template<size_t _Np> struct __parity;
+template<size_t _Np> struct __make : __parity<_Np % 8>::template __pmake<_Np> {};
+
+template<> struct __make<0> { typedef integer_sequence<size_t> type; };
+template<> struct __make<1> { typedef integer_sequence<size_t, 0> type; };
+template<> struct __make<2> { typedef integer_sequence<size_t, 0, 1> type; };
+template<> struct __make<3> { typedef integer_sequence<size_t, 0, 1, 2> type; };
+template<> struct __make<4> { typedef integer_sequence<size_t, 0, 1, 2, 3> type; };
+template<> struct __make<5> { typedef integer_sequence<size_t, 0, 1, 2, 3, 4> type; };
+template<> struct __make<6> { typedef integer_sequence<size_t, 0, 1, 2, 3, 4, 5> type; };
+template<> struct __make<7> { typedef integer_sequence<size_t, 0, 1, 2, 3, 4, 5, 6> type; };
+
+template<> struct __parity<0> { template<size_t _Np> struct __pmake : __repeat<typename __make<_Np / 8>::type> {}; };
+template<> struct __parity<1> { template<size_t _Np> struct __pmake : __repeat<typename __make<_Np / 8>::type, _Np - 1> {}; };
+template<> struct __parity<2> { template<size_t _Np> struct __pmake : __repeat<typename __make<_Np / 8>::type, _Np - 2, _Np - 1> {}; };
+template<> struct __parity<3> { template<size_t _Np> struct __pmake : __repeat<typename __make<_Np / 8>::type, _Np - 3, _Np - 2, _Np - 1> {}; };
+template<> struct __parity<4> { template<size_t _Np> struct __pmake : __repeat<typename __make<_Np / 8>::type, _Np - 4, _Np - 3, _Np - 2, _Np - 1> {}; };
+template<> struct __parity<5> { template<size_t _Np> struct __pmake : __repeat<typename __make<_Np / 8>::type, _Np - 5, _Np - 4, _Np - 3, _Np - 2, _Np - 1> {}; };
+template<> struct __parity<6> { template<size_t _Np> struct __pmake : __repeat<typename __make<_Np / 8>::type, _Np - 6, _Np - 5, _Np - 4, _Np - 3, _Np - 2, _Np - 1> {}; };
+template<> struct __parity<7> { template<size_t _Np> struct __pmake : __repeat<typename __make<_Np / 8>::type, _Np - 7, _Np - 6, _Np - 5, _Np - 4, _Np - 3, _Np - 2, _Np - 1> {}; };
+
+template<typename _Tp, typename _Up> struct __convert {
+  template<typename> struct __result;
+  template<_Tp ..._Np> struct __result<integer_sequence<_Tp, _Np...> > { typedef integer_sequence<_Up, _Np...> type; };
+};
+template<typename _Tp> struct __convert<_Tp, _Tp> { template<typename _Up> struct __result { typedef _Up type; }; };
+
+}
+
+template<typename _Tp, _Tp _Np> using __make_integer_sequence_unchecked =
+  typename __detail::__convert<size_t, _Tp>::template __result<typename __detail::__make<_Np>::type>::type;
+
+template <class _Tp, _Tp _Ep>
+struct __make_integer_sequence
+{
+    static_assert(is_integral<_Tp>::value,
+                  "std::make_integer_sequence can only be instantiated with an integral type" );
+    static_assert(0 <= _Ep, "std::make_integer_sequence input shall not be negative");
+    typedef __make_integer_sequence_unchecked<_Tp, _Ep> type;
+};
+
+template<class _Tp, _Tp _Np>
+    using make_integer_sequence = typename __make_integer_sequence<_Tp, _Np>::type;
+
+template<size_t _Np>
+    using make_index_sequence = make_integer_sequence<size_t, _Np>;
+
+template<class... _Tp>
+    using index_sequence_for = make_index_sequence<sizeof...(_Tp)>;
+  
+#endif  // _LIBCPP_STD_VER > 11
+
 _LIBCPP_END_NAMESPACE_STD
 
 #endif  // _LIBCPP_UTILITY
diff --git a/include/vector b/include/vector
index e04c2673b2e2..046d92dc91b0 100644
--- a/include/vector
+++ b/include/vector
@@ -365,12 +365,7 @@ protected:
         {return static_cast<size_type>(__end_cap() - __begin_);}
 
     _LIBCPP_INLINE_VISIBILITY
-    void __destruct_at_end(const_pointer __new_last) _NOEXCEPT
-        {__destruct_at_end(__new_last, false_type());}
-    _LIBCPP_INLINE_VISIBILITY
-    void __destruct_at_end(const_pointer __new_last, false_type) _NOEXCEPT;
-    _LIBCPP_INLINE_VISIBILITY
-    void __destruct_at_end(const_pointer __new_last, true_type) _NOEXCEPT;
+    void __destruct_at_end(pointer __new_last) _NOEXCEPT;
 
     _LIBCPP_INLINE_VISIBILITY
     void __copy_assign_alloc(const __vector_base& __c)
@@ -437,43 +432,35 @@ private:
 template <class _Tp, class _Allocator>
 _LIBCPP_INLINE_VISIBILITY inline
 void
-__vector_base<_Tp, _Allocator>::__destruct_at_end(const_pointer __new_last, false_type) _NOEXCEPT
+__vector_base<_Tp, _Allocator>::__destruct_at_end(pointer __new_last) _NOEXCEPT
 {
     while (__new_last != __end_)
-        __alloc_traits::destroy(__alloc(), const_cast<pointer>(--__end_));
-}
-
-template <class _Tp, class _Allocator>
-_LIBCPP_INLINE_VISIBILITY inline
-void
-__vector_base<_Tp, _Allocator>::__destruct_at_end(const_pointer __new_last, true_type) _NOEXCEPT
-{
-    __end_ = const_cast<pointer>(__new_last);
+        __alloc_traits::destroy(__alloc(), _VSTD::__to_raw_pointer(--__end_));
 }
 
 template <class _Tp, class _Allocator>
 _LIBCPP_INLINE_VISIBILITY inline
 __vector_base<_Tp, _Allocator>::__vector_base()
         _NOEXCEPT_(is_nothrow_default_constructible<allocator_type>::value)
-    : __begin_(0),
-      __end_(0),
-      __end_cap_(0)
+    : __begin_(nullptr),
+      __end_(nullptr),
+      __end_cap_(nullptr)
 {
 }
 
 template <class _Tp, class _Allocator>
 _LIBCPP_INLINE_VISIBILITY inline
 __vector_base<_Tp, _Allocator>::__vector_base(const allocator_type& __a)
-    : __begin_(0),
-      __end_(0),
-      __end_cap_(0, __a)
+    : __begin_(nullptr),
+      __end_(nullptr),
+      __end_cap_(nullptr, __a)
 {
 }
 
 template <class _Tp, class _Allocator>
 __vector_base<_Tp, _Allocator>::~__vector_base()
 {
-    if (__begin_ != 0)
+    if (__begin_ != nullptr)
     {
         clear();
         __alloc_traits::deallocate(__alloc(), __begin_, capacity());
@@ -797,7 +784,7 @@ private:
         _NOEXCEPT_(is_nothrow_move_assignable<allocator_type>::value);
     void __move_assign(vector& __c, false_type);
     _LIBCPP_INLINE_VISIBILITY
-    void __destruct_at_end(const_pointer __new_last) _NOEXCEPT
+    void __destruct_at_end(pointer __new_last) _NOEXCEPT
     {
 #if _LIBCPP_DEBUG_LEVEL >= 2
         __c_node* __c = __get_db()->__find_c_and_lock(this);
@@ -878,11 +865,11 @@ template <class _Tp, class _Allocator>
 void
 vector<_Tp, _Allocator>::deallocate() _NOEXCEPT
 {
-    if (this->__begin_ != 0)
+    if (this->__begin_ != nullptr)
     {
         clear();
         __alloc_traits::deallocate(this->__alloc(), this->__begin_, capacity());
-        this->__begin_ = this->__end_ = this->__end_cap() = 0;
+        this->__begin_ = this->__end_ = this->__end_cap() = nullptr;
     }
 }
 
@@ -1171,7 +1158,7 @@ vector<_Tp, _Allocator>::vector(vector&& __x)
     this->__begin_ = __x.__begin_;
     this->__end_ = __x.__end_;
     this->__end_cap() = __x.__end_cap();
-    __x.__begin_ = __x.__end_ = __x.__end_cap() = 0;
+    __x.__begin_ = __x.__end_ = __x.__end_cap() = nullptr;
 }
 
 template <class _Tp, class _Allocator>
@@ -1597,7 +1584,8 @@ vector<_Tp, _Allocator>::erase(const_iterator __position)
 #endif
     _LIBCPP_ASSERT(__position != end(),
         "vector::erase(iterator) called with a non-dereferenceable iterator");
-    pointer __p = const_cast<pointer>(&*__position);
+    difference_type __ps = __position - cbegin();
+    pointer __p = this->__begin_ + __ps;
     iterator __r = __make_iter(__p);
     this->__destruct_at_end(_VSTD::move(__p + 1, this->__end_, __p));
     return __r;
@@ -1943,9 +1931,9 @@ template <class _Tp, class _Allocator>
 bool
 vector<_Tp, _Allocator>::__invariants() const
 {
-    if (this->__begin_ == 0)
+    if (this->__begin_ == nullptr)
     {
-        if (this->__end_ != 0 || this->__end_cap() != 0)
+        if (this->__end_ != nullptr || this->__end_cap() != nullptr)
             return false;
     }
     else
@@ -2307,7 +2295,7 @@ private:
         {return const_iterator(__begin_ + __pos / __bits_per_word, static_cast<unsigned>(__pos % __bits_per_word));}
     _LIBCPP_INLINE_VISIBILITY
     iterator __const_iterator_cast(const_iterator __p) _NOEXCEPT
-        {return iterator(const_cast<__storage_pointer>(__p.__seg_), __p.__ctz_);}
+        {return begin() + (__p - cbegin());}
 #endif  // _LIBCPP_DEBUG
 
     _LIBCPP_INLINE_VISIBILITY
@@ -2414,11 +2402,11 @@ template <class _Allocator>
 void
 vector<bool, _Allocator>::deallocate() _NOEXCEPT
 {
-    if (this->__begin_ != 0)
+    if (this->__begin_ != nullptr)
     {
         __storage_traits::deallocate(this->__alloc(), this->__begin_, __cap());
         __invalidate_all_iterators();
-        this->__begin_ = 0;
+        this->__begin_ = nullptr;
         this->__size_ = this->__cap() = 0;
     }
 }
@@ -2481,7 +2469,7 @@ template <class _Allocator>
 _LIBCPP_INLINE_VISIBILITY inline
 vector<bool, _Allocator>::vector()
         _NOEXCEPT_(is_nothrow_default_constructible<allocator_type>::value)
-    : __begin_(0),
+    : __begin_(nullptr),
       __size_(0),
       __cap_alloc_(0)
 {
@@ -2490,7 +2478,7 @@ vector<bool, _Allocator>::vector()
 template <class _Allocator>
 _LIBCPP_INLINE_VISIBILITY inline
 vector<bool, _Allocator>::vector(const allocator_type& __a)
-    : __begin_(0),
+    : __begin_(nullptr),
       __size_(0),
       __cap_alloc_(0, static_cast<__storage_allocator>(__a))
 {
@@ -2498,7 +2486,7 @@ vector<bool, _Allocator>::vector(const allocator_type& __a)
 
 template <class _Allocator>
 vector<bool, _Allocator>::vector(size_type __n)
-    : __begin_(0),
+    : __begin_(nullptr),
       __size_(0),
       __cap_alloc_(0)
 {
@@ -2511,7 +2499,7 @@ vector<bool, _Allocator>::vector(size_type __n)
 
 template <class _Allocator>
 vector<bool, _Allocator>::vector(size_type __n, const value_type& __x)
-    : __begin_(0),
+    : __begin_(nullptr),
       __size_(0),
       __cap_alloc_(0)
 {
@@ -2524,7 +2512,7 @@ vector<bool, _Allocator>::vector(size_type __n, const value_type& __x)
 
 template <class _Allocator>
 vector<bool, _Allocator>::vector(size_type __n, const value_type& __x, const allocator_type& __a)
-    : __begin_(0),
+    : __begin_(nullptr),
       __size_(0),
       __cap_alloc_(0, static_cast<__storage_allocator>(__a))
 {
@@ -2540,7 +2528,7 @@ template <class _InputIterator>
 vector<bool, _Allocator>::vector(_InputIterator __first, _InputIterator __last,
        typename enable_if<__is_input_iterator  <_InputIterator>::value &&
                          !__is_forward_iterator<_InputIterator>::value>::type*)
-    : __begin_(0),
+    : __begin_(nullptr),
       __size_(0),
       __cap_alloc_(0)
 {
@@ -2554,7 +2542,7 @@ vector<bool, _Allocator>::vector(_InputIterator __first, _InputIterator __last,
     }
     catch (...)
     {
-        if (__begin_ != 0)
+        if (__begin_ != nullptr)
             __storage_traits::deallocate(__alloc(), __begin_, __cap());
         __invalidate_all_iterators();
         throw;
@@ -2567,7 +2555,7 @@ template <class _InputIterator>
 vector<bool, _Allocator>::vector(_InputIterator __first, _InputIterator __last, const allocator_type& __a,
        typename enable_if<__is_input_iterator  <_InputIterator>::value &&
                          !__is_forward_iterator<_InputIterator>::value>::type*)
-    : __begin_(0),
+    : __begin_(nullptr),
       __size_(0),
       __cap_alloc_(0, static_cast<__storage_allocator>(__a))
 {
@@ -2581,7 +2569,7 @@ vector<bool, _Allocator>::vector(_InputIterator __first, _InputIterator __last,
     }
     catch (...)
     {
-        if (__begin_ != 0)
+        if (__begin_ != nullptr)
             __storage_traits::deallocate(__alloc(), __begin_, __cap());
         __invalidate_all_iterators();
         throw;
@@ -2593,7 +2581,7 @@ template <class _Allocator>
 template <class _ForwardIterator>
 vector<bool, _Allocator>::vector(_ForwardIterator __first, _ForwardIterator __last,
                                 typename enable_if<__is_forward_iterator<_ForwardIterator>::value>::type*)
-    : __begin_(0),
+    : __begin_(nullptr),
       __size_(0),
       __cap_alloc_(0)
 {
@@ -2609,7 +2597,7 @@ template <class _Allocator>
 template <class _ForwardIterator>
 vector<bool, _Allocator>::vector(_ForwardIterator __first, _ForwardIterator __last, const allocator_type& __a,
                                 typename enable_if<__is_forward_iterator<_ForwardIterator>::value>::type*)
-    : __begin_(0),
+    : __begin_(nullptr),
       __size_(0),
       __cap_alloc_(0, static_cast<__storage_allocator>(__a))
 {
@@ -2625,7 +2613,7 @@ vector<bool, _Allocator>::vector(_ForwardIterator __first, _ForwardIterator __la
 
 template <class _Allocator>
 vector<bool, _Allocator>::vector(initializer_list<value_type> __il)
-    : __begin_(0),
+    : __begin_(nullptr),
       __size_(0),
       __cap_alloc_(0)
 {
@@ -2639,7 +2627,7 @@ vector<bool, _Allocator>::vector(initializer_list<value_type> __il)
 
 template <class _Allocator>
 vector<bool, _Allocator>::vector(initializer_list<value_type> __il, const allocator_type& __a)
-    : __begin_(0),
+    : __begin_(nullptr),
       __size_(0),
       __cap_alloc_(0, static_cast<__storage_allocator>(__a))
 {
@@ -2656,7 +2644,7 @@ vector<bool, _Allocator>::vector(initializer_list<value_type> __il, const alloca
 template <class _Allocator>
 vector<bool, _Allocator>::~vector()
 {
-    if (__begin_ != 0)
+    if (__begin_ != nullptr)
         __storage_traits::deallocate(__alloc(), __begin_, __cap());
 #ifdef _LIBCPP_DEBUG
     __invalidate_all_iterators();
@@ -2665,7 +2653,7 @@ vector<bool, _Allocator>::~vector()
 
 template <class _Allocator>
 vector<bool, _Allocator>::vector(const vector& __v)
-    : __begin_(0),
+    : __begin_(nullptr),
       __size_(0),
       __cap_alloc_(0, __storage_traits::select_on_container_copy_construction(__v.__alloc()))
 {
@@ -2678,7 +2666,7 @@ vector<bool, _Allocator>::vector(const vector& __v)
 
 template <class _Allocator>
 vector<bool, _Allocator>::vector(const vector& __v, const allocator_type& __a)
-    : __begin_(0),
+    : __begin_(nullptr),
       __size_(0),
       __cap_alloc_(0, __a)
 {
@@ -2720,14 +2708,14 @@ vector<bool, _Allocator>::vector(vector&& __v)
       __size_(__v.__size_),
       __cap_alloc_(__v.__cap_alloc_)
 {
-    __v.__begin_ = 0;
+    __v.__begin_ = nullptr;
     __v.__size_ = 0;
     __v.__cap() = 0;
 }
 
 template <class _Allocator>
 vector<bool, _Allocator>::vector(vector&& __v, const allocator_type& __a)
-    : __begin_(0),
+    : __begin_(nullptr),
       __size_(0),
       __cap_alloc_(0, __a)
 {
@@ -3123,7 +3111,7 @@ template <class _Allocator>
 bool
 vector<bool, _Allocator>::__invariants() const
 {
-    if (this->__begin_ == 0)
+    if (this->__begin_ == nullptr)
     {
         if (this->__size_ != 0 || this->__cap() != 0)
             return false;
diff --git a/src/debug.cpp b/src/debug.cpp
index 06040af902af..04d570ed2291 100644
--- a/src/debug.cpp
+++ b/src/debug.cpp
@@ -143,7 +143,7 @@ __libcpp_db::__insert_c(void* __c)
     if (__csz_ + 1 > static_cast<size_t>(__cend_ - __cbeg_))
     {
         size_t nc = __next_prime(2*static_cast<size_t>(__cend_ - __cbeg_) + 1);
-        __c_node** cbeg = (__c_node**)calloc(nc, sizeof(void*));
+        __c_node** cbeg = static_cast<__c_node**>(calloc(nc, sizeof(void*)));
         if (cbeg == nullptr)
 #ifndef _LIBCPP_NO_EXCEPTIONS
             throw bad_alloc();
@@ -168,7 +168,8 @@ __libcpp_db::__insert_c(void* __c)
     }
     size_t hc = hash<void*>()(__c) % static_cast<size_t>(__cend_ - __cbeg_);
     __c_node* p = __cbeg_[hc];
-    __c_node* r = __cbeg_[hc] = (__c_node*)malloc(sizeof(__c_node));
+    __c_node* r = __cbeg_[hc] =
+      static_cast<__c_node*>(malloc(sizeof(__c_node)));
     if (__cbeg_[hc] == nullptr)
 #ifndef _LIBCPP_NO_EXCEPTIONS
         throw bad_alloc();
@@ -407,7 +408,8 @@ __c_node::__add(__i_node* i)
         size_t nc = 2*static_cast<size_t>(cap_ - beg_);
         if (nc == 0)
             nc = 1;
-        __i_node** beg = (__i_node**)malloc(nc * sizeof(__i_node*));
+        __i_node** beg =
+           static_cast<__i_node**>(malloc(nc * sizeof(__i_node*)));
         if (beg == nullptr)
 #ifndef _LIBCPP_NO_EXCEPTIONS
             throw bad_alloc();
@@ -433,7 +435,7 @@ __libcpp_db::__insert_iterator(void* __i)
     if (__isz_ + 1 > static_cast<size_t>(__iend_ - __ibeg_))
     {
         size_t nc = __next_prime(2*static_cast<size_t>(__iend_ - __ibeg_) + 1);
-        __i_node** ibeg = (__i_node**)calloc(nc, sizeof(void*));
+        __i_node** ibeg = static_cast<__i_node**>(calloc(nc, sizeof(void*)));
         if (ibeg == nullptr)
 #ifndef _LIBCPP_NO_EXCEPTIONS
             throw bad_alloc();
@@ -458,7 +460,8 @@ __libcpp_db::__insert_iterator(void* __i)
     }
     size_t hi = hash<void*>()(__i) % static_cast<size_t>(__iend_ - __ibeg_);
     __i_node* p = __ibeg_[hi];
-    __i_node* r = __ibeg_[hi] = (__i_node*)malloc(sizeof(__i_node));
+    __i_node* r = __ibeg_[hi] =
+      static_cast<__i_node*>(malloc(sizeof(__i_node)));
     if (r == nullptr)
 #ifndef _LIBCPP_NO_EXCEPTIONS
         throw bad_alloc();
diff --git a/src/hash.cpp b/src/hash.cpp
index 75e773a3a647..388ab2ebe175 100644
--- a/src/hash.cpp
+++ b/src/hash.cpp
@@ -12,7 +12,9 @@
 #include "stdexcept"
 #include "type_traits"
 
+#ifdef __clang__
 #pragma clang diagnostic ignored "-Wtautological-constant-out-of-range-compare"
+#endif
 
 _LIBCPP_BEGIN_NAMESPACE_STD
 
diff --git a/src/iostream.cpp b/src/iostream.cpp
index 7fc71df44a45..f413681f0064 100644
--- a/src/iostream.cpp
+++ b/src/iostream.cpp
@@ -54,13 +54,13 @@ ios_base::Init::Init()
 
 ios_base::Init::~Init()
 {
-    ostream* cout_ptr = (ostream*)cout;
-    ostream* clog_ptr = (ostream*)clog;
+    ostream* cout_ptr = reinterpret_cast<ostream*>(cout);
+    ostream* clog_ptr = reinterpret_cast<ostream*>(clog);
     cout_ptr->flush();
     clog_ptr->flush();
 
-    wostream* wcout_ptr = (wostream*)wcout;
-    wostream* wclog_ptr = (wostream*)wclog;
+    wostream* wcout_ptr = reinterpret_cast<wostream*>(wcout);
+    wostream* wclog_ptr = reinterpret_cast<wostream*>(wclog);
     wcout_ptr->flush();
     wclog_ptr->flush();
 }
diff --git a/src/locale.cpp b/src/locale.cpp
index 49c1cf22301f..b15f077cfb12 100644
--- a/src/locale.cpp
+++ b/src/locale.cpp
@@ -230,8 +230,10 @@ locale::__imp::__imp(const string& name, size_t refs)
 
 // NOTE avoid the `base class should be explicitly initialized in the
 // copy constructor` warning emitted by GCC
+#if defined(__clang__) || _GNUC_VER >= 406
 #pragma GCC diagnostic push
 #pragma GCC diagnostic ignored "-Wextra"
+#endif
 
 locale::__imp::__imp(const __imp& other)
     : facets_(max<size_t>(N, other.facets_.size())),
@@ -243,7 +245,9 @@ locale::__imp::__imp(const __imp& other)
             facets_[i]->__add_shared();
 }
 
+#if defined(__clang__) || _GNUC_VER >= 406
 #pragma GCC diagnostic pop
+#endif
 
 locale::__imp::__imp(const __imp& other, const string& name, locale::category c)
     : facets_(N),
@@ -786,7 +790,7 @@ ctype<wchar_t>::do_toupper(char_type c) const
 {
 #ifdef _LIBCPP_HAS_DEFAULTRUNELOCALE
     return isascii(c) ? _DefaultRuneLocale.__mapupper[c] : c;
-#elif defined(__GLIBC__) || defined(EMSCRIPTEN)
+#elif defined(__GLIBC__) || defined(EMSCRIPTEN) || defined(__NetBSD__)
     return isascii(c) ? ctype<char>::__classic_upper_table()[c] : c;
 #else
     return (isascii(c) && iswlower_l(c, __cloc())) ? c-L'a'+L'A' : c;
@@ -799,7 +803,7 @@ ctype<wchar_t>::do_toupper(char_type* low, const char_type* high) const
     for (; low != high; ++low)
 #ifdef _LIBCPP_HAS_DEFAULTRUNELOCALE
         *low = isascii(*low) ? _DefaultRuneLocale.__mapupper[*low] : *low;
-#elif defined(__GLIBC__) || defined(EMSCRIPTEN)
+#elif defined(__GLIBC__) || defined(EMSCRIPTEN) || defined(__NetBSD__)
         *low = isascii(*low) ? ctype<char>::__classic_upper_table()[*low]
                              : *low;
 #else
@@ -813,7 +817,7 @@ ctype<wchar_t>::do_tolower(char_type c) const
 {
 #ifdef _LIBCPP_HAS_DEFAULTRUNELOCALE
     return isascii(c) ? _DefaultRuneLocale.__maplower[c] : c;
-#elif defined(__GLIBC__) || defined(EMSCRIPTEN)
+#elif defined(__GLIBC__) || defined(EMSCRIPTEN) || defined(__NetBSD__)
     return isascii(c) ? ctype<char>::__classic_lower_table()[c] : c;
 #else
     return (isascii(c) && isupper_l(c, __cloc())) ? c-L'A'+'a' : c;
@@ -826,7 +830,7 @@ ctype<wchar_t>::do_tolower(char_type* low, const char_type* high) const
     for (; low != high; ++low)
 #ifdef _LIBCPP_HAS_DEFAULTRUNELOCALE
         *low = isascii(*low) ? _DefaultRuneLocale.__maplower[*low] : *low;
-#elif defined(__GLIBC__) || defined(EMSCRIPTEN)
+#elif defined(__GLIBC__) || defined(EMSCRIPTEN) || defined(__NetBSD__)
         *low = isascii(*low) ? ctype<char>::__classic_lower_table()[*low]
                              : *low;
 #else
@@ -893,9 +897,11 @@ ctype<char>::do_toupper(char_type c) const
 #ifdef _LIBCPP_HAS_DEFAULTRUNELOCALE
     return isascii(c) ?
       static_cast<char>(_DefaultRuneLocale.__mapupper[static_cast<ptrdiff_t>(c)]) : c;
+#elif defined(__NetBSD__)
+    return static_cast<char>(__classic_upper_table()[static_cast<unsigned char>(c)]);
 #elif defined(__GLIBC__) || defined(EMSCRIPTEN)
     return isascii(c) ? 
-      static_cast<char>(__classic_upper_table()[static_cast<size_t>(c)]) : c;
+      static_cast<char>(__classic_upper_table()[static_cast<unsigned char>(c)]) : c;
 #else
     return (isascii(c) && islower_l(c, __cloc())) ? c-'a'+'A' : c;
 #endif
@@ -908,6 +914,8 @@ ctype<char>::do_toupper(char_type* low, const char_type* high) const
 #ifdef _LIBCPP_HAS_DEFAULTRUNELOCALE
         *low = isascii(*low) ?
           static_cast<char>(_DefaultRuneLocale.__mapupper[static_cast<ptrdiff_t>(*low)]) : *low;
+#elif defined(__NetBSD__)
+        *low = static_cast<char>(__classic_upper_table()[static_cast<unsigned char>(*low)]);
 #elif defined(__GLIBC__) || defined(EMSCRIPTEN)
         *low = isascii(*low) ?
           static_cast<char>(__classic_upper_table()[static_cast<size_t>(*low)]) : *low;
@@ -923,7 +931,9 @@ ctype<char>::do_tolower(char_type c) const
 #ifdef _LIBCPP_HAS_DEFAULTRUNELOCALE
     return isascii(c) ?
       static_cast<char>(_DefaultRuneLocale.__maplower[static_cast<ptrdiff_t>(c)]) : c;
-#elif defined(__GLIBC__) || defined(EMSCRIPTEN)
+#elif defined(__NetBSD__)
+    return static_cast<char>(__classic_lower_table()[static_cast<unsigned char>(c)]);
+#elif defined(__GLIBC__) || defined(EMSCRIPTEN) || defined(__NetBSD__)
     return isascii(c) ?
       static_cast<char>(__classic_lower_table()[static_cast<size_t>(c)]) : c;
 #else
@@ -937,6 +947,8 @@ ctype<char>::do_tolower(char_type* low, const char_type* high) const
     for (; low != high; ++low)
 #ifdef _LIBCPP_HAS_DEFAULTRUNELOCALE
         *low = isascii(*low) ? static_cast<char>(_DefaultRuneLocale.__maplower[static_cast<ptrdiff_t>(*low)]) : *low;
+#elif defined(__NetBSD__)
+        *low = static_cast<char>(__classic_lower_table()[static_cast<unsigned char>(*low)]);
 #elif defined(__GLIBC__) || defined(EMSCRIPTEN)
         *low = isascii(*low) ? static_cast<char>(__classic_lower_table()[static_cast<size_t>(*low)]) : *low;
 #else
@@ -989,6 +1001,8 @@ ctype<char>::classic_table()  _NOEXCEPT
 {
 #if defined(__APPLE__) || defined(__FreeBSD__)
     return _DefaultRuneLocale.__runetype;
+#elif defined(__NetBSD__)
+    return _C_ctype_tab_ + 1;
 #elif defined(__GLIBC__)
     return __cloc()->__ctype_b;
 #elif __sun__
@@ -1020,9 +1034,20 @@ ctype<char>::__classic_upper_table() _NOEXCEPT
 {
     return __cloc()->__ctype_toupper;
 }
-#endif // __GLIBC__
+#elif __NetBSD__
+const short*
+ctype<char>::__classic_lower_table() _NOEXCEPT
+{
+    return _C_tolower_tab_ + 1;
+}
 
-#if defined(EMSCRIPTEN)
+const short*
+ctype<char>::__classic_upper_table() _NOEXCEPT
+{
+    return _C_toupper_tab_ + 1;
+}
+
+#elif defined(EMSCRIPTEN)
 const int*
 ctype<char>::__classic_lower_table() _NOEXCEPT
 {
@@ -1034,7 +1059,7 @@ ctype<char>::__classic_upper_table() _NOEXCEPT
 {
     return *__ctype_toupper_loc();
 }
-#endif // EMSCRIPTEN
+#endif // __GLIBC__ || EMSCRIPTEN || __NETBSD__
 
 // template <> class ctype_byname<char>
 
@@ -1068,28 +1093,28 @@ ctype_byname<char>::~ctype_byname()
 char
 ctype_byname<char>::do_toupper(char_type c) const
 {
-    return static_cast<char>(toupper_l(c, __l));
+    return static_cast<char>(toupper_l(static_cast<unsigned char>(c), __l));
 }
 
 const char*
 ctype_byname<char>::do_toupper(char_type* low, const char_type* high) const
 {
     for (; low != high; ++low)
-        *low = static_cast<char>(toupper_l(*low, __l));
+        *low = static_cast<char>(toupper_l(static_cast<unsigned char>(*low), __l));
     return low;
 }
 
 char
 ctype_byname<char>::do_tolower(char_type c) const
 {
-    return static_cast<char>(tolower_l(c, __l));
+    return static_cast<char>(tolower_l(static_cast<unsigned char>(c), __l));
 }
 
 const char*
 ctype_byname<char>::do_tolower(char_type* low, const char_type* high) const
 {
     for (; low != high; ++low)
-        *low = static_cast<char>(tolower_l(*low, __l));
+        *low = static_cast<char>(tolower_l(static_cast<unsigned char>(*low), __l));
     return low;
 }
 
@@ -1372,7 +1397,7 @@ locale::id codecvt<wchar_t, char, mbstate_t>::id;
 
 codecvt<wchar_t, char, mbstate_t>::codecvt(size_t refs)
     : locale::facet(refs),
-      __l(0)
+      __l(_LIBCPP_GET_C_LOCALE)
 {
 }
 
@@ -1389,7 +1414,7 @@ codecvt<wchar_t, char, mbstate_t>::codecvt(const char* nm, size_t refs)
 
 codecvt<wchar_t, char, mbstate_t>::~codecvt()
 {
-    if (__l != 0)
+    if (__l != _LIBCPP_GET_C_LOCALE)
         freelocale(__l);
 }
 
@@ -5315,7 +5340,7 @@ __time_put::__time_put(const string& nm)
 
 __time_put::~__time_put()
 {
-    if (__loc_)
+    if (__loc_ != _LIBCPP_GET_C_LOCALE)
         freelocale(__loc_);
 }
 
diff --git a/src/stdexcept.cpp b/src/stdexcept.cpp
index 0c4e8323abf3..8d25f3ee5427 100644
--- a/src/stdexcept.cpp
+++ b/src/stdexcept.cpp
@@ -61,7 +61,7 @@ __libcpp_nmstr::__libcpp_nmstr(const char* msg)
     c[0] = c[1] = len;
     str_ += offset;
     count() = 0;
-    std::strcpy(const_cast<char*>(c_str()), msg);
+    std::memcpy(const_cast<char*>(c_str()), msg, len + 1);
 }
 
 inline
diff --git a/src/string.cpp b/src/string.cpp
index c71af4feb944..c6fe408ca1ca 100644
--- a/src/string.cpp
+++ b/src/string.cpp
@@ -11,6 +11,8 @@
 #include "cstdlib"
 #include "cwchar"
 #include "cerrno"
+#include "limits"
+#include "stdexcept"
 #ifdef _WIN32
 #include "support/win32/support.h"
 #endif // _WIN32
@@ -26,662 +28,499 @@ template
     string
     operator+<char, char_traits<char>, allocator<char> >(char const*, string const&);
 
-int
-stoi(const string& str, size_t* idx, int base)
+namespace
+{
+
+template<typename T>
+inline
+void throw_helper( const string& msg )
+{
+#ifndef _LIBCPP_NO_EXCEPTIONS
+    throw T( msg );
+#else
+    abort();
+#endif
+}
+
+inline
+void throw_from_string_out_of_range( const string& func )
+{
+    throw_helper<out_of_range>(func + ": out of range");
+}
+
+inline
+void throw_from_string_invalid_arg( const string& func )
+{
+    throw_helper<invalid_argument>(func + ": no conversion");
+}
+
+// as_integer
+
+template<typename V, typename S, typename F>
+inline
+V
+as_integer_helper(const string& func, const S& str, size_t* idx, int base, F f)
 {
-    char* ptr;
-    const char* const p = str.c_str();
+    typename S::value_type* ptr;
+    const typename S::value_type* const p = str.c_str();
     typename remove_reference<decltype(errno)>::type errno_save = errno;
     errno = 0;
-    long r = strtol(p, &ptr, base);
+    V r = f(p, &ptr, base);
     swap(errno, errno_save);
-#ifndef _LIBCPP_NO_EXCEPTIONS
-    if (errno_save == ERANGE || r < numeric_limits<int>::min() ||
-                                numeric_limits<int>::max() < r)
-        throw out_of_range("stoi: out of range");
+    if (errno_save == ERANGE)
+        throw_from_string_out_of_range(func);
     if (ptr == p)
-        throw invalid_argument("stoi: no conversion");
-#endif  // _LIBCPP_NO_EXCEPTIONS
+        throw_from_string_invalid_arg(func);
     if (idx)
         *idx = static_cast<size_t>(ptr - p);
+    return r;
+}
+
+template<typename V, typename S>
+inline
+V
+as_integer(const string& func, const S& s, size_t* idx, int base);
+
+// string
+template<>
+inline
+int
+as_integer(const string& func, const string& s, size_t* idx, int base )
+{
+    // Use long as no Stantard string to integer exists.
+    long r = as_integer_helper<long>( func, s, idx, base, strtol );
+    if (r < numeric_limits<int>::min() || numeric_limits<int>::max() < r)
+        throw_from_string_out_of_range(func);
     return static_cast<int>(r);
 }
 
+template<>
+inline
+long
+as_integer(const string& func, const string& s, size_t* idx, int base )
+{
+    return as_integer_helper<long>( func, s, idx, base, strtol );
+}
+
+template<>
+inline
+unsigned long
+as_integer( const string& func, const string& s, size_t* idx, int base )
+{
+    return as_integer_helper<unsigned long>( func, s, idx, base, strtoul );
+}
+
+template<>
+inline
+long long
+as_integer( const string& func, const string& s, size_t* idx, int base )
+{
+    return as_integer_helper<long long>( func, s, idx, base, strtoll );
+}
+
+template<>
+inline
+unsigned long long
+as_integer( const string& func, const string& s, size_t* idx, int base )
+{
+    return as_integer_helper<unsigned long long>( func, s, idx, base, strtoull );
+}
+
+// wstring
+template<>
+inline
 int
-stoi(const wstring& str, size_t* idx, int base)
+as_integer( const string& func, const wstring& s, size_t* idx, int base )
 {
-    wchar_t* ptr;
-    const wchar_t* const p = str.c_str();
-    typename remove_reference<decltype(errno)>::type errno_save = errno;
-    errno = 0;
-    long r = wcstol(p, &ptr, base);
-    swap(errno, errno_save);
-#ifndef _LIBCPP_NO_EXCEPTIONS
-    if (errno_save == ERANGE || r < numeric_limits<int>::min() ||
-                                numeric_limits<int>::max() < r)
-        throw out_of_range("stoi: out of range");
-    if (ptr == p)
-        throw invalid_argument("stoi: no conversion");
-#endif  // _LIBCPP_NO_EXCEPTIONS
-    if (idx)
-        *idx = static_cast<size_t>(ptr - p);
+    // Use long as no Stantard string to integer exists.
+    long r = as_integer_helper<long>( func, s, idx, base, wcstol );
+    if (r < numeric_limits<int>::min() || numeric_limits<int>::max() < r)
+        throw_from_string_out_of_range(func);
     return static_cast<int>(r);
 }
 
+template<>
+inline
 long
-stol(const string& str, size_t* idx, int base)
+as_integer( const string& func, const wstring& s, size_t* idx, int base )
+{
+    return as_integer_helper<long>( func, s, idx, base, wcstol );
+}
+
+template<>
+inline
+unsigned long
+as_integer( const string& func, const wstring& s, size_t* idx, int base )
+{
+    return as_integer_helper<unsigned long>( func, s, idx, base, wcstoul );
+}
+
+template<>
+inline
+long long
+as_integer( const string& func, const wstring& s, size_t* idx, int base )
+{
+    return as_integer_helper<long long>( func, s, idx, base, wcstoll );
+}
+
+template<>
+inline
+unsigned long long
+as_integer( const string& func, const wstring& s, size_t* idx, int base )
+{
+    return as_integer_helper<unsigned long long>( func, s, idx, base, wcstoull );
+}
+
+// as_float
+
+template<typename V, typename S, typename F> 
+inline
+V
+as_float_helper(const string& func, const S& str, size_t* idx, F f )
 {
-    char* ptr;
-    const char* const p = str.c_str();
+    typename S::value_type* ptr;
+    const typename S::value_type* const p = str.c_str();
     typename remove_reference<decltype(errno)>::type errno_save = errno;
     errno = 0;
-    long r = strtol(p, &ptr, base);
+    V r = f(p, &ptr);
     swap(errno, errno_save);
-#ifndef _LIBCPP_NO_EXCEPTIONS
     if (errno_save == ERANGE)
-        throw out_of_range("stol: out of range");
+        throw_from_string_out_of_range(func);
     if (ptr == p)
-        throw invalid_argument("stol: no conversion");
-#endif  // _LIBCPP_NO_EXCEPTIONS
+        throw_from_string_invalid_arg(func);
     if (idx)
         *idx = static_cast<size_t>(ptr - p);
     return r;
 }
 
+template<typename V, typename S>
+inline
+V as_float( const string& func, const S& s, size_t* idx = nullptr );
+
+template<>
+inline
+float
+as_float( const string& func, const string& s, size_t* idx )
+{
+    return as_float_helper<float>( func, s, idx, strtof );
+}
+
+template<>
+inline
+double
+as_float(const string& func, const string& s, size_t* idx )
+{
+    return as_float_helper<double>( func, s, idx, strtod );
+}
+
+template<>
+inline
+long double
+as_float( const string& func, const string& s, size_t* idx )
+{
+    return as_float_helper<long double>( func, s, idx, strtold );
+}
+
+template<>
+inline
+float
+as_float( const string& func, const wstring& s, size_t* idx )
+{
+    return as_float_helper<float>( func, s, idx, wcstof );
+}
+
+template<>
+inline
+double
+as_float( const string& func, const wstring& s, size_t* idx )
+{
+    return as_float_helper<double>( func, s, idx, wcstod );
+}
+
+template<>
+inline
+long double
+as_float( const string& func, const wstring& s, size_t* idx )
+{
+    return as_float_helper<long double>( func, s, idx, wcstold );
+}
+
+}  // unnamed namespace
+
+int
+stoi(const string& str, size_t* idx, int base)
+{
+    return as_integer<int>( "stoi", str, idx, base );
+}
+
+int
+stoi(const wstring& str, size_t* idx, int base)
+{
+    return as_integer<int>( "stoi", str, idx, base );
+}
+
+long
+stol(const string& str, size_t* idx, int base)
+{
+    return as_integer<long>( "stol", str, idx, base );
+}
+
 long
 stol(const wstring& str, size_t* idx, int base)
 {
-    wchar_t* ptr;
-    const wchar_t* const p = str.c_str();
-    typename remove_reference<decltype(errno)>::type errno_save = errno;
-    errno = 0;
-    long r = wcstol(p, &ptr, base);
-    swap(errno, errno_save);
-#ifndef _LIBCPP_NO_EXCEPTIONS
-    if (errno_save == ERANGE)
-        throw out_of_range("stol: out of range");
-    if (ptr == p)
-        throw invalid_argument("stol: no conversion");
-#endif  // _LIBCPP_NO_EXCEPTIONS
-    if (idx)
-        *idx = static_cast<size_t>(ptr - p);
-    return r;
+    return as_integer<long>( "stol", str, idx, base );
 }
 
 unsigned long
 stoul(const string& str, size_t* idx, int base)
 {
-    char* ptr;
-    const char* const p = str.c_str();
-    typename remove_reference<decltype(errno)>::type errno_save = errno;
-    errno = 0;
-    unsigned long r = strtoul(p, &ptr, base);
-    swap(errno, errno_save);
-#ifndef _LIBCPP_NO_EXCEPTIONS
-    if (errno_save == ERANGE)
-        throw out_of_range("stoul: out of range");
-    if (ptr == p)
-        throw invalid_argument("stoul: no conversion");
-#endif  // _LIBCPP_NO_EXCEPTIONS
-    if (idx)
-        *idx = static_cast<size_t>(ptr - p);
-    return r;
+    return as_integer<unsigned long>( "stoul", str, idx, base );
 }
 
 unsigned long
 stoul(const wstring& str, size_t* idx, int base)
 {
-    wchar_t* ptr;
-    const wchar_t* const p = str.c_str();
-    typename remove_reference<decltype(errno)>::type errno_save = errno;
-    errno = 0;
-    unsigned long r = wcstoul(p, &ptr, base);
-    swap(errno, errno_save);
-#ifndef _LIBCPP_NO_EXCEPTIONS
-    if (errno_save == ERANGE)
-        throw out_of_range("stoul: out of range");
-    if (ptr == p)
-        throw invalid_argument("stoul: no conversion");
-#endif  // _LIBCPP_NO_EXCEPTIONS
-    if (idx)
-        *idx = static_cast<size_t>(ptr - p);
-    return r;
+    return as_integer<unsigned long>( "stoul", str, idx, base );
 }
 
 long long
 stoll(const string& str, size_t* idx, int base)
 {
-    char* ptr;
-    const char* const p = str.c_str();
-    typename remove_reference<decltype(errno)>::type errno_save = errno;
-    errno = 0;
-    long long r = strtoll(p, &ptr, base);
-    swap(errno, errno_save);
-#ifndef _LIBCPP_NO_EXCEPTIONS
-    if (errno_save == ERANGE)
-        throw out_of_range("stoll: out of range");
-    if (ptr == p)
-        throw invalid_argument("stoll: no conversion");
-#endif  // _LIBCPP_NO_EXCEPTIONS
-    if (idx)
-        *idx = static_cast<size_t>(ptr - p);
-    return r;
+    return as_integer<long long>( "stoll", str, idx, base );
 }
 
 long long
 stoll(const wstring& str, size_t* idx, int base)
 {
-    wchar_t* ptr;
-    const wchar_t* const p = str.c_str();
-    typename remove_reference<decltype(errno)>::type errno_save = errno;
-    errno = 0;
-    long long r = wcstoll(p, &ptr, base);
-    swap(errno, errno_save);
-#ifndef _LIBCPP_NO_EXCEPTIONS
-    if (errno_save == ERANGE)
-        throw out_of_range("stoll: out of range");
-    if (ptr == p)
-        throw invalid_argument("stoll: no conversion");
-#endif  // _LIBCPP_NO_EXCEPTIONS
-    if (idx)
-        *idx = static_cast<size_t>(ptr - p);
-    return r;
+    return as_integer<long long>( "stoll", str, idx, base );
 }
 
 unsigned long long
 stoull(const string& str, size_t* idx, int base)
 {
-    char* ptr;
-    const char* const p = str.c_str();
-    typename remove_reference<decltype(errno)>::type errno_save = errno;
-    errno = 0;
-    unsigned long long r = strtoull(p, &ptr, base);
-    swap(errno, errno_save);
-#ifndef _LIBCPP_NO_EXCEPTIONS
-    if (errno_save == ERANGE)
-        throw out_of_range("stoull: out of range");
-    if (ptr == p)
-        throw invalid_argument("stoull: no conversion");
-#endif  // _LIBCPP_NO_EXCEPTIONS
-    if (idx)
-        *idx = static_cast<size_t>(ptr - p);
-    return r;
+    return as_integer<unsigned long long>( "stoull", str, idx, base );
 }
 
 unsigned long long
 stoull(const wstring& str, size_t* idx, int base)
 {
-    wchar_t* ptr;
-    const wchar_t* const p = str.c_str();
-    typename remove_reference<decltype(errno)>::type errno_save = errno;
-    errno = 0;
-    unsigned long long r = wcstoull(p, &ptr, base);
-    swap(errno, errno_save);
-#ifndef _LIBCPP_NO_EXCEPTIONS
-    if (errno_save == ERANGE)
-        throw out_of_range("stoull: out of range");
-    if (ptr == p)
-        throw invalid_argument("stoull: no conversion");
-#endif  // _LIBCPP_NO_EXCEPTIONS
-    if (idx)
-        *idx = static_cast<size_t>(ptr - p);
-    return r;
+    return as_integer<unsigned long long>( "stoull", str, idx, base );
 }
 
 float
 stof(const string& str, size_t* idx)
 {
-    char* ptr;
-    const char* const p = str.c_str();
-    typename remove_reference<decltype(errno)>::type errno_save = errno;
-    errno = 0;
-    float r = strtof(p, &ptr);
-    swap(errno, errno_save);
-#ifndef _LIBCPP_NO_EXCEPTIONS
-    if (errno_save == ERANGE)
-        throw out_of_range("stof: out of range");
-    if (ptr == p)
-        throw invalid_argument("stof: no conversion");
-#endif  // _LIBCPP_NO_EXCEPTIONS
-    if (idx)
-        *idx = static_cast<size_t>(ptr - p);
-    return r;
+    return as_float<float>( "stof", str, idx );
 }
 
 float
 stof(const wstring& str, size_t* idx)
 {
-    wchar_t* ptr;
-    const wchar_t* const p = str.c_str();
-    typename remove_reference<decltype(errno)>::type errno_save = errno;
-    errno = 0;
-    float r = wcstof(p, &ptr);
-    swap(errno, errno_save);
-#ifndef _LIBCPP_NO_EXCEPTIONS
-    if (errno_save == ERANGE)
-        throw out_of_range("stof: out of range");
-    if (ptr == p)
-        throw invalid_argument("stof: no conversion");
-#endif  // _LIBCPP_NO_EXCEPTIONS
-    if (idx)
-        *idx = static_cast<size_t>(ptr - p);
-    return r;
+    return as_float<float>( "stof", str, idx );
 }
 
 double
 stod(const string& str, size_t* idx)
 {
-    char* ptr;
-    const char* const p = str.c_str();
-    typename remove_reference<decltype(errno)>::type errno_save = errno;
-    errno = 0;
-    double r = strtod(p, &ptr);
-    swap(errno, errno_save);
-#ifndef _LIBCPP_NO_EXCEPTIONS
-    if (errno_save == ERANGE)
-        throw out_of_range("stod: out of range");
-    if (ptr == p)
-        throw invalid_argument("stod: no conversion");
-#endif  // _LIBCPP_NO_EXCEPTIONS
-    if (idx)
-        *idx = static_cast<size_t>(ptr - p);
-    return r;
+    return as_float<double>( "stod", str, idx );
 }
 
 double
 stod(const wstring& str, size_t* idx)
 {
-    wchar_t* ptr;
-    const wchar_t* const p = str.c_str();
-    typename remove_reference<decltype(errno)>::type errno_save = errno;
-    errno = 0;
-    double r = wcstod(p, &ptr);
-    swap(errno, errno_save);
-#ifndef _LIBCPP_NO_EXCEPTIONS
-    if (errno_save == ERANGE)
-        throw out_of_range("stod: out of range");
-    if (ptr == p)
-        throw invalid_argument("stod: no conversion");
-#endif  // _LIBCPP_NO_EXCEPTIONS
-    if (idx)
-        *idx = static_cast<size_t>(ptr - p);
-    return r;
+    return as_float<double>( "stod", str, idx );
 }
 
 long double
 stold(const string& str, size_t* idx)
 {
-    char* ptr;
-    const char* const p = str.c_str();
-    typename remove_reference<decltype(errno)>::type errno_save = errno;
-    errno = 0;
-    long double r = strtold(p, &ptr);
-    swap(errno, errno_save);
-#ifndef _LIBCPP_NO_EXCEPTIONS
-    if (errno_save == ERANGE)
-        throw out_of_range("stold: out of range");
-    if (ptr == p)
-        throw invalid_argument("stold: no conversion");
-#endif  // _LIBCPP_NO_EXCEPTIONS
-    if (idx)
-        *idx = static_cast<size_t>(ptr - p);
-    return r;
+    return as_float<long double>( "stold", str, idx );
 }
 
 long double
 stold(const wstring& str, size_t* idx)
 {
-    wchar_t* ptr;
-    const wchar_t* const p = str.c_str();
-    typename remove_reference<decltype(errno)>::type errno_save = errno;
-    errno = 0;
-    long double r = wcstold(p, &ptr);
-    swap(errno, errno_save);
-#ifndef _LIBCPP_NO_EXCEPTIONS
-    if (errno_save == ERANGE)
-        throw out_of_range("stold: out of range");
-    if (ptr == p)
-        throw invalid_argument("stold: no conversion");
-#endif  // _LIBCPP_NO_EXCEPTIONS
-    if (idx)
-        *idx = static_cast<size_t>(ptr - p);
-    return r;
+    return as_float<long double>( "stold", str, idx );
 }
 
-string to_string(int val)
+// to_string
+
+namespace
+{
+
+// as_string
+
+template<typename S, typename P, typename V >
+inline
+S
+as_string(P sprintf_like, S s, const typename S::value_type* fmt, V a)
 {
-    string s;
-    s.resize(s.capacity());
+    typedef typename S::size_type size_type;
+    size_type available = s.size();
     while (true)
     {
-        size_t n2 = static_cast<size_t>(snprintf(&s[0], s.size()+1, "%d", val));
-        if (n2 <= s.size())
+        int status = sprintf_like(&s[0], available + 1, fmt, a);
+        if ( status >= 0 )
         {
-            s.resize(n2);
-            break;
+            size_type used = static_cast<size_type>(status);
+            if ( used <= available )
+            {
+                s.resize( used );
+                break;
+            }
+            available = used; // Assume this is advice of how much space we need.
         }
-        s.resize(n2);
+        else
+            available = available * 2 + 1;
+        s.resize(available);
     }
     return s;
 }
 
-string to_string(unsigned val)
+template <class S, class V, bool = is_floating_point<V>::value>
+struct initial_string;
+
+template <class V, bool b>
+struct initial_string<string, V, b>
 {
-    string s;
-    s.resize(s.capacity());
-    while (true)
+    string
+    operator()() const
     {
-        size_t n2 = static_cast<size_t>(snprintf(&s[0], s.size()+1, "%u", val));
-        if (n2 <= s.size())
-        {
-            s.resize(n2);
-            break;
-        }
-        s.resize(n2);
+        string s;
+        s.resize(s.capacity());
+        return s;
     }
-    return s;
-}
+};
 
-string to_string(long val)
+template <class V>
+struct initial_string<wstring, V, false>
 {
-    string s;
-    s.resize(s.capacity());
-    while (true)
+    wstring
+    operator()() const
     {
-        size_t n2 = static_cast<size_t>(snprintf(&s[0], s.size()+1, "%ld", val));
-        if (n2 <= s.size())
-        {
-            s.resize(n2);
-            break;
-        }
-        s.resize(n2);
+        const size_t n = (numeric_limits<unsigned long long>::digits / 3)
+          + ((numeric_limits<unsigned long long>::digits % 3) != 0)
+          + 1;
+        wstring s(n, wchar_t());
+        s.resize(s.capacity());
+        return s;
     }
-    return s;
-}
+};
 
-string to_string(unsigned long val)
+template <class V>
+struct initial_string<wstring, V, true>
 {
-    string s;
-    s.resize(s.capacity());
-    while (true)
+    wstring
+    operator()() const
     {
-        size_t n2 = static_cast<size_t>(snprintf(&s[0], s.size()+1, "%lu", val));
-        if (n2 <= s.size())
-        {
-            s.resize(n2);
-            break;
-        }
-        s.resize(n2);
+        wstring s(20, wchar_t());
+        s.resize(s.capacity());
+        return s;
     }
-    return s;
+};
+
+typedef int (*wide_printf)(wchar_t* __restrict, size_t, const wchar_t*__restrict, ...);
+
+inline
+wide_printf
+get_swprintf()
+{
+#ifndef _WIN32
+    return swprintf;
+#else
+    return static_cast<int (__cdecl*)(wchar_t* __restrict, size_t, const wchar_t*__restrict, ...)>(swprintf);
+#endif
+}
+
+}  // unnamed namespace
+
+string to_string(int val)
+{
+    return as_string(snprintf, initial_string<string, int>()(), "%d", val);
+}
+
+string to_string(unsigned val)
+{
+    return as_string(snprintf, initial_string<string, unsigned>()(), "%u", val);
+}
+
+string to_string(long val)
+{
+    return as_string(snprintf, initial_string<string, long>()(), "%ld", val);
+}
+
+string to_string(unsigned long val)
+{
+    return as_string(snprintf, initial_string<string, unsigned long>()(), "%lu", val);
 }
 
 string to_string(long long val)
 {
-    string s;
-    s.resize(s.capacity());
-    while (true)
-    {
-        size_t n2 = static_cast<size_t>(snprintf(&s[0], s.size()+1, "%lld", val));
-        if (n2 <= s.size())
-        {
-            s.resize(n2);
-            break;
-        }
-        s.resize(n2);
-    }
-    return s;
+    return as_string(snprintf, initial_string<string, long long>()(), "%lld", val);
 }
 
 string to_string(unsigned long long val)
 {
-    string s;
-    s.resize(s.capacity());
-    while (true)
-    {
-        size_t n2 = static_cast<size_t>(snprintf(&s[0], s.size()+1, "%llu", val));
-        if (n2 <= s.size())
-        {
-            s.resize(n2);
-            break;
-        }
-        s.resize(n2);
-    }
-    return s;
+    return as_string(snprintf, initial_string<string, unsigned long long>()(), "%llu", val);
 }
 
 string to_string(float val)
 {
-    string s;
-    s.resize(s.capacity());
-    while (true)
-    {
-        size_t n2 = static_cast<size_t>(snprintf(&s[0], s.size()+1, "%f", val));
-        if (n2 <= s.size())
-        {
-            s.resize(n2);
-            break;
-        }
-        s.resize(n2);
-    }
-    return s;
+    return as_string(snprintf, initial_string<string, float>()(), "%f", val);
 }
 
 string to_string(double val)
 {
-    string s;
-    s.resize(s.capacity());
-    while (true)
-    {
-        size_t n2 = static_cast<size_t>(snprintf(&s[0], s.size()+1, "%f", val));
-        if (n2 <= s.size())
-        {
-            s.resize(n2);
-            break;
-        }
-        s.resize(n2);
-    }
-    return s;
+    return as_string(snprintf, initial_string<string, double>()(), "%f", val);
 }
 
 string to_string(long double val)
 {
-    string s;
-    s.resize(s.capacity());
-    while (true)
-    {
-        size_t n2 = static_cast<size_t>(snprintf(&s[0], s.size()+1, "%Lf", val));
-        if (n2 <= s.size())
-        {
-            s.resize(n2);
-            break;
-        }
-        s.resize(n2);
-    }
-    return s;
+    return as_string(snprintf, initial_string<string, long double>()(), "%Lf", val);
 }
 
 wstring to_wstring(int val)
 {
-    const size_t n = (numeric_limits<int>::digits / 3)
-          + ((numeric_limits<int>::digits % 3) != 0)
-          + 1;
-    wstring s(n, wchar_t());
-    s.resize(s.capacity());
-    while (true)
-    {
-        int n2 = swprintf(&s[0], s.size()+1, L"%d", val);
-        if (n2 > 0)
-        {
-            s.resize(static_cast<size_t>(n2));
-            break;
-        }
-        s.resize(2*s.size());
-        s.resize(s.capacity());
-    }
-    return s;
+    return as_string(get_swprintf(), initial_string<wstring, int>()(), L"%d", val);
 }
 
 wstring to_wstring(unsigned val)
 {
-    const size_t n = (numeric_limits<unsigned>::digits / 3)
-          + ((numeric_limits<unsigned>::digits % 3) != 0)
-          + 1;
-    wstring s(n, wchar_t());
-    s.resize(s.capacity());
-    while (true)
-    {
-        int n2 = swprintf(&s[0], s.size()+1, L"%u", val);
-        if (n2 > 0)
-        {
-            s.resize(static_cast<size_t>(n2));
-            break;
-        }
-        s.resize(2*s.size());
-        s.resize(s.capacity());
-    }
-    return s;
+    return as_string(get_swprintf(), initial_string<wstring, unsigned>()(), L"%u", val);
 }
 
 wstring to_wstring(long val)
 {
-    const size_t n = (numeric_limits<long>::digits / 3)
-          + ((numeric_limits<long>::digits % 3) != 0)
-          + 1;
-    wstring s(n, wchar_t());
-    s.resize(s.capacity());
-    while (true)
-    {
-        int n2 = swprintf(&s[0], s.size()+1, L"%ld", val);
-        if (n2 > 0)
-        {
-            s.resize(static_cast<size_t>(n2));
-            break;
-        }
-        s.resize(2*s.size());
-        s.resize(s.capacity());
-    }
-    return s;
+    return as_string(get_swprintf(), initial_string<wstring, long>()(), L"%ld", val);
 }
 
 wstring to_wstring(unsigned long val)
 {
-    const size_t n = (numeric_limits<unsigned long>::digits / 3)
-          + ((numeric_limits<unsigned long>::digits % 3) != 0)
-          + 1;
-    wstring s(n, wchar_t());
-    s.resize(s.capacity());
-    while (true)
-    {
-        int n2 = swprintf(&s[0], s.size()+1, L"%lu", val);
-        if (n2 > 0)
-        {
-            s.resize(static_cast<size_t>(n2));
-            break;
-        }
-        s.resize(2*s.size());
-        s.resize(s.capacity());
-    }
-    return s;
+    return as_string(get_swprintf(), initial_string<wstring, unsigned long>()(), L"%lu", val);
 }
 
 wstring to_wstring(long long val)
 {
-    const size_t n = (numeric_limits<long long>::digits / 3)
-          + ((numeric_limits<long long>::digits % 3) != 0)
-          + 1;
-    wstring s(n, wchar_t());
-    s.resize(s.capacity());
-    while (true)
-    {
-        int n2 = swprintf(&s[0], s.size()+1, L"%lld", val);
-        if (n2 > 0)
-        {
-            s.resize(static_cast<size_t>(n2));
-            break;
-        }
-        s.resize(2*s.size());
-        s.resize(s.capacity());
-    }
-    return s;
+    return as_string(get_swprintf(), initial_string<wstring, long long>()(), L"%lld", val);
 }
 
 wstring to_wstring(unsigned long long val)
 {
-    const size_t n = (numeric_limits<unsigned long long>::digits / 3)
-          + ((numeric_limits<unsigned long long>::digits % 3) != 0)
-          + 1;
-    wstring s(n, wchar_t());
-    s.resize(s.capacity());
-    while (true)
-    {
-        int n2 = swprintf(&s[0], s.size()+1, L"%llu", val);
-        if (n2 > 0)
-        {
-            s.resize(static_cast<size_t>(n2));
-            break;
-        }
-        s.resize(2*s.size());
-        s.resize(s.capacity());
-    }
-    return s;
+    return as_string(get_swprintf(), initial_string<wstring, unsigned long long>()(), L"%llu", val);
 }
 
 wstring to_wstring(float val)
 {
-    const size_t n = 20;
-    wstring s(n, wchar_t());
-    s.resize(s.capacity());
-    while (true)
-    {
-        int n2 = swprintf(&s[0], s.size()+1, L"%f", val);
-        if (n2 > 0)
-        {
-            s.resize(static_cast<size_t>(n2));
-            break;
-        }
-        s.resize(2*s.size());
-        s.resize(s.capacity());
-    }
-    return s;
+    return as_string(get_swprintf(), initial_string<wstring, float>()(), L"%f", val);
 }
 
 wstring to_wstring(double val)
 {
-    const size_t n = 20;
-    wstring s(n, wchar_t());
-    s.resize(s.capacity());
-    while (true)
-    {
-        int n2 = swprintf(&s[0], s.size()+1, L"%f", val);
-        if (n2 > 0)
-        {
-            s.resize(static_cast<size_t>(n2));
-            break;
-        }
-        s.resize(2*s.size());
-        s.resize(s.capacity());
-    }
-    return s;
+    return as_string(get_swprintf(), initial_string<wstring, double>()(), L"%f", val);
 }
 
 wstring to_wstring(long double val)
 {
-    const size_t n = 20;
-    wstring s(n, wchar_t());
-    s.resize(s.capacity());
-    while (true)
-    {
-        int n2 = swprintf(&s[0], s.size()+1, L"%Lf", val);
-        if (n2 > 0)
-        {
-            s.resize(static_cast<size_t>(n2));
-            break;
-        }
-        s.resize(2*s.size());
-        s.resize(s.capacity());
-    }
-    return s;
+    return as_string(get_swprintf(), initial_string<wstring, long double>()(), L"%Lf", val);
 }
-
 _LIBCPP_END_NAMESPACE_STD
diff --git a/src/thread.cpp b/src/thread.cpp
index c6f6748f01b3..1fd8bb047c89 100644
--- a/src/thread.cpp
+++ b/src/thread.cpp
@@ -16,11 +16,17 @@
 #if !defined(_WIN32)
 #if !defined(__sun__) && !defined(__linux__)
 #include <sys/sysctl.h>
-#else
-#include <unistd.h>
 #endif // !__sun__ && !__linux__
+#include <unistd.h>
 #endif // !_WIN32
 
+#if defined(__NetBSD__)
+#pragma weak pthread_create // Do not create libpthread dependency
+#endif
+#if defined(_WIN32)
+#include <windows.h>
+#endif
+
 _LIBCPP_BEGIN_NAMESPACE_STD
 
 thread::~thread()
@@ -67,7 +73,7 @@ thread::hardware_concurrency() _NOEXCEPT
     std::size_t s = sizeof(n);
     sysctl(mib, 2, &n, &s, 0, 0);
     return n;
-#elif (defined(_POSIX_C_SOURCE) && (_POSIX_C_SOURCE >= 200112L) && defined(_SC_NPROCESSORS_ONLN)) || defined(EMSCRIPTEN)
+#elif defined(_SC_NPROCESSORS_ONLN)
     long result = sysconf(_SC_NPROCESSORS_ONLN);
     // sysconf returns -1 if the name is invalid, the option does not exist or
     // does not have a definite limit.
@@ -76,9 +82,14 @@ thread::hardware_concurrency() _NOEXCEPT
     if (result < 0)
         return 0;
     return static_cast<unsigned>(result);
+#elif defined(_WIN32)
+    SYSTEM_INFO info;
+    GetSystemInfo(&info);
+    return info.dwNumberOfProcessors;
 #else  // defined(CTL_HW) && defined(HW_NCPU)
     // TODO: grovel through /proc or check cpuid on x86 and similar
     // instructions on other architectures.
+#warning hardware_concurrency not yet implemented
     return 0;  // Means not computable [thread.thread.static]
 #endif  // defined(CTL_HW) && defined(HW_NCPU)
 }