Commit 0d4e223ab5

Andrew Kelley <andrew@ziglang.org>
2023-03-17 20:21:27
update libcxx to LLVM 16.0.0-rc4
1 parent cef9aaa
lib/libcxx/include/__algorithm/ranges_binary_search.h
@@ -36,7 +36,7 @@ struct __fn {
   _LIBCPP_NODISCARD_EXT _LIBCPP_HIDE_FROM_ABI constexpr
   bool operator()(_Iter __first, _Sent __last, const _Type& __value, _Comp __comp = {}, _Proj __proj = {}) const {
     auto __ret = std::__lower_bound_impl<_RangeAlgPolicy>(__first, __last, __value, __comp, __proj);
-    return __ret != __last && !std::invoke(__comp, __value, std::invoke(__proj, *__first));
+    return __ret != __last && !std::invoke(__comp, __value, std::invoke(__proj, *__ret));
   }
 
   template <forward_range _Range, class _Type, class _Proj = identity,
@@ -46,7 +46,7 @@ struct __fn {
     auto __first = ranges::begin(__r);
     auto __last = ranges::end(__r);
     auto __ret = std::__lower_bound_impl<_RangeAlgPolicy>(__first, __last, __value, __comp, __proj);
-    return __ret != __last && !std::invoke(__comp, __value, std::invoke(__proj, *__first));
+    return __ret != __last && !std::invoke(__comp, __value, std::invoke(__proj, *__ret));
   }
 };
 } // namespace __binary_search
lib/libcxx/include/__format/concepts.h
@@ -66,9 +66,8 @@ concept formattable = __formattable<_Tp, _CharT>;
 // TODO FMT Add a test to validate we fail when using that concept after P2165
 // has been implemented.
 template <class _Tp>
-concept __fmt_pair_like = __is_specialization_v<_Tp, pair> ||
-                          // Use a requires since tuple_size_v may fail to instantiate,
-                          (__is_specialization_v<_Tp, tuple> && requires { tuple_size_v<_Tp> == 2; });
+concept __fmt_pair_like =
+    __is_specialization_v<_Tp, pair> || (__is_specialization_v<_Tp, tuple> && tuple_size_v<_Tp> == 2);
 
 #  endif //_LIBCPP_STD_VER > 20
 #endif //_LIBCPP_STD_VER > 17
lib/libcxx/include/__format/format_functions.h
@@ -258,10 +258,12 @@ __handle_replacement_field(const _CharT* __begin, const _CharT* __end,
 
   if constexpr (same_as<_Ctx, __compile_time_basic_format_context<_CharT>>) {
     __arg_t __type = __ctx.arg(__r.__value);
-    if (__type == __arg_t::__handle)
+    if (__type == __arg_t::__none)
+      std::__throw_format_error("Argument index out of bounds");
+    else if (__type == __arg_t::__handle)
       __ctx.__handle(__r.__value).__parse(__parse_ctx);
-    else
-        __format::__compile_time_visit_format_arg(__parse_ctx, __ctx, __type);
+    else if (__parse)
+      __format::__compile_time_visit_format_arg(__parse_ctx, __ctx, __type);
   } else
     _VSTD::__visit_format_arg(
         [&](auto __arg) {
lib/libcxx/include/__format/formatter_floating_point.h
@@ -404,7 +404,6 @@ _LIBCPP_HIDE_FROM_ABI __float_result __format_buffer_general_lower_case(__float_
       // In fixed mode the algorithm truncates trailing spaces and possibly the
       // radix point. There's no good guess for the position of the radix point
       // therefore scan the output after the first digit.
-
       __result.__radix_point = _VSTD::find(__first, __result.__last, '.');
     }
   }
@@ -665,7 +664,7 @@ __format_floating_point(_Tp __value, auto& __ctx, __format_spec::__parsed_specif
       if (__result.__exponent == __result.__last)
         // if P > X >= -4, the conversion is with style f or F and precision P - 1 - X.
         // By including the radix point it calculates P - (1 + X)
-        __p -= __result.__radix_point - __buffer.begin();
+        __p -= __result.__radix_point - __result.__integral;
       else
         // otherwise, the conversion is with style e or E and precision P - 1.
         --__p;
lib/libcxx/include/__functional/function.h
@@ -268,10 +268,10 @@ public:
     virtual void destroy() _NOEXCEPT = 0;
     virtual void destroy_deallocate() _NOEXCEPT = 0;
     virtual _Rp operator()(_ArgTypes&& ...) = 0;
-#ifndef _LIBCPP_NO_RTTI
+#ifndef _LIBCPP_HAS_NO_RTTI
     virtual const void* target(const type_info&) const _NOEXCEPT = 0;
     virtual const std::type_info& target_type() const _NOEXCEPT = 0;
-#endif // _LIBCPP_NO_RTTI
+#endif // _LIBCPP_HAS_NO_RTTI
 };
 
 // __func implements __base for a given functor type.
@@ -305,10 +305,10 @@ public:
     virtual void destroy() _NOEXCEPT;
     virtual void destroy_deallocate() _NOEXCEPT;
     virtual _Rp operator()(_ArgTypes&&... __arg);
-#ifndef _LIBCPP_NO_RTTI
+#ifndef _LIBCPP_HAS_NO_RTTI
     virtual const void* target(const type_info&) const _NOEXCEPT;
     virtual const std::type_info& target_type() const _NOEXCEPT;
-#endif // _LIBCPP_NO_RTTI
+#endif // _LIBCPP_HAS_NO_RTTI
 };
 
 template<class _Fp, class _Alloc, class _Rp, class ..._ArgTypes>
@@ -356,7 +356,7 @@ __func<_Fp, _Alloc, _Rp(_ArgTypes...)>::operator()(_ArgTypes&& ... __arg)
     return __f_(_VSTD::forward<_ArgTypes>(__arg)...);
 }
 
-#ifndef _LIBCPP_NO_RTTI
+#ifndef _LIBCPP_HAS_NO_RTTI
 
 template<class _Fp, class _Alloc, class _Rp, class ..._ArgTypes>
 const void*
@@ -374,7 +374,7 @@ __func<_Fp, _Alloc, _Rp(_ArgTypes...)>::target_type() const _NOEXCEPT
     return typeid(_Fp);
 }
 
-#endif // _LIBCPP_NO_RTTI
+#endif // _LIBCPP_HAS_NO_RTTI
 
 // __value_func creates a value-type from a __func.
 
@@ -553,7 +553,7 @@ template <class _Rp, class... _ArgTypes> class __value_func<_Rp(_ArgTypes...)>
     _LIBCPP_INLINE_VISIBILITY
     explicit operator bool() const _NOEXCEPT { return __f_ != nullptr; }
 
-#ifndef _LIBCPP_NO_RTTI
+#ifndef _LIBCPP_HAS_NO_RTTI
     _LIBCPP_INLINE_VISIBILITY
     const std::type_info& target_type() const _NOEXCEPT
     {
@@ -569,7 +569,7 @@ template <class _Rp, class... _ArgTypes> class __value_func<_Rp(_ArgTypes...)>
             return nullptr;
         return (const _Tp*)__f_->target(typeid(_Tp));
     }
-#endif // _LIBCPP_NO_RTTI
+#endif // _LIBCPP_HAS_NO_RTTI
 };
 
 // Storage for a functor object, to be used with __policy to manage copy and
@@ -616,7 +616,7 @@ struct __policy
     {
         static const _LIBCPP_CONSTEXPR __policy __policy_ = {nullptr, nullptr,
                                                              true,
-#ifndef _LIBCPP_NO_RTTI
+#ifndef _LIBCPP_HAS_NO_RTTI
                                                              &typeid(void)
 #else
                                                              nullptr
@@ -642,7 +642,7 @@ struct __policy
     __choose_policy(/* is_small = */ false_type) {
       static const _LIBCPP_CONSTEXPR __policy __policy_ = {
           &__large_clone<_Fun>, &__large_destroy<_Fun>, false,
-#ifndef _LIBCPP_NO_RTTI
+#ifndef _LIBCPP_HAS_NO_RTTI
           &typeid(typename _Fun::_Target)
 #else
           nullptr
@@ -657,7 +657,7 @@ struct __policy
     {
         static const _LIBCPP_CONSTEXPR __policy __policy_ = {
             nullptr, nullptr, false,
-#ifndef _LIBCPP_NO_RTTI
+#ifndef _LIBCPP_HAS_NO_RTTI
             &typeid(typename _Fun::_Target)
 #else
             nullptr
@@ -861,7 +861,7 @@ template <class _Rp, class... _ArgTypes> class __policy_func<_Rp(_ArgTypes...)>
         return !__policy_->__is_null;
     }
 
-#ifndef _LIBCPP_NO_RTTI
+#ifndef _LIBCPP_HAS_NO_RTTI
     _LIBCPP_INLINE_VISIBILITY
     const std::type_info& target_type() const _NOEXCEPT
     {
@@ -878,7 +878,7 @@ template <class _Rp, class... _ArgTypes> class __policy_func<_Rp(_ArgTypes...)>
         else
             return reinterpret_cast<const _Tp*>(&__buf_.__small);
     }
-#endif // _LIBCPP_NO_RTTI
+#endif // _LIBCPP_HAS_NO_RTTI
 };
 
 #if defined(_LIBCPP_HAS_BLOCKS_RUNTIME)
@@ -945,7 +945,7 @@ public:
         return _VSTD::__invoke(__f_, _VSTD::forward<_ArgTypes>(__arg)...);
     }
 
-#ifndef _LIBCPP_NO_RTTI
+#ifndef _LIBCPP_HAS_NO_RTTI
     virtual const void* target(type_info const& __ti) const _NOEXCEPT {
         if (__ti == typeid(__func::__block_type))
             return &__f_;
@@ -955,7 +955,7 @@ public:
     virtual const std::type_info& target_type() const _NOEXCEPT {
         return typeid(__func::__block_type);
     }
-#endif // _LIBCPP_NO_RTTI
+#endif // _LIBCPP_HAS_NO_RTTI
 };
 
 #endif // _LIBCPP_HAS_EXTENSION_BLOCKS
@@ -1056,12 +1056,12 @@ public:
     // function invocation:
     _Rp operator()(_ArgTypes...) const;
 
-#ifndef _LIBCPP_NO_RTTI
+#ifndef _LIBCPP_HAS_NO_RTTI
     // function target access:
     const std::type_info& target_type() const _NOEXCEPT;
     template <typename _Tp> _Tp* target() _NOEXCEPT;
     template <typename _Tp> const _Tp* target() const _NOEXCEPT;
-#endif // _LIBCPP_NO_RTTI
+#endif // _LIBCPP_HAS_NO_RTTI
 };
 
 #if _LIBCPP_STD_VER >= 17
@@ -1156,7 +1156,7 @@ function<_Rp(_ArgTypes...)>::operator()(_ArgTypes... __arg) const
     return __f_(_VSTD::forward<_ArgTypes>(__arg)...);
 }
 
-#ifndef _LIBCPP_NO_RTTI
+#ifndef _LIBCPP_HAS_NO_RTTI
 
 template<class _Rp, class ..._ArgTypes>
 const std::type_info&
@@ -1181,7 +1181,7 @@ function<_Rp(_ArgTypes...)>::target() const _NOEXCEPT
     return __f_.template target<_Tp>();
 }
 
-#endif // _LIBCPP_NO_RTTI
+#endif // _LIBCPP_HAS_NO_RTTI
 
 template <class _Rp, class... _ArgTypes>
 inline _LIBCPP_INLINE_VISIBILITY
lib/libcxx/include/__functional/hash.h
@@ -140,7 +140,11 @@ struct __murmur2_or_cityhash<_Size, 64>
     if (__len >= 4) {
       const uint32_t __a = std::__loadword<uint32_t>(__s);
       const uint32_t __b = std::__loadword<uint32_t>(__s + __len - 4);
+#ifdef _LIBCPP_ABI_FIX_CITYHASH_IMPLEMENTATION
       return __hash_len_16(__len + (static_cast<_Size>(__a) << 3), __b);
+#else
+      return __hash_len_16(__len + (__a << 3), __b);
+#endif
     }
     if (__len > 0) {
       const unsigned char __a = static_cast<unsigned char>(__s[0]);
lib/libcxx/include/__memory/construct_at.h
@@ -83,6 +83,16 @@ _ForwardIterator __destroy(_ForwardIterator __first, _ForwardIterator __last) {
     return __first;
 }
 
+template <class _BidirectionalIterator>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20
+_BidirectionalIterator __reverse_destroy(_BidirectionalIterator __first, _BidirectionalIterator __last) {
+    while (__last != __first) {
+        --__last;
+        std::__destroy_at(std::addressof(*__last));
+    }
+    return __last;
+}
+
 #if _LIBCPP_STD_VER > 14
 
 template <class _Tp, enable_if_t<!is_array_v<_Tp>, int> = 0>
lib/libcxx/include/__memory/shared_ptr.h
@@ -219,7 +219,7 @@ public:
     __shared_ptr_pointer(_Tp __p, _Dp __d, _Alloc __a)
         :  __data_(__compressed_pair<_Tp, _Dp>(__p, _VSTD::move(__d)), _VSTD::move(__a)) {}
 
-#ifndef _LIBCPP_NO_RTTI
+#ifndef _LIBCPP_HAS_NO_RTTI
     const void* __get_deleter(const type_info&) const _NOEXCEPT override;
 #endif
 
@@ -228,7 +228,7 @@ private:
     void __on_zero_shared_weak() _NOEXCEPT override;
 };
 
-#ifndef _LIBCPP_NO_RTTI
+#ifndef _LIBCPP_HAS_NO_RTTI
 
 template <class _Tp, class _Dp, class _Alloc>
 const void*
@@ -237,7 +237,7 @@ __shared_ptr_pointer<_Tp, _Dp, _Alloc>::__get_deleter(const type_info& __t) cons
     return __t == typeid(_Dp) ? _VSTD::addressof(__data_.first().second()) : nullptr;
 }
 
-#endif // _LIBCPP_NO_RTTI
+#endif // _LIBCPP_HAS_NO_RTTI
 
 template <class _Tp, class _Dp, class _Alloc>
 void
@@ -260,7 +260,10 @@ __shared_ptr_pointer<_Tp, _Dp, _Alloc>::__on_zero_shared_weak() _NOEXCEPT
     __a.deallocate(_PTraits::pointer_to(*this), 1);
 }
 
-struct __default_initialize_tag {};
+// This tag is used to instantiate an allocator type. The various shared_ptr control blocks
+// detect that the allocator has been instantiated for this type and perform alternative
+// initialization/destruction based on that.
+struct __for_overwrite_tag {};
 
 template <class _Tp, class _Alloc>
 struct __shared_ptr_emplace
@@ -271,25 +274,20 @@ struct __shared_ptr_emplace
     explicit __shared_ptr_emplace(_Alloc __a, _Args&& ...__args)
         : __storage_(_VSTD::move(__a))
     {
-#if _LIBCPP_STD_VER > 17
-        using _TpAlloc = typename __allocator_traits_rebind<_Alloc, _Tp>::type;
-        _TpAlloc __tmp(*__get_alloc());
-        allocator_traits<_TpAlloc>::construct(__tmp, __get_elem(), _VSTD::forward<_Args>(__args)...);
+#if _LIBCPP_STD_VER >= 20
+        if constexpr (is_same_v<typename _Alloc::value_type, __for_overwrite_tag>) {
+            static_assert(sizeof...(_Args) == 0, "No argument should be provided to the control block when using _for_overwrite");
+            ::new ((void*)__get_elem()) _Tp;
+        } else {
+            using _TpAlloc = typename __allocator_traits_rebind<_Alloc, _Tp>::type;
+            _TpAlloc __tmp(*__get_alloc());
+            allocator_traits<_TpAlloc>::construct(__tmp, __get_elem(), _VSTD::forward<_Args>(__args)...);
+        }
 #else
         ::new ((void*)__get_elem()) _Tp(_VSTD::forward<_Args>(__args)...);
 #endif
     }
 
-
-#if _LIBCPP_STD_VER >= 20
-    _LIBCPP_HIDE_FROM_ABI
-    explicit __shared_ptr_emplace(__default_initialize_tag, _Alloc __a)
-        : __storage_(std::move(__a))
-    {
-        ::new ((void*)__get_elem()) _Tp;
-    }
-#endif
-
     _LIBCPP_HIDE_FROM_ABI
     _Alloc* __get_alloc() _NOEXCEPT { return __storage_.__get_alloc(); }
 
@@ -299,9 +297,13 @@ struct __shared_ptr_emplace
 private:
     void __on_zero_shared() _NOEXCEPT override {
 #if _LIBCPP_STD_VER > 17
-        using _TpAlloc = typename __allocator_traits_rebind<_Alloc, _Tp>::type;
-        _TpAlloc __tmp(*__get_alloc());
-        allocator_traits<_TpAlloc>::destroy(__tmp, __get_elem());
+        if constexpr (is_same_v<typename _Alloc::value_type, __for_overwrite_tag>) {
+            __get_elem()->~_Tp();
+        } else {
+            using _TpAlloc = typename __allocator_traits_rebind<_Alloc, _Tp>::type;
+            _TpAlloc __tmp(*__get_alloc());
+            allocator_traits<_TpAlloc>::destroy(__tmp, __get_elem());
+        }
 #else
         __get_elem()->~_Tp();
 #endif
@@ -367,13 +369,57 @@ public:
 
 template<class _Tp> class _LIBCPP_TEMPLATE_VIS enable_shared_from_this;
 
-template<class _Tp, class _Up>
+// http://eel.is/c++draft/util.sharedptr#util.smartptr.shared.general-6
+// A pointer type Y* is said to be compatible with a pointer type T*
+// when either Y* is convertible to T* or Y is U[N] and T is cv U[].
+#if _LIBCPP_STD_VER >= 17
+template <class _Yp, class _Tp>
+struct __bounded_convertible_to_unbounded : false_type {};
+
+template <class _Up, std::size_t _Np, class _Tp>
+struct __bounded_convertible_to_unbounded<_Up[_Np], _Tp>
+        : is_same<__remove_cv_t<_Tp>, _Up[]> {};
+
+template <class _Yp, class _Tp>
 struct __compatible_with
-#if _LIBCPP_STD_VER > 14
-    : is_convertible<remove_extent_t<_Tp>*, remove_extent_t<_Up>*> {};
+    : _Or<
+        is_convertible<_Yp*, _Tp*>,
+        __bounded_convertible_to_unbounded<_Yp, _Tp>
+    > {};
 #else
-    : is_convertible<_Tp*, _Up*> {};
-#endif // _LIBCPP_STD_VER > 14
+template <class _Yp, class _Tp>
+struct __compatible_with
+    : is_convertible<_Yp*, _Tp*> {};
+#endif // _LIBCPP_STD_VER >= 17
+
+// Constructors that take raw pointers have a different set of "compatible" constraints
+// http://eel.is/c++draft/util.sharedptr#util.smartptr.shared.const-9.1
+// - If T is an array type, then either T is U[N] and Y(*)[N] is convertible to T*,
+//   or T is U[] and Y(*)[] is convertible to T*.
+// - If T is not an array type, then Y* is convertible to T*.
+#if _LIBCPP_STD_VER >= 17
+template <class _Yp, class _Tp, class = void>
+struct __raw_pointer_compatible_with : _And<
+        _Not<is_array<_Tp>>,
+        is_convertible<_Yp*, _Tp*>
+        > {};
+
+template <class _Yp, class _Up, std::size_t _Np>
+struct __raw_pointer_compatible_with<_Yp, _Up[_Np], __enable_if_t<
+            is_convertible<_Yp(*)[_Np], _Up(*)[_Np]>::value> >
+        : true_type {};
+
+template <class _Yp, class _Up>
+struct __raw_pointer_compatible_with<_Yp, _Up[], __enable_if_t<
+            is_convertible<_Yp(*)[], _Up(*)[]>::value> >
+        : true_type {};
+
+#else
+template <class _Yp, class _Tp>
+struct __raw_pointer_compatible_with
+    : is_convertible<_Yp*, _Tp*> {};
+#endif // _LIBCPP_STD_VER >= 17
+
 
 template <class _Ptr, class = void>
 struct __is_deletable : false_type { };
@@ -395,12 +441,12 @@ static false_type __well_formed_deleter_test(...);
 template <class _Dp, class _Pt>
 struct __well_formed_deleter : decltype(std::__well_formed_deleter_test<_Dp, _Pt>(0)) {};
 
-template<class _Dp, class _Tp, class _Yp>
+template<class _Dp, class _Yp, class _Tp>
 struct __shared_ptr_deleter_ctor_reqs
 {
-    static const bool value = __compatible_with<_Tp, _Yp>::value &&
+    static const bool value = __raw_pointer_compatible_with<_Yp, _Tp>::value &&
                               is_move_constructible<_Dp>::value &&
-                              __well_formed_deleter<_Dp, _Tp*>::value;
+                              __well_formed_deleter<_Dp, _Yp*>::value;
 };
 
 #if defined(_LIBCPP_ABI_ENABLE_SHARED_PTR_TRIVIAL_ABI)
@@ -439,7 +485,7 @@ public:
 
     template<class _Yp, class = __enable_if_t<
         _And<
-            __compatible_with<_Yp, _Tp>
+            __raw_pointer_compatible_with<_Yp, _Tp>
             // In C++03 we get errors when trying to do SFINAE with the
             // delete operator, so we always pretend that it's deletable.
             // The same happens on GCC.
@@ -457,7 +503,7 @@ public:
         __enable_weak_this(__p, __p);
     }
 
-    template<class _Yp, class _Dp, class = __enable_if_t<__shared_ptr_deleter_ctor_reqs<_Dp, _Yp, element_type>::value> >
+    template<class _Yp, class _Dp, class = __enable_if_t<__shared_ptr_deleter_ctor_reqs<_Dp, _Yp, _Tp>::value> >
     _LIBCPP_HIDE_FROM_ABI
     shared_ptr(_Yp* __p, _Dp __d)
         : __ptr_(__p)
@@ -484,7 +530,7 @@ public:
 #endif // _LIBCPP_NO_EXCEPTIONS
     }
 
-    template<class _Yp, class _Dp, class _Alloc, class = __enable_if_t<__shared_ptr_deleter_ctor_reqs<_Dp, _Yp, element_type>::value> >
+    template<class _Yp, class _Dp, class _Alloc, class = __enable_if_t<__shared_ptr_deleter_ctor_reqs<_Dp, _Yp, _Tp>::value> >
     _LIBCPP_HIDE_FROM_ABI
     shared_ptr(_Yp* __p, _Dp __d, _Alloc __a)
         : __ptr_(__p)
@@ -646,6 +692,7 @@ public:
 
     template <class _Yp, class _Dp, class = __enable_if_t<
         !is_lvalue_reference<_Dp>::value &&
+         __compatible_with<_Yp, _Tp>::value &&
          is_convertible<typename unique_ptr<_Yp, _Dp>::pointer, element_type*>::value
     > >
     _LIBCPP_HIDE_FROM_ABI
@@ -668,6 +715,7 @@ public:
 
     template <class _Yp, class _Dp, class = void, class = __enable_if_t<
         is_lvalue_reference<_Dp>::value &&
+         __compatible_with<_Yp, _Tp>::value &&
         is_convertible<typename unique_ptr<_Yp, _Dp>::pointer, element_type*>::value
     > >
     _LIBCPP_HIDE_FROM_ABI
@@ -740,9 +788,10 @@ public:
     }
 #endif
 
-    template <class _Yp, class _Dp, class = __enable_if_t<
-        is_convertible<typename unique_ptr<_Yp, _Dp>::pointer, element_type*>::value
-    > >
+    template <class _Yp, class _Dp, class = __enable_if_t<_And<
+        __compatible_with<_Yp, _Tp>,
+        is_convertible<typename unique_ptr<_Yp, _Dp>::pointer, element_type*>
+    >::value> >
     _LIBCPP_HIDE_FROM_ABI
     shared_ptr<_Tp>& operator=(unique_ptr<_Yp, _Dp>&& __r)
     {
@@ -764,7 +813,7 @@ public:
     }
 
     template<class _Yp, class = __enable_if_t<
-        __compatible_with<_Yp, _Tp>::value
+        __raw_pointer_compatible_with<_Yp, _Tp>::value
     > >
     _LIBCPP_HIDE_FROM_ABI
     void reset(_Yp* __p)
@@ -773,8 +822,7 @@ public:
     }
 
     template<class _Yp, class _Dp, class = __enable_if_t<
-        __compatible_with<_Yp, _Tp>::value
-    > >
+        __shared_ptr_deleter_ctor_reqs<_Dp, _Yp, _Tp>::value> >
     _LIBCPP_HIDE_FROM_ABI
     void reset(_Yp* __p, _Dp __d)
     {
@@ -782,8 +830,7 @@ public:
     }
 
     template<class _Yp, class _Dp, class _Alloc, class = __enable_if_t<
-        __compatible_with<_Yp, _Tp>::value
-    > >
+        __shared_ptr_deleter_ctor_reqs<_Dp, _Yp, _Tp>::value> >
     _LIBCPP_HIDE_FROM_ABI
     void reset(_Yp* __p, _Dp __d, _Alloc __a)
     {
@@ -858,7 +905,7 @@ public:
     }
 #endif
 
-#ifndef _LIBCPP_NO_RTTI
+#ifndef _LIBCPP_HAS_NO_RTTI
     template <class _Dp>
     _LIBCPP_HIDE_FROM_ABI
     _Dp* __get_deleter() const _NOEXCEPT
@@ -867,7 +914,7 @@ public:
                     ? const_cast<void *>(__cntrl_->__get_deleter(typeid(_Dp)))
                       : nullptr);
     }
-#endif // _LIBCPP_NO_RTTI
+#endif // _LIBCPP_HAS_NO_RTTI
 
     template<class _Yp, class _CntrlBlk>
     _LIBCPP_HIDE_FROM_ABI
@@ -963,12 +1010,9 @@ template<class _Tp, class _Alloc, __enable_if_t<!is_array<_Tp>::value, int> = 0>
 _LIBCPP_HIDE_FROM_ABI
 shared_ptr<_Tp> allocate_shared_for_overwrite(const _Alloc& __a)
 {
-    using _ControlBlock = __shared_ptr_emplace<_Tp, _Alloc>;
-    using _ControlBlockAllocator = typename __allocator_traits_rebind<_Alloc, _ControlBlock>::type;
-    __allocation_guard<_ControlBlockAllocator> __guard(__a, 1);
-    ::new ((void*)_VSTD::addressof(*__guard.__get())) _ControlBlock(__default_initialize_tag{}, __a);
-    auto __control_block = __guard.__release_ptr();
-    return shared_ptr<_Tp>::__create_with_control_block((*__control_block).__get_elem(), _VSTD::addressof(*__control_block));
+    using _ForOverwriteAllocator = __allocator_traits_rebind_t<_Alloc, __for_overwrite_tag>;
+    _ForOverwriteAllocator __alloc(__a);
+    return std::allocate_shared<_Tp>(__alloc);
 }
 
 template<class _Tp, __enable_if_t<!is_array<_Tp>::value, int> = 0>
@@ -1000,26 +1044,25 @@ struct __unbounded_array_control_block<_Tp[], _Alloc> : __shared_weak_count
     explicit __unbounded_array_control_block(_Alloc const& __alloc, size_t __count, _Tp const& __arg)
         : __alloc_(__alloc), __count_(__count)
     {
-        std::__uninitialized_allocator_fill_n(__alloc_, std::begin(__data_), __count_, __arg);
+        std::__uninitialized_allocator_fill_n_multidimensional(__alloc_, std::begin(__data_), __count_, __arg);
     }
 
     _LIBCPP_HIDE_FROM_ABI
     explicit __unbounded_array_control_block(_Alloc const& __alloc, size_t __count)
         : __alloc_(__alloc), __count_(__count)
     {
-        std::__uninitialized_allocator_value_construct_n(__alloc_, std::begin(__data_), __count_);
-    }
-
 #if _LIBCPP_STD_VER >= 20
-    _LIBCPP_HIDE_FROM_ABI
-    explicit __unbounded_array_control_block(_Alloc const& __alloc, size_t __count, __default_initialize_tag)
-        : __alloc_(__alloc), __count_(__count)
-    {
-        // We are purposefully not using an allocator-aware default construction because the spec says so.
-        // There's currently no way of expressing default initialization in an allocator-aware manner anyway.
-        std::uninitialized_default_construct_n(std::begin(__data_), __count_);
-    }
+        if constexpr (is_same_v<typename _Alloc::value_type, __for_overwrite_tag>) {
+            // We are purposefully not using an allocator-aware default construction because the spec says so.
+            // There's currently no way of expressing default initialization in an allocator-aware manner anyway.
+            std::uninitialized_default_construct_n(std::begin(__data_), __count_);
+        } else {
+            std::__uninitialized_allocator_value_construct_n_multidimensional(__alloc_, std::begin(__data_), __count_);
+        }
+#else
+        std::__uninitialized_allocator_value_construct_n_multidimensional(__alloc_, std::begin(__data_), __count_);
 #endif
+    }
 
     // Returns the number of bytes required to store a control block followed by the given number
     // of elements of _Tp, with the whole storage being aligned to a multiple of _Tp's alignment.
@@ -1042,8 +1085,17 @@ struct __unbounded_array_control_block<_Tp[], _Alloc> : __shared_weak_count
 
 private:
     void __on_zero_shared() _NOEXCEPT override {
+#if _LIBCPP_STD_VER >= 20
+        if constexpr (is_same_v<typename _Alloc::value_type, __for_overwrite_tag>) {
+            std::__reverse_destroy(__data_, __data_ + __count_);
+        } else {
+            __allocator_traits_rebind_t<_Alloc, _Tp> __value_alloc(__alloc_);
+            std::__allocator_destroy_multidimensional(__value_alloc, __data_, __data_ + __count_);
+        }
+#else
         __allocator_traits_rebind_t<_Alloc, _Tp> __value_alloc(__alloc_);
         std::__allocator_destroy_multidimensional(__value_alloc, __data_, __data_ + __count_);
+#endif
     }
 
     void __on_zero_shared_weak() _NOEXCEPT override {
@@ -1096,30 +1148,40 @@ struct __bounded_array_control_block<_Tp[_Count], _Alloc>
 
     _LIBCPP_HIDE_FROM_ABI
     explicit __bounded_array_control_block(_Alloc const& __alloc, _Tp const& __arg) : __alloc_(__alloc) {
-        std::__uninitialized_allocator_fill_n(__alloc_, std::addressof(__data_[0]), _Count, __arg);
+        std::__uninitialized_allocator_fill_n_multidimensional(__alloc_, std::addressof(__data_[0]), _Count, __arg);
     }
 
     _LIBCPP_HIDE_FROM_ABI
     explicit __bounded_array_control_block(_Alloc const& __alloc) : __alloc_(__alloc) {
-        std::__uninitialized_allocator_value_construct_n(__alloc_, std::addressof(__data_[0]), _Count);
-    }
-
 #if _LIBCPP_STD_VER >= 20
-    _LIBCPP_HIDE_FROM_ABI
-    explicit __bounded_array_control_block(_Alloc const& __alloc, __default_initialize_tag) : __alloc_(__alloc) {
-        // We are purposefully not using an allocator-aware default construction because the spec says so.
-        // There's currently no way of expressing default initialization in an allocator-aware manner anyway.
-        std::uninitialized_default_construct_n(std::addressof(__data_[0]), _Count);
-    }
+        if constexpr (is_same_v<typename _Alloc::value_type, __for_overwrite_tag>) {
+            // We are purposefully not using an allocator-aware default construction because the spec says so.
+            // There's currently no way of expressing default initialization in an allocator-aware manner anyway.
+            std::uninitialized_default_construct_n(std::addressof(__data_[0]), _Count);
+        } else {
+            std::__uninitialized_allocator_value_construct_n_multidimensional(__alloc_, std::addressof(__data_[0]), _Count);
+        }
+#else
+        std::__uninitialized_allocator_value_construct_n_multidimensional(__alloc_, std::addressof(__data_[0]), _Count);
 #endif
+    }
 
     _LIBCPP_HIDE_FROM_ABI_VIRTUAL
     ~__bounded_array_control_block() override { } // can't be `= default` because of the sometimes-non-trivial union member __data_
 
 private:
     void __on_zero_shared() _NOEXCEPT override {
+#if _LIBCPP_STD_VER >= 20
+        if constexpr (is_same_v<typename _Alloc::value_type, __for_overwrite_tag>) {
+            std::__reverse_destroy(__data_, __data_ + _Count);
+        } else {
+            __allocator_traits_rebind_t<_Alloc, _Tp> __value_alloc(__alloc_);
+            std::__allocator_destroy_multidimensional(__value_alloc, __data_, __data_ + _Count);
+        }
+#else
         __allocator_traits_rebind_t<_Alloc, _Tp> __value_alloc(__alloc_);
         std::__allocator_destroy_multidimensional(__value_alloc, __data_, __data_ + _Count);
+#endif
     }
 
     void __on_zero_shared_weak() _NOEXCEPT override {
@@ -1175,7 +1237,9 @@ template<class _Tp, class _Alloc, __enable_if_t<is_bounded_array<_Tp>::value, in
 _LIBCPP_HIDE_FROM_ABI
 shared_ptr<_Tp> allocate_shared_for_overwrite(const _Alloc& __a)
 {
-    return std::__allocate_shared_bounded_array<_Tp>(__a, __default_initialize_tag{});
+    using _ForOverwriteAllocator = __allocator_traits_rebind_t<_Alloc, __for_overwrite_tag>;
+    _ForOverwriteAllocator __alloc(__a);
+    return std::__allocate_shared_bounded_array<_Tp>(__alloc);
 }
 
 template<class _Tp, class = __enable_if_t<is_bounded_array<_Tp>::value>>
@@ -1196,7 +1260,7 @@ template<class _Tp, __enable_if_t<is_bounded_array<_Tp>::value, int> = 0>
 _LIBCPP_HIDE_FROM_ABI
 shared_ptr<_Tp> make_shared_for_overwrite()
 {
-    return std::__allocate_shared_bounded_array<_Tp>(allocator<_Tp>(), __default_initialize_tag{});
+    return std::__allocate_shared_bounded_array<_Tp>(allocator<__for_overwrite_tag>());
 }
 
 // unbounded array variants
@@ -1218,7 +1282,9 @@ template<class _Tp, class _Alloc, __enable_if_t<is_unbounded_array<_Tp>::value,
 _LIBCPP_HIDE_FROM_ABI
 shared_ptr<_Tp> allocate_shared_for_overwrite(const _Alloc& __a, size_t __n)
 {
-    return std::__allocate_shared_unbounded_array<_Tp>(__a, __n, __default_initialize_tag{});
+    using _ForOverwriteAllocator = __allocator_traits_rebind_t<_Alloc, __for_overwrite_tag>;
+    _ForOverwriteAllocator __alloc(__a);
+    return std::__allocate_shared_unbounded_array<_Tp>(__alloc, __n);
 }
 
 template<class _Tp, class = __enable_if_t<is_unbounded_array<_Tp>::value>>
@@ -1239,7 +1305,7 @@ template<class _Tp, __enable_if_t<is_unbounded_array<_Tp>::value, int> = 0>
 _LIBCPP_HIDE_FROM_ABI
 shared_ptr<_Tp> make_shared_for_overwrite(size_t __n)
 {
-    return std::__allocate_shared_unbounded_array<_Tp>(allocator<_Tp>(), __n, __default_initialize_tag{});
+    return std::__allocate_shared_unbounded_array<_Tp>(allocator<__for_overwrite_tag>(), __n);
 }
 
 #endif // _LIBCPP_STD_VER > 17
@@ -1465,7 +1531,7 @@ reinterpret_pointer_cast(const shared_ptr<_Up>& __r) _NOEXCEPT
                                typename shared_ptr<_Tp>::element_type*>(__r.get()));
 }
 
-#ifndef _LIBCPP_NO_RTTI
+#ifndef _LIBCPP_HAS_NO_RTTI
 
 template<class _Dp, class _Tp>
 inline _LIBCPP_INLINE_VISIBILITY
@@ -1475,7 +1541,7 @@ get_deleter(const shared_ptr<_Tp>& __p) _NOEXCEPT
     return __p.template __get_deleter<_Dp>();
 }
 
-#endif // _LIBCPP_NO_RTTI
+#endif // _LIBCPP_HAS_NO_RTTI
 
 template<class _Tp>
 class _LIBCPP_SHARED_PTR_TRIVIAL_ABI _LIBCPP_TEMPLATE_VIS weak_ptr
lib/libcxx/include/__memory/uninitialized_algorithms.h
@@ -410,7 +410,7 @@ constexpr void __allocator_destroy_multidimensional(_Alloc& __alloc, _BidirIter
 // This function assumes that the allocator is bound to the correct type.
 template<class _Alloc, class _Tp>
 _LIBCPP_HIDE_FROM_ABI
-constexpr void __allocator_construct_at(_Alloc& __alloc, _Tp* __loc) {
+constexpr void __allocator_construct_at_multidimensional(_Alloc& __alloc, _Tp* __loc) {
     static_assert(is_same_v<typename allocator_traits<_Alloc>::value_type, _Tp>,
         "The allocator should already be rebound to the correct type");
 
@@ -426,7 +426,7 @@ constexpr void __allocator_construct_at(_Alloc& __alloc, _Tp* __loc) {
         });
 
         for (; __i != extent_v<_Tp>; ++__i) {
-            std::__allocator_construct_at(__elem_alloc, std::addressof(__array[__i]));
+            std::__allocator_construct_at_multidimensional(__elem_alloc, std::addressof(__array[__i]));
         }
         __guard.__complete();
     } else {
@@ -446,13 +446,13 @@ constexpr void __allocator_construct_at(_Alloc& __alloc, _Tp* __loc) {
 // This function assumes that the allocator is bound to the correct type.
 template<class _Alloc, class _Tp, class _Arg>
 _LIBCPP_HIDE_FROM_ABI
-constexpr void __allocator_construct_at(_Alloc& __alloc, _Tp* __loc, _Arg const& __arg) {
+constexpr void __allocator_construct_at_multidimensional(_Alloc& __alloc, _Tp* __loc, _Arg const& __arg) {
     static_assert(is_same_v<typename allocator_traits<_Alloc>::value_type, _Tp>,
         "The allocator should already be rebound to the correct type");
 
     if constexpr (is_array_v<_Tp>) {
         static_assert(is_array_v<_Arg>,
-            "Provided non-array initialization argument to __allocator_construct_at when "
+            "Provided non-array initialization argument to __allocator_construct_at_multidimensional when "
             "trying to construct an array.");
 
         using _Element = remove_extent_t<_Tp>;
@@ -465,7 +465,7 @@ constexpr void __allocator_construct_at(_Alloc& __alloc, _Tp* __loc, _Arg const&
           std::__allocator_destroy_multidimensional(__elem_alloc, __array, __array + __i);
         });
         for (; __i != extent_v<_Tp>; ++__i) {
-            std::__allocator_construct_at(__elem_alloc, std::addressof(__array[__i]), __arg[__i]);
+            std::__allocator_construct_at_multidimensional(__elem_alloc, std::addressof(__array[__i]), __arg[__i]);
         }
         __guard.__complete();
     } else {
@@ -481,8 +481,8 @@ constexpr void __allocator_construct_at(_Alloc& __alloc, _Tp* __loc, _Arg const&
 // initialization using allocator_traits destruction. If the elements in the range are C-style
 // arrays, they are initialized element-wise using allocator construction, and recursively so.
 template<class _Alloc, class _BidirIter, class _Tp, class _Size = typename iterator_traits<_BidirIter>::difference_type>
-_LIBCPP_HIDE_FROM_ABI
-constexpr void __uninitialized_allocator_fill_n(_Alloc& __alloc, _BidirIter __it, _Size __n, _Tp const& __value) {
+_LIBCPP_HIDE_FROM_ABI constexpr void
+__uninitialized_allocator_fill_n_multidimensional(_Alloc& __alloc, _BidirIter __it, _Size __n, _Tp const& __value) {
     using _ValueType = typename iterator_traits<_BidirIter>::value_type;
     __allocator_traits_rebind_t<_Alloc, _ValueType> __value_alloc(__alloc);
     _BidirIter __begin = __it;
@@ -490,16 +490,16 @@ constexpr void __uninitialized_allocator_fill_n(_Alloc& __alloc, _BidirIter __it
     // If an exception is thrown, destroy what we have constructed so far in reverse order.
     __exception_guard __guard([&]() { std::__allocator_destroy_multidimensional(__value_alloc, __begin, __it); });
     for (; __n != 0; --__n, ++__it) {
-        std::__allocator_construct_at(__value_alloc, std::addressof(*__it), __value);
+        std::__allocator_construct_at_multidimensional(__value_alloc, std::addressof(*__it), __value);
     }
     __guard.__complete();
 }
 
-// Same as __uninitialized_allocator_fill_n, but doesn't pass any initialization argument
+// Same as __uninitialized_allocator_fill_n_multidimensional, but doesn't pass any initialization argument
 // to the allocator's construct method, which results in value initialization.
-template<class _Alloc, class _BidirIter, class _Size = typename iterator_traits<_BidirIter>::difference_type>
-_LIBCPP_HIDE_FROM_ABI
-constexpr void __uninitialized_allocator_value_construct_n(_Alloc& __alloc, _BidirIter __it, _Size __n) {
+template <class _Alloc, class _BidirIter, class _Size = typename iterator_traits<_BidirIter>::difference_type>
+_LIBCPP_HIDE_FROM_ABI constexpr void
+__uninitialized_allocator_value_construct_n_multidimensional(_Alloc& __alloc, _BidirIter __it, _Size __n) {
     using _ValueType = typename iterator_traits<_BidirIter>::value_type;
     __allocator_traits_rebind_t<_Alloc, _ValueType> __value_alloc(__alloc);
     _BidirIter __begin = __it;
@@ -507,7 +507,7 @@ constexpr void __uninitialized_allocator_value_construct_n(_Alloc& __alloc, _Bid
     // If an exception is thrown, destroy what we have constructed so far in reverse order.
     __exception_guard __guard([&]() { std::__allocator_destroy_multidimensional(__value_alloc, __begin, __it); });
     for (; __n != 0; --__n, ++__it) {
-        std::__allocator_construct_at(__value_alloc, std::addressof(*__it));
+        std::__allocator_construct_at_multidimensional(__value_alloc, std::addressof(*__it));
     }
     __guard.__complete();
 }
lib/libcxx/include/__ranges/elements_view.h
@@ -49,12 +49,6 @@ _LIBCPP_BEGIN_NAMESPACE_STD
 
 namespace ranges {
 
-template <class _View, size_t _Np, bool _Const>
-class __elements_view_iterator;
-
-template <class _View, size_t _Np, bool _Const>
-class __elements_view_sentinel;
-
 template <class _Tp, size_t _Np>
 concept __has_tuple_element = __tuple_like<_Tp> && _Np < tuple_size<_Tp>::value;
 
@@ -66,6 +60,13 @@ template <input_range _View, size_t _Np>
            __has_tuple_element<remove_reference_t<range_reference_t<_View>>, _Np> &&
            __returnable_element<range_reference_t<_View>, _Np>
 class elements_view : public view_interface<elements_view<_View, _Np>> {
+private:
+  template <bool>
+  class __iterator;
+
+  template <bool>
+  class __sentinel;
+
 public:
   _LIBCPP_HIDE_FROM_ABI elements_view()
     requires default_initializable<_View>
@@ -130,12 +131,6 @@ public:
   }
 
 private:
-  template <bool _Const>
-  using __iterator = __elements_view_iterator<_View, _Np, _Const>;
-
-  template <bool _Const>
-  using __sentinel = __elements_view_sentinel<_View, _Np, _Const>;
-
   _LIBCPP_NO_UNIQUE_ADDRESS _View __base_ = _View();
 };
 
@@ -160,13 +155,18 @@ struct __elements_view_iterator_category_base<_Base, _Np> {
   using iterator_category = decltype(__get_iterator_category());
 };
 
-template <class _View, size_t _Np, bool _Const>
-class __elements_view_iterator : public __elements_view_iterator_category_base<__maybe_const<_Const, _View>, _Np> {
-  template <class, size_t, bool >
-  friend class __elements_view_iterator;
+template <input_range _View, size_t _Np>
+  requires view<_View> && __has_tuple_element<range_value_t<_View>, _Np> &&
+           __has_tuple_element<remove_reference_t<range_reference_t<_View>>, _Np> &&
+           __returnable_element<range_reference_t<_View>, _Np>
+template <bool _Const>
+class elements_view<_View, _Np>::__iterator
+    : public __elements_view_iterator_category_base<__maybe_const<_Const, _View>, _Np> {
+  template <bool>
+  friend class __iterator;
 
-  template <class, size_t, bool >
-  friend class __elements_view_sentinel;
+  template <bool>
+  friend class __sentinel;
 
   using _Base = __maybe_const<_Const, _View>;
 
@@ -198,14 +198,13 @@ public:
   using value_type       = remove_cvref_t<tuple_element_t<_Np, range_value_t<_Base>>>;
   using difference_type  = range_difference_t<_Base>;
 
-  _LIBCPP_HIDE_FROM_ABI __elements_view_iterator()
+  _LIBCPP_HIDE_FROM_ABI __iterator()
     requires default_initializable<iterator_t<_Base>>
   = default;
 
-  _LIBCPP_HIDE_FROM_ABI constexpr explicit __elements_view_iterator(iterator_t<_Base> __current)
-      : __current_(std::move(__current)) {}
+  _LIBCPP_HIDE_FROM_ABI constexpr explicit __iterator(iterator_t<_Base> __current) : __current_(std::move(__current)) {}
 
-  _LIBCPP_HIDE_FROM_ABI constexpr __elements_view_iterator(__elements_view_iterator<_View, _Np, !_Const> __i)
+  _LIBCPP_HIDE_FROM_ABI constexpr __iterator(__iterator<!_Const> __i)
     requires _Const && convertible_to<iterator_t<_View>, iterator_t<_Base>>
       : __current_(std::move(__i.__current_)) {}
 
@@ -215,14 +214,14 @@ public:
 
   _LIBCPP_HIDE_FROM_ABI constexpr decltype(auto) operator*() const { return __get_element(__current_); }
 
-  _LIBCPP_HIDE_FROM_ABI constexpr __elements_view_iterator& operator++() {
+  _LIBCPP_HIDE_FROM_ABI constexpr __iterator& operator++() {
     ++__current_;
     return *this;
   }
 
   _LIBCPP_HIDE_FROM_ABI constexpr void operator++(int) { ++__current_; }
 
-  _LIBCPP_HIDE_FROM_ABI constexpr __elements_view_iterator operator++(int)
+  _LIBCPP_HIDE_FROM_ABI constexpr __iterator operator++(int)
     requires forward_range<_Base>
   {
     auto temp = *this;
@@ -230,14 +229,14 @@ public:
     return temp;
   }
 
-  _LIBCPP_HIDE_FROM_ABI constexpr __elements_view_iterator& operator--()
+  _LIBCPP_HIDE_FROM_ABI constexpr __iterator& operator--()
     requires bidirectional_range<_Base>
   {
     --__current_;
     return *this;
   }
 
-  _LIBCPP_HIDE_FROM_ABI constexpr __elements_view_iterator operator--(int)
+  _LIBCPP_HIDE_FROM_ABI constexpr __iterator operator--(int)
     requires bidirectional_range<_Base>
   {
     auto temp = *this;
@@ -245,14 +244,14 @@ public:
     return temp;
   }
 
-  _LIBCPP_HIDE_FROM_ABI constexpr __elements_view_iterator& operator+=(difference_type __n)
+  _LIBCPP_HIDE_FROM_ABI constexpr __iterator& operator+=(difference_type __n)
     requires random_access_range<_Base>
   {
     __current_ += __n;
     return *this;
   }
 
-  _LIBCPP_HIDE_FROM_ABI constexpr __elements_view_iterator& operator-=(difference_type __n)
+  _LIBCPP_HIDE_FROM_ABI constexpr __iterator& operator-=(difference_type __n)
     requires random_access_range<_Base>
   {
     __current_ -= __n;
@@ -265,99 +264,91 @@ public:
     return __get_element(__current_ + __n);
   }
 
-  _LIBCPP_HIDE_FROM_ABI friend constexpr bool
-  operator==(const __elements_view_iterator& __x, const __elements_view_iterator& __y)
+  _LIBCPP_HIDE_FROM_ABI friend constexpr bool operator==(const __iterator& __x, const __iterator& __y)
     requires equality_comparable<iterator_t<_Base>>
   {
     return __x.__current_ == __y.__current_;
   }
 
-  _LIBCPP_HIDE_FROM_ABI friend constexpr bool
-  operator<(const __elements_view_iterator& __x, const __elements_view_iterator& __y)
+  _LIBCPP_HIDE_FROM_ABI friend constexpr bool operator<(const __iterator& __x, const __iterator& __y)
     requires random_access_range<_Base>
   {
     return __x.__current_ < __y.__current_;
   }
 
-  _LIBCPP_HIDE_FROM_ABI friend constexpr bool
-  operator>(const __elements_view_iterator& __x, const __elements_view_iterator& __y)
+  _LIBCPP_HIDE_FROM_ABI friend constexpr bool operator>(const __iterator& __x, const __iterator& __y)
     requires random_access_range<_Base>
   {
     return __y < __x;
   }
 
-  _LIBCPP_HIDE_FROM_ABI friend constexpr bool
-  operator<=(const __elements_view_iterator& __x, const __elements_view_iterator& __y)
+  _LIBCPP_HIDE_FROM_ABI friend constexpr bool operator<=(const __iterator& __x, const __iterator& __y)
     requires random_access_range<_Base>
   {
     return !(__y < __x);
   }
 
-  _LIBCPP_HIDE_FROM_ABI friend constexpr bool
-  operator>=(const __elements_view_iterator& __x, const __elements_view_iterator& __y)
+  _LIBCPP_HIDE_FROM_ABI friend constexpr bool operator>=(const __iterator& __x, const __iterator& __y)
     requires random_access_range<_Base>
   {
     return !(__x < __y);
   }
 
-  _LIBCPP_HIDE_FROM_ABI friend constexpr auto
-  operator<=>(const __elements_view_iterator& __x, const __elements_view_iterator& __y)
+  _LIBCPP_HIDE_FROM_ABI friend constexpr auto operator<=>(const __iterator& __x, const __iterator& __y)
     requires random_access_range<_Base> && three_way_comparable<iterator_t<_Base>>
   {
     return __x.__current_ <=> __y.__current_;
   }
 
-  _LIBCPP_HIDE_FROM_ABI friend constexpr __elements_view_iterator
-  operator+(const __elements_view_iterator& __x, difference_type __y)
+  _LIBCPP_HIDE_FROM_ABI friend constexpr __iterator operator+(const __iterator& __x, difference_type __y)
     requires random_access_range<_Base>
   {
-    return __elements_view_iterator{__x} += __y;
+    return __iterator{__x} += __y;
   }
 
-  _LIBCPP_HIDE_FROM_ABI friend constexpr __elements_view_iterator
-  operator+(difference_type __x, const __elements_view_iterator& __y)
+  _LIBCPP_HIDE_FROM_ABI friend constexpr __iterator operator+(difference_type __x, const __iterator& __y)
     requires random_access_range<_Base>
   {
     return __y + __x;
   }
 
-  _LIBCPP_HIDE_FROM_ABI friend constexpr __elements_view_iterator
-  operator-(const __elements_view_iterator& __x, difference_type __y)
+  _LIBCPP_HIDE_FROM_ABI friend constexpr __iterator operator-(const __iterator& __x, difference_type __y)
     requires random_access_range<_Base>
   {
-    return __elements_view_iterator{__x} -= __y;
+    return __iterator{__x} -= __y;
   }
 
-  _LIBCPP_HIDE_FROM_ABI friend constexpr difference_type
-  operator-(const __elements_view_iterator& __x, const __elements_view_iterator& __y)
+  _LIBCPP_HIDE_FROM_ABI friend constexpr difference_type operator-(const __iterator& __x, const __iterator& __y)
     requires sized_sentinel_for<iterator_t<_Base>, iterator_t<_Base>>
   {
     return __x.__current_ - __y.__current_;
   }
 };
 
-template <class _View, size_t _Np, bool _Const>
-class __elements_view_sentinel {
+template <input_range _View, size_t _Np>
+  requires view<_View> && __has_tuple_element<range_value_t<_View>, _Np> &&
+           __has_tuple_element<remove_reference_t<range_reference_t<_View>>, _Np> &&
+           __returnable_element<range_reference_t<_View>, _Np>
+template <bool _Const>
+class elements_view<_View, _Np>::__sentinel {
 private:
   using _Base                                        = __maybe_const<_Const, _View>;
   _LIBCPP_NO_UNIQUE_ADDRESS sentinel_t<_Base> __end_ = sentinel_t<_Base>();
 
-  template <class, size_t, bool >
-  friend class __elements_view_sentinel;
+  template <bool>
+  friend class __sentinel;
 
   template <bool _AnyConst>
-  _LIBCPP_HIDE_FROM_ABI static constexpr decltype(auto)
-  __get_current(const __elements_view_iterator<_View, _Np, _AnyConst>& __iter) {
+  _LIBCPP_HIDE_FROM_ABI static constexpr decltype(auto) __get_current(const __iterator<_AnyConst>& __iter) {
     return (__iter.__current_);
   }
 
 public:
-  _LIBCPP_HIDE_FROM_ABI __elements_view_sentinel() = default;
+  _LIBCPP_HIDE_FROM_ABI __sentinel() = default;
 
-  _LIBCPP_HIDE_FROM_ABI constexpr explicit __elements_view_sentinel(sentinel_t<_Base> __end)
-      : __end_(std::move(__end)) {}
+  _LIBCPP_HIDE_FROM_ABI constexpr explicit __sentinel(sentinel_t<_Base> __end) : __end_(std::move(__end)) {}
 
-  _LIBCPP_HIDE_FROM_ABI constexpr __elements_view_sentinel(__elements_view_sentinel<_View, _Np, !_Const> __other)
+  _LIBCPP_HIDE_FROM_ABI constexpr __sentinel(__sentinel<!_Const> __other)
     requires _Const && convertible_to<sentinel_t<_View>, sentinel_t<_Base>>
       : __end_(std::move(__other.__end_)) {}
 
@@ -365,22 +356,21 @@ public:
 
   template <bool _OtherConst>
     requires sentinel_for<sentinel_t<_Base>, iterator_t<__maybe_const<_OtherConst, _View>>>
-  _LIBCPP_HIDE_FROM_ABI friend constexpr bool
-  operator==(const __elements_view_iterator<_View, _Np, _OtherConst>& __x, const __elements_view_sentinel& __y) {
+  _LIBCPP_HIDE_FROM_ABI friend constexpr bool operator==(const __iterator<_OtherConst>& __x, const __sentinel& __y) {
     return __get_current(__x) == __y.__end_;
   }
 
   template <bool _OtherConst>
     requires sized_sentinel_for<sentinel_t<_Base>, iterator_t<__maybe_const<_OtherConst, _View>>>
   _LIBCPP_HIDE_FROM_ABI friend constexpr range_difference_t<__maybe_const<_OtherConst, _View>>
-  operator-(const __elements_view_iterator<_View, _Np, _OtherConst>& __x, const __elements_view_sentinel& __y) {
+  operator-(const __iterator<_OtherConst>& __x, const __sentinel& __y) {
     return __get_current(__x) - __y.__end_;
   }
 
   template <bool _OtherConst>
     requires sized_sentinel_for<sentinel_t<_Base>, iterator_t<__maybe_const<_OtherConst, _View>>>
   _LIBCPP_HIDE_FROM_ABI friend constexpr range_difference_t<__maybe_const<_OtherConst, _View>>
-  operator-(const __elements_view_sentinel& __x, const __elements_view_iterator<_View, _Np, _OtherConst>& __y) {
+  operator-(const __sentinel& __x, const __iterator<_OtherConst>& __y) {
     return __x.__end_ - __get_current(__y);
   }
 };
lib/libcxx/include/__ranges/filter_view.h
@@ -46,15 +46,6 @@ _LIBCPP_BEGIN_NAMESPACE_STD
 #if _LIBCPP_STD_VER > 17
 
 namespace ranges {
-
-  template <input_range _View, indirect_unary_predicate<iterator_t<_View>> _Pred>
-    requires view<_View> && is_object_v<_Pred>
-  class __filter_view_iterator;
-
-  template <input_range _View, indirect_unary_predicate<iterator_t<_View>> _Pred>
-    requires view<_View> && is_object_v<_Pred>
-  class __filter_view_sentinel;
-
   template<input_range _View, indirect_unary_predicate<iterator_t<_View>> _Pred>
     requires view<_View> && is_object_v<_Pred>
   class filter_view : public view_interface<filter_view<_View, _Pred>> {
@@ -67,11 +58,8 @@ namespace ranges {
     using _Cache = _If<_UseCache, __non_propagating_cache<iterator_t<_View>>, __empty_cache>;
     _LIBCPP_NO_UNIQUE_ADDRESS _Cache __cached_begin_ = _Cache();
 
-    using __iterator = __filter_view_iterator<_View, _Pred>;
-    using __sentinel = __filter_view_sentinel<_View, _Pred>;
-
-    friend __iterator;
-    friend __sentinel;
+    class __iterator;
+    class __sentinel;
 
   public:
     _LIBCPP_HIDE_FROM_ABI
@@ -131,13 +119,11 @@ namespace ranges {
 
   template<input_range _View, indirect_unary_predicate<iterator_t<_View>> _Pred>
     requires view<_View> && is_object_v<_Pred>
-  class __filter_view_iterator : public __filter_iterator_category<_View> {
-
-    using __filter_view = filter_view<_View, _Pred>;
+  class filter_view<_View, _Pred>::__iterator : public __filter_iterator_category<_View> {
 
   public:
     _LIBCPP_NO_UNIQUE_ADDRESS iterator_t<_View> __current_ = iterator_t<_View>();
-    _LIBCPP_NO_UNIQUE_ADDRESS __filter_view* __parent_ = nullptr;
+    _LIBCPP_NO_UNIQUE_ADDRESS filter_view* __parent_ = nullptr;
 
     using iterator_concept =
       _If<bidirectional_range<_View>, bidirectional_iterator_tag,
@@ -149,10 +135,10 @@ namespace ranges {
     using difference_type = range_difference_t<_View>;
 
     _LIBCPP_HIDE_FROM_ABI
-    __filter_view_iterator() requires default_initializable<iterator_t<_View>> = default;
+    __iterator() requires default_initializable<iterator_t<_View>> = default;
 
     _LIBCPP_HIDE_FROM_ABI
-    constexpr __filter_view_iterator(__filter_view& __parent, iterator_t<_View> __current)
+    constexpr __iterator(filter_view& __parent, iterator_t<_View> __current)
       : __current_(std::move(__current)), __parent_(std::addressof(__parent))
     { }
 
@@ -171,7 +157,7 @@ namespace ranges {
     }
 
     _LIBCPP_HIDE_FROM_ABI
-    constexpr __filter_view_iterator& operator++() {
+    constexpr __iterator& operator++() {
       __current_ = ranges::find_if(std::move(++__current_), ranges::end(__parent_->__base_),
                                    std::ref(*__parent_->__pred_));
       return *this;
@@ -179,42 +165,42 @@ namespace ranges {
     _LIBCPP_HIDE_FROM_ABI
     constexpr void operator++(int) { ++*this; }
     _LIBCPP_HIDE_FROM_ABI
-    constexpr __filter_view_iterator operator++(int) requires forward_range<_View> {
+    constexpr __iterator operator++(int) requires forward_range<_View> {
       auto __tmp = *this;
       ++*this;
       return __tmp;
     }
 
     _LIBCPP_HIDE_FROM_ABI
-    constexpr __filter_view_iterator& operator--() requires bidirectional_range<_View> {
+    constexpr __iterator& operator--() requires bidirectional_range<_View> {
       do {
         --__current_;
       } while (!std::invoke(*__parent_->__pred_, *__current_));
       return *this;
     }
     _LIBCPP_HIDE_FROM_ABI
-    constexpr __filter_view_iterator operator--(int) requires bidirectional_range<_View> {
+    constexpr __iterator operator--(int) requires bidirectional_range<_View> {
       auto tmp = *this;
       --*this;
       return tmp;
     }
 
     _LIBCPP_HIDE_FROM_ABI
-    friend constexpr bool operator==(__filter_view_iterator const& __x, __filter_view_iterator const& __y)
+    friend constexpr bool operator==(__iterator const& __x, __iterator const& __y)
       requires equality_comparable<iterator_t<_View>>
     {
       return __x.__current_ == __y.__current_;
     }
 
     _LIBCPP_HIDE_FROM_ABI
-    friend constexpr range_rvalue_reference_t<_View> iter_move(__filter_view_iterator const& __it)
+    friend constexpr range_rvalue_reference_t<_View> iter_move(__iterator const& __it)
       noexcept(noexcept(ranges::iter_move(__it.__current_)))
     {
       return ranges::iter_move(__it.__current_);
     }
 
     _LIBCPP_HIDE_FROM_ABI
-    friend constexpr void iter_swap(__filter_view_iterator const& __x, __filter_view_iterator const& __y)
+    friend constexpr void iter_swap(__iterator const& __x, __iterator const& __y)
       noexcept(noexcept(ranges::iter_swap(__x.__current_, __y.__current_)))
       requires indirectly_swappable<iterator_t<_View>>
     {
@@ -224,17 +210,15 @@ namespace ranges {
 
   template<input_range _View, indirect_unary_predicate<iterator_t<_View>> _Pred>
     requires view<_View> && is_object_v<_Pred>
-  class __filter_view_sentinel {
-    using __filter_view = filter_view<_View, _Pred>;
-
+  class filter_view<_View, _Pred>::__sentinel {
   public:
     sentinel_t<_View> __end_ = sentinel_t<_View>();
 
     _LIBCPP_HIDE_FROM_ABI
-    __filter_view_sentinel() = default;
+    __sentinel() = default;
 
     _LIBCPP_HIDE_FROM_ABI
-    constexpr explicit __filter_view_sentinel(__filter_view& __parent)
+    constexpr explicit __sentinel(filter_view& __parent)
       : __end_(ranges::end(__parent.__base_))
     { }
 
@@ -242,7 +226,7 @@ namespace ranges {
     constexpr sentinel_t<_View> base() const { return __end_; }
 
     _LIBCPP_HIDE_FROM_ABI friend constexpr bool
-    operator==(__filter_view_iterator<_View, _Pred> const& __x, __filter_view_sentinel const& __y) {
+    operator==(__iterator const& __x, __sentinel const& __y) {
       return __x.__current_ == __y.__end_;
     }
   };
lib/libcxx/include/__ranges/iota_view.h
@@ -83,14 +83,6 @@ namespace ranges {
       { __j - __j } -> convertible_to<_IotaDiffT<_Iter>>;
     };
 
-  template <weakly_incrementable _Start>
-    requires copyable<_Start>
-  struct __iota_view_iterator;
-
-  template <weakly_incrementable _Start, semiregular _BoundSentinel>
-    requires __weakly_equality_comparable_with<_Start, _BoundSentinel> && copyable<_Start>
-  struct __iota_view_sentinel;
-
   template<class>
   struct __iota_iterator_category {};
 
@@ -102,9 +94,211 @@ namespace ranges {
   template <weakly_incrementable _Start, semiregular _BoundSentinel = unreachable_sentinel_t>
     requires __weakly_equality_comparable_with<_Start, _BoundSentinel> && copyable<_Start>
   class iota_view : public view_interface<iota_view<_Start, _BoundSentinel>> {
+    struct __iterator : public __iota_iterator_category<_Start> {
+      friend class iota_view;
+
+      using iterator_concept =
+        _If<__advanceable<_Start>,   random_access_iterator_tag,
+        _If<__decrementable<_Start>, bidirectional_iterator_tag,
+        _If<incrementable<_Start>,   forward_iterator_tag,
+        /*Else*/                     input_iterator_tag>>>;
+
+      using value_type = _Start;
+      using difference_type = _IotaDiffT<_Start>;
+
+      _Start __value_ = _Start();
+
+      _LIBCPP_HIDE_FROM_ABI
+      __iterator() requires default_initializable<_Start> = default;
+
+      _LIBCPP_HIDE_FROM_ABI
+      constexpr explicit __iterator(_Start __value) : __value_(std::move(__value)) {}
+
+      _LIBCPP_HIDE_FROM_ABI
+      constexpr _Start operator*() const noexcept(is_nothrow_copy_constructible_v<_Start>) {
+        return __value_;
+      }
+
+      _LIBCPP_HIDE_FROM_ABI
+      constexpr __iterator& operator++() {
+        ++__value_;
+        return *this;
+      }
+
+      _LIBCPP_HIDE_FROM_ABI
+      constexpr void operator++(int) { ++*this; }
+
+      _LIBCPP_HIDE_FROM_ABI
+      constexpr __iterator operator++(int) requires incrementable<_Start> {
+        auto __tmp = *this;
+        ++*this;
+        return __tmp;
+      }
+
+      _LIBCPP_HIDE_FROM_ABI
+      constexpr __iterator& operator--() requires __decrementable<_Start> {
+        --__value_;
+        return *this;
+      }
+
+      _LIBCPP_HIDE_FROM_ABI
+      constexpr __iterator  operator--(int) requires __decrementable<_Start> {
+        auto __tmp = *this;
+        --*this;
+        return __tmp;
+      }
+
+      _LIBCPP_HIDE_FROM_ABI
+      constexpr __iterator& operator+=(difference_type __n)
+        requires __advanceable<_Start>
+      {
+        if constexpr (__integer_like<_Start> && !__signed_integer_like<_Start>) {
+          if (__n >= difference_type(0)) {
+            __value_ += static_cast<_Start>(__n);
+          } else {
+            __value_ -= static_cast<_Start>(-__n);
+          }
+        } else {
+          __value_ += __n;
+        }
+        return *this;
+      }
+
+      _LIBCPP_HIDE_FROM_ABI
+      constexpr __iterator& operator-=(difference_type __n)
+        requires __advanceable<_Start>
+      {
+        if constexpr (__integer_like<_Start> && !__signed_integer_like<_Start>) {
+          if (__n >= difference_type(0)) {
+            __value_ -= static_cast<_Start>(__n);
+          } else {
+            __value_ += static_cast<_Start>(-__n);
+          }
+        } else {
+          __value_ -= __n;
+        }
+        return *this;
+      }
+
+      _LIBCPP_HIDE_FROM_ABI
+      constexpr _Start operator[](difference_type __n) const
+        requires __advanceable<_Start>
+      {
+        return _Start(__value_ + __n);
+      }
+
+      _LIBCPP_HIDE_FROM_ABI
+      friend constexpr bool operator==(const __iterator& __x, const __iterator& __y)
+        requires equality_comparable<_Start>
+      {
+        return __x.__value_ == __y.__value_;
+      }
 
-    using __iterator = __iota_view_iterator<_Start>;
-    using __sentinel = __iota_view_sentinel<_Start, _BoundSentinel>;
+      _LIBCPP_HIDE_FROM_ABI
+      friend constexpr bool operator<(const __iterator& __x, const __iterator& __y)
+        requires totally_ordered<_Start>
+      {
+        return __x.__value_ < __y.__value_;
+      }
+
+      _LIBCPP_HIDE_FROM_ABI
+      friend constexpr bool operator>(const __iterator& __x, const __iterator& __y)
+        requires totally_ordered<_Start>
+      {
+        return __y < __x;
+      }
+
+      _LIBCPP_HIDE_FROM_ABI
+      friend constexpr bool operator<=(const __iterator& __x, const __iterator& __y)
+        requires totally_ordered<_Start>
+      {
+        return !(__y < __x);
+      }
+
+      _LIBCPP_HIDE_FROM_ABI
+      friend constexpr bool operator>=(const __iterator& __x, const __iterator& __y)
+        requires totally_ordered<_Start>
+      {
+        return !(__x < __y);
+      }
+
+      _LIBCPP_HIDE_FROM_ABI
+      friend constexpr auto operator<=>(const __iterator& __x, const __iterator& __y)
+        requires totally_ordered<_Start> && three_way_comparable<_Start>
+      {
+        return __x.__value_ <=> __y.__value_;
+      }
+
+      _LIBCPP_HIDE_FROM_ABI
+      friend constexpr __iterator operator+(__iterator __i, difference_type __n)
+        requires __advanceable<_Start>
+      {
+        __i += __n;
+        return __i;
+      }
+
+      _LIBCPP_HIDE_FROM_ABI
+      friend constexpr __iterator operator+(difference_type __n, __iterator __i)
+        requires __advanceable<_Start>
+      {
+        return __i + __n;
+      }
+
+      _LIBCPP_HIDE_FROM_ABI
+      friend constexpr __iterator operator-(__iterator __i, difference_type __n)
+        requires __advanceable<_Start>
+      {
+        __i -= __n;
+        return __i;
+      }
+
+      _LIBCPP_HIDE_FROM_ABI
+      friend constexpr difference_type operator-(const __iterator& __x, const __iterator& __y)
+        requires __advanceable<_Start>
+      {
+        if constexpr (__integer_like<_Start>) {
+          if constexpr (__signed_integer_like<_Start>) {
+            return difference_type(difference_type(__x.__value_) - difference_type(__y.__value_));
+          }
+          if (__y.__value_ > __x.__value_) {
+            return difference_type(-difference_type(__y.__value_ - __x.__value_));
+          }
+          return difference_type(__x.__value_ - __y.__value_);
+        }
+        return __x.__value_ - __y.__value_;
+      }
+    };
+
+    struct __sentinel {
+      friend class iota_view;
+
+    private:
+      _BoundSentinel __bound_sentinel_ = _BoundSentinel();
+
+    public:
+      _LIBCPP_HIDE_FROM_ABI
+      __sentinel() = default;
+      constexpr explicit __sentinel(_BoundSentinel __bound_sentinel) : __bound_sentinel_(std::move(__bound_sentinel)) {}
+
+      _LIBCPP_HIDE_FROM_ABI
+      friend constexpr bool operator==(const __iterator& __x, const __sentinel& __y) {
+        return __x.__value_ == __y.__bound_sentinel_;
+      }
+
+      _LIBCPP_HIDE_FROM_ABI
+      friend constexpr iter_difference_t<_Start> operator-(const __iterator& __x, const __sentinel& __y)
+        requires sized_sentinel_for<_BoundSentinel, _Start>
+      {
+        return __x.__value_ - __y.__bound_sentinel_;
+      }
+
+      _LIBCPP_HIDE_FROM_ABI
+      friend constexpr iter_difference_t<_Start> operator-(const __sentinel& __x, const __iterator& __y)
+        requires sized_sentinel_for<_BoundSentinel, _Start>
+      {
+        return -(__y - __x);
+      }
+    };
 
     _Start __value_ = _Start();
     _BoundSentinel __bound_sentinel_ = _BoundSentinel();
@@ -185,224 +379,6 @@ namespace ranges {
   template <class _Start, class _BoundSentinel>
   inline constexpr bool enable_borrowed_range<iota_view<_Start, _BoundSentinel>> = true;
 
-  template <weakly_incrementable _Start>
-    requires copyable<_Start>
-  struct __iota_view_iterator : public __iota_iterator_category<_Start> {
-
-    template <weakly_incrementable _StartT, semiregular _BoundSentinelT>
-      requires __weakly_equality_comparable_with<_StartT, _BoundSentinelT> && copyable<_StartT>
-    friend class iota_view;
-
-    using iterator_concept =
-      _If<__advanceable<_Start>,   random_access_iterator_tag,
-      _If<__decrementable<_Start>, bidirectional_iterator_tag,
-      _If<incrementable<_Start>,   forward_iterator_tag,
-      /*Else*/                     input_iterator_tag>>>;
-
-    using value_type = _Start;
-    using difference_type = _IotaDiffT<_Start>;
-
-    _Start __value_ = _Start();
-
-    _LIBCPP_HIDE_FROM_ABI
-    __iota_view_iterator() requires default_initializable<_Start> = default;
-
-    _LIBCPP_HIDE_FROM_ABI
-    constexpr explicit __iota_view_iterator(_Start __value) : __value_(std::move(__value)) {}
-
-    _LIBCPP_HIDE_FROM_ABI
-    constexpr _Start operator*() const noexcept(is_nothrow_copy_constructible_v<_Start>) {
-      return __value_;
-    }
-
-    _LIBCPP_HIDE_FROM_ABI
-    constexpr __iota_view_iterator& operator++() {
-      ++__value_;
-      return *this;
-    }
-
-    _LIBCPP_HIDE_FROM_ABI
-    constexpr void operator++(int) { ++*this; }
-
-    _LIBCPP_HIDE_FROM_ABI
-    constexpr __iota_view_iterator operator++(int) requires incrementable<_Start> {
-      auto __tmp = *this;
-      ++*this;
-      return __tmp;
-    }
-
-    _LIBCPP_HIDE_FROM_ABI
-    constexpr __iota_view_iterator& operator--() requires __decrementable<_Start> {
-      --__value_;
-      return *this;
-    }
-
-    _LIBCPP_HIDE_FROM_ABI
-    constexpr __iota_view_iterator  operator--(int) requires __decrementable<_Start> {
-      auto __tmp = *this;
-      --*this;
-      return __tmp;
-    }
-
-    _LIBCPP_HIDE_FROM_ABI
-    constexpr __iota_view_iterator& operator+=(difference_type __n)
-      requires __advanceable<_Start>
-    {
-      if constexpr (__integer_like<_Start> && !__signed_integer_like<_Start>) {
-        if (__n >= difference_type(0)) {
-          __value_ += static_cast<_Start>(__n);
-        } else {
-          __value_ -= static_cast<_Start>(-__n);
-        }
-      } else {
-        __value_ += __n;
-      }
-      return *this;
-    }
-
-    _LIBCPP_HIDE_FROM_ABI
-    constexpr __iota_view_iterator& operator-=(difference_type __n)
-      requires __advanceable<_Start>
-    {
-      if constexpr (__integer_like<_Start> && !__signed_integer_like<_Start>) {
-        if (__n >= difference_type(0)) {
-          __value_ -= static_cast<_Start>(__n);
-        } else {
-          __value_ += static_cast<_Start>(-__n);
-        }
-      } else {
-        __value_ -= __n;
-      }
-      return *this;
-    }
-
-    _LIBCPP_HIDE_FROM_ABI
-    constexpr _Start operator[](difference_type __n) const
-      requires __advanceable<_Start>
-    {
-      return _Start(__value_ + __n);
-    }
-
-    _LIBCPP_HIDE_FROM_ABI
-    friend constexpr bool operator==(const __iota_view_iterator& __x, const __iota_view_iterator& __y)
-      requires equality_comparable<_Start>
-    {
-      return __x.__value_ == __y.__value_;
-    }
-
-    _LIBCPP_HIDE_FROM_ABI
-    friend constexpr bool operator<(const __iota_view_iterator& __x, const __iota_view_iterator& __y)
-      requires totally_ordered<_Start>
-    {
-      return __x.__value_ < __y.__value_;
-    }
-
-    _LIBCPP_HIDE_FROM_ABI
-    friend constexpr bool operator>(const __iota_view_iterator& __x, const __iota_view_iterator& __y)
-      requires totally_ordered<_Start>
-    {
-      return __y < __x;
-    }
-
-    _LIBCPP_HIDE_FROM_ABI
-    friend constexpr bool operator<=(const __iota_view_iterator& __x, const __iota_view_iterator& __y)
-      requires totally_ordered<_Start>
-    {
-      return !(__y < __x);
-    }
-
-    _LIBCPP_HIDE_FROM_ABI
-    friend constexpr bool operator>=(const __iota_view_iterator& __x, const __iota_view_iterator& __y)
-      requires totally_ordered<_Start>
-    {
-      return !(__x < __y);
-    }
-
-    _LIBCPP_HIDE_FROM_ABI
-    friend constexpr auto operator<=>(const __iota_view_iterator& __x, const __iota_view_iterator& __y)
-      requires totally_ordered<_Start> && three_way_comparable<_Start>
-    {
-      return __x.__value_ <=> __y.__value_;
-    }
-
-    _LIBCPP_HIDE_FROM_ABI
-    friend constexpr __iota_view_iterator operator+(__iota_view_iterator __i, difference_type __n)
-      requires __advanceable<_Start>
-    {
-      __i += __n;
-      return __i;
-    }
-
-    _LIBCPP_HIDE_FROM_ABI
-    friend constexpr __iota_view_iterator operator+(difference_type __n, __iota_view_iterator __i)
-      requires __advanceable<_Start>
-    {
-      return __i + __n;
-    }
-
-    _LIBCPP_HIDE_FROM_ABI
-    friend constexpr __iota_view_iterator operator-(__iota_view_iterator __i, difference_type __n)
-      requires __advanceable<_Start>
-    {
-      __i -= __n;
-      return __i;
-    }
-
-    _LIBCPP_HIDE_FROM_ABI
-    friend constexpr difference_type operator-(const __iota_view_iterator& __x, const __iota_view_iterator& __y)
-      requires __advanceable<_Start>
-    {
-      if constexpr (__integer_like<_Start>) {
-        if constexpr (__signed_integer_like<_Start>) {
-          return difference_type(difference_type(__x.__value_) - difference_type(__y.__value_));
-        }
-        if (__y.__value_ > __x.__value_) {
-          return difference_type(-difference_type(__y.__value_ - __x.__value_));
-        }
-        return difference_type(__x.__value_ - __y.__value_);
-      }
-      return __x.__value_ - __y.__value_;
-    }
-  };
-
-  template <weakly_incrementable _Start, semiregular _BoundSentinel>
-    requires __weakly_equality_comparable_with<_Start, _BoundSentinel> && copyable<_Start>
-  struct __iota_view_sentinel {
-
-    template <weakly_incrementable _StartT, semiregular _BoundSentinelT>
-      requires __weakly_equality_comparable_with<_StartT, _BoundSentinelT> && copyable<_StartT>
-    friend class iota_view;
-
-    using __iterator = __iota_view_iterator<_Start>;
-
-  private:
-    _BoundSentinel __bound_sentinel_ = _BoundSentinel();
-
-  public:
-    _LIBCPP_HIDE_FROM_ABI
-    __iota_view_sentinel() = default;
-    constexpr explicit __iota_view_sentinel(_BoundSentinel __bound_sentinel) : __bound_sentinel_(std::move(__bound_sentinel)) {}
-
-    _LIBCPP_HIDE_FROM_ABI
-    friend constexpr bool operator==(const __iterator& __x, const __iota_view_sentinel& __y) {
-      return __x.__value_ == __y.__bound_sentinel_;
-    }
-
-    _LIBCPP_HIDE_FROM_ABI
-    friend constexpr iter_difference_t<_Start> operator-(const __iterator& __x, const __iota_view_sentinel& __y)
-      requires sized_sentinel_for<_BoundSentinel, _Start>
-    {
-      return __x.__value_ - __y.__bound_sentinel_;
-    }
-
-    _LIBCPP_HIDE_FROM_ABI
-    friend constexpr iter_difference_t<_Start> operator-(const __iota_view_sentinel& __x, const __iterator& __y)
-      requires sized_sentinel_for<_BoundSentinel, _Start>
-    {
-      return -(__y - __x);
-    }
-  };
-
  namespace views {
  namespace __iota {
   struct __fn {
lib/libcxx/include/__ranges/istream_view.h
@@ -36,18 +36,10 @@ namespace ranges {
 template <class _Val, class _CharT, class _Traits>
 concept __stream_extractable = requires(basic_istream<_CharT, _Traits>& __is, _Val& __t) { __is >> __t; };
 
-template <movable _Val, class _CharT, class _Traits>
-  requires default_initializable<_Val> && __stream_extractable<_Val, _CharT, _Traits>
-class __basic_istream_view_iterator;
-
 template <movable _Val, class _CharT, class _Traits = char_traits<_CharT>>
   requires default_initializable<_Val> && __stream_extractable<_Val, _CharT, _Traits>
 class basic_istream_view : public view_interface<basic_istream_view<_Val, _CharT, _Traits>> {
-  using __iterator = __basic_istream_view_iterator<_Val, _CharT, _Traits>;
-
-  template <movable _ValueType, class _CharType, class _TraitsType>
-    requires default_initializable<_ValueType> && __stream_extractable<_ValueType, _CharType, _TraitsType>
-  friend class __basic_istream_view_iterator;
+  class __iterator;
 
 public:
   _LIBCPP_HIDE_FROM_ABI constexpr explicit basic_istream_view(basic_istream<_CharT, _Traits>& __stream)
@@ -67,23 +59,23 @@ private:
 
 template <movable _Val, class _CharT, class _Traits>
   requires default_initializable<_Val> && __stream_extractable<_Val, _CharT, _Traits>
-class __basic_istream_view_iterator {
+class basic_istream_view<_Val, _CharT, _Traits>::__iterator {
 public:
   using iterator_concept = input_iterator_tag;
   using difference_type  = ptrdiff_t;
   using value_type       = _Val;
 
-  _LIBCPP_HIDE_FROM_ABI constexpr explicit __basic_istream_view_iterator(
+  _LIBCPP_HIDE_FROM_ABI constexpr explicit __iterator(
       basic_istream_view<_Val, _CharT, _Traits>& __parent) noexcept
       : __parent_(std::addressof(__parent)) {}
 
-  __basic_istream_view_iterator(const __basic_istream_view_iterator&)                  = delete;
-  _LIBCPP_HIDE_FROM_ABI __basic_istream_view_iterator(__basic_istream_view_iterator&&) = default;
+  __iterator(const __iterator&)                  = delete;
+  _LIBCPP_HIDE_FROM_ABI __iterator(__iterator&&) = default;
 
-  __basic_istream_view_iterator& operator=(const __basic_istream_view_iterator&)                  = delete;
-  _LIBCPP_HIDE_FROM_ABI __basic_istream_view_iterator& operator=(__basic_istream_view_iterator&&) = default;
+  __iterator& operator=(const __iterator&)                  = delete;
+  _LIBCPP_HIDE_FROM_ABI __iterator& operator=(__iterator&&) = default;
 
-  _LIBCPP_HIDE_FROM_ABI __basic_istream_view_iterator& operator++() {
+  _LIBCPP_HIDE_FROM_ABI __iterator& operator++() {
     *__parent_->__stream_ >> __parent_->__value_;
     return *this;
   }
@@ -92,7 +84,7 @@ public:
 
   _LIBCPP_HIDE_FROM_ABI _Val& operator*() const { return __parent_->__value_; }
 
-  _LIBCPP_HIDE_FROM_ABI friend bool operator==(const __basic_istream_view_iterator& __x, default_sentinel_t) {
+  _LIBCPP_HIDE_FROM_ABI friend bool operator==(const __iterator& __x, default_sentinel_t) {
     return !*__x.__get_parent_stream();
   }
 
lib/libcxx/include/__ranges/join_view.h
@@ -40,7 +40,10 @@
 
 _LIBCPP_BEGIN_NAMESPACE_STD
 
-#if _LIBCPP_STD_VER > 17
+// Note: `join_view` is still marked experimental because there is an ABI-breaking change that affects `join_view` in
+// the pipeline (https://isocpp.org/files/papers/D2770R0.html).
+// TODO: make `join_view` non-experimental once D2770 is implemented.
+#if _LIBCPP_STD_VER > 17 && defined(_LIBCPP_ENABLE_EXPERIMENTAL)
 
 namespace ranges {
   template<class>
@@ -66,14 +69,6 @@ namespace ranges {
     >;
   };
 
-  template <input_range _View, bool _Const>
-    requires view<_View> && input_range<range_reference_t<_View>>
-  struct __join_view_iterator;
-
-  template <input_range _View, bool _Const>
-    requires view<_View> && input_range<range_reference_t<_View>>
-  struct __join_view_sentinel;
-
   template<input_range _View>
     requires view<_View> && input_range<range_reference_t<_View>>
   class join_view
@@ -81,19 +76,9 @@ namespace ranges {
   private:
     using _InnerRange = range_reference_t<_View>;
 
-    template<bool _Const>
-    using __iterator = __join_view_iterator<_View, _Const>;
-
-    template<bool _Const>
-    using __sentinel = __join_view_sentinel<_View, _Const>;
+    template<bool> struct __iterator;
 
-    template <input_range _View2, bool _Const2>
-      requires view<_View2> && input_range<range_reference_t<_View2>>
-    friend struct __join_view_iterator;
-
-    template <input_range _View2, bool _Const2>
-      requires view<_View2> && input_range<range_reference_t<_View2>>
-    friend struct __join_view_sentinel;
+    template<bool> struct __sentinel;
 
     template <class>
     friend struct std::__segmented_iterator_traits;
@@ -164,12 +149,12 @@ namespace ranges {
     }
   };
 
-  template<input_range _View, bool _Const>
+  template<input_range _View>
     requires view<_View> && input_range<range_reference_t<_View>>
-  struct __join_view_sentinel {
-    template<input_range _View2, bool>
-      requires view<_View2> && input_range<range_reference_t<_View2>>
-    friend struct __join_view_sentinel;
+  template<bool _Const>
+  struct join_view<_View>::__sentinel {
+  template<bool>
+    friend struct __sentinel;
 
   private:
     using _Parent = __maybe_const<_Const, join_view<_View>>;
@@ -178,37 +163,42 @@ namespace ranges {
 
   public:
     _LIBCPP_HIDE_FROM_ABI
-    __join_view_sentinel() = default;
+    __sentinel() = default;
 
     _LIBCPP_HIDE_FROM_ABI
-    constexpr explicit __join_view_sentinel(_Parent& __parent)
+    constexpr explicit __sentinel(_Parent& __parent)
       : __end_(ranges::end(__parent.__base_)) {}
 
     _LIBCPP_HIDE_FROM_ABI
-    constexpr __join_view_sentinel(__join_view_sentinel<_View, !_Const> __s)
+    constexpr __sentinel(__sentinel<!_Const> __s)
       requires _Const && convertible_to<sentinel_t<_View>, sentinel_t<_Base>>
       : __end_(std::move(__s.__end_)) {}
 
     template<bool _OtherConst>
       requires sentinel_for<sentinel_t<_Base>, iterator_t<__maybe_const<_OtherConst, _View>>>
     _LIBCPP_HIDE_FROM_ABI
-    friend constexpr bool operator==(const __join_view_iterator<_View, _OtherConst>& __x, const __join_view_sentinel& __y) {
+    friend constexpr bool operator==(const __iterator<_OtherConst>& __x, const __sentinel& __y) {
       return __x.__outer_ == __y.__end_;
     }
   };
 
-  template<input_range _View, bool _Const>
+  // https://reviews.llvm.org/D142811#inline-1383022
+  // To simplify the segmented iterator traits specialization,
+  // make the iterator `final`
+  template<input_range _View>
     requires view<_View> && input_range<range_reference_t<_View>>
-  struct __join_view_iterator
+  template<bool _Const>
+  struct join_view<_View>::__iterator final
     : public __join_view_iterator_category<__maybe_const<_Const, _View>> {
 
-    template<input_range _View2, bool>
-      requires view<_View2> && input_range<range_reference_t<_View2>>
-    friend struct __join_view_iterator;
+    template<bool>
+    friend struct __iterator;
 
     template <class>
     friend struct std::__segmented_iterator_traits;
 
+    static constexpr bool __is_join_view_iterator = true;
+
   private:
     using _Parent = __maybe_const<_Const, join_view<_View>>;
     using _Base = __maybe_const<_Const, _View>;
@@ -243,7 +233,7 @@ namespace ranges {
         __inner_.reset();
     }
 
-    _LIBCPP_HIDE_FROM_ABI constexpr __join_view_iterator(_Parent* __parent, _Outer __outer, _Inner __inner)
+    _LIBCPP_HIDE_FROM_ABI constexpr __iterator(_Parent* __parent, _Outer __outer, _Inner __inner)
       : __outer_(std::move(__outer)), __inner_(std::move(__inner)), __parent_(__parent) {}
 
   public:
@@ -264,17 +254,17 @@ namespace ranges {
       range_difference_t<_Base>, range_difference_t<range_reference_t<_Base>>>;
 
     _LIBCPP_HIDE_FROM_ABI
-    __join_view_iterator() requires default_initializable<_Outer> = default;
+    __iterator() requires default_initializable<_Outer> = default;
 
     _LIBCPP_HIDE_FROM_ABI
-    constexpr __join_view_iterator(_Parent& __parent, _Outer __outer)
+    constexpr __iterator(_Parent& __parent, _Outer __outer)
       : __outer_(std::move(__outer))
       , __parent_(std::addressof(__parent)) {
       __satisfy();
     }
 
     _LIBCPP_HIDE_FROM_ABI
-    constexpr __join_view_iterator(__join_view_iterator<_View, !_Const> __i)
+    constexpr __iterator(__iterator<!_Const> __i)
       requires _Const &&
                convertible_to<iterator_t<_View>, _Outer> &&
                convertible_to<iterator_t<_InnerRange>, _Inner>
@@ -295,7 +285,7 @@ namespace ranges {
     }
 
     _LIBCPP_HIDE_FROM_ABI
-    constexpr __join_view_iterator& operator++() {
+    constexpr __iterator& operator++() {
       auto&& __inner = [&]() -> auto&& {
         if constexpr (__ref_is_glvalue)
           return *__outer_;
@@ -315,7 +305,7 @@ namespace ranges {
     }
 
     _LIBCPP_HIDE_FROM_ABI
-    constexpr __join_view_iterator operator++(int)
+    constexpr __iterator operator++(int)
       requires __ref_is_glvalue &&
                forward_range<_Base> &&
                forward_range<range_reference_t<_Base>>
@@ -326,7 +316,7 @@ namespace ranges {
     }
 
     _LIBCPP_HIDE_FROM_ABI
-    constexpr __join_view_iterator& operator--()
+    constexpr __iterator& operator--()
       requires __ref_is_glvalue &&
                bidirectional_range<_Base> &&
                bidirectional_range<range_reference_t<_Base>> &&
@@ -345,7 +335,7 @@ namespace ranges {
     }
 
     _LIBCPP_HIDE_FROM_ABI
-    constexpr __join_view_iterator operator--(int)
+    constexpr __iterator operator--(int)
       requires __ref_is_glvalue &&
                bidirectional_range<_Base> &&
                bidirectional_range<range_reference_t<_Base>> &&
@@ -357,7 +347,7 @@ namespace ranges {
     }
 
     _LIBCPP_HIDE_FROM_ABI
-    friend constexpr bool operator==(const __join_view_iterator& __x, const __join_view_iterator& __y)
+    friend constexpr bool operator==(const __iterator& __x, const __iterator& __y)
       requires __ref_is_glvalue &&
                equality_comparable<iterator_t<_Base>> &&
                equality_comparable<iterator_t<range_reference_t<_Base>>>
@@ -366,14 +356,14 @@ namespace ranges {
     }
 
     _LIBCPP_HIDE_FROM_ABI
-    friend constexpr decltype(auto) iter_move(const __join_view_iterator& __i)
+    friend constexpr decltype(auto) iter_move(const __iterator& __i)
       noexcept(noexcept(ranges::iter_move(*__i.__inner_)))
     {
       return ranges::iter_move(*__i.__inner_);
     }
 
     _LIBCPP_HIDE_FROM_ABI
-    friend constexpr void iter_swap(const __join_view_iterator& __x, const __join_view_iterator& __y)
+    friend constexpr void iter_swap(const __iterator& __x, const __iterator& __y)
       noexcept(noexcept(ranges::iter_swap(*__x.__inner_, *__y.__inner_)))
       requires indirectly_swappable<_Inner>
     {
@@ -401,12 +391,12 @@ inline namespace __cpo {
 } // namespace views
 } // namespace ranges
 
-template <class _View, bool _Const>
-  requires(ranges::common_range<typename ranges::__join_view_iterator<_View, _Const>::_Parent> &&
-           __is_cpp17_random_access_iterator<typename ranges::__join_view_iterator<_View, _Const>::_Outer>::value &&
-           __is_cpp17_random_access_iterator<typename ranges::__join_view_iterator<_View, _Const>::_Inner>::value)
-struct __segmented_iterator_traits<ranges::__join_view_iterator<_View, _Const>> {
-  using _JoinViewIterator = ranges::__join_view_iterator<_View, _Const>;
+template <class _JoinViewIterator>
+  requires(_JoinViewIterator::__is_join_view_iterator &&
+           ranges::common_range<typename _JoinViewIterator::_Parent> &&
+           __is_cpp17_random_access_iterator<typename _JoinViewIterator::_Outer>::value &&
+           __is_cpp17_random_access_iterator<typename _JoinViewIterator::_Inner>::value)
+struct __segmented_iterator_traits<_JoinViewIterator> {
 
   using __segment_iterator =
       _LIBCPP_NODEBUG __iterator_with_data<typename _JoinViewIterator::_Outer, typename _JoinViewIterator::_Parent*>;
@@ -445,7 +435,7 @@ struct __segmented_iterator_traits<ranges::__join_view_iterator<_View, _Const>>
   }
 };
 
-#endif // _LIBCPP_STD_VER > 17
+#endif // #if _LIBCPP_STD_VER > 17 && defined(_LIBCPP_ENABLE_EXPERIMENTAL)
 
 _LIBCPP_END_NAMESPACE_STD
 
lib/libcxx/include/__ranges/split_view.h
@@ -42,12 +42,6 @@ _LIBCPP_BEGIN_NAMESPACE_STD
 
 namespace ranges {
 
-template <class _View, class _Pattern>
-struct __split_view_iterator;
-
-template <class _View, class _Pattern>
-struct __split_view_sentinel;
-
 template <forward_range _View, forward_range _Pattern>
   requires view<_View> && view<_Pattern> &&
            indirectly_comparable<iterator_t<_View>, iterator_t<_Pattern>, ranges::equal_to>
@@ -59,13 +53,13 @@ private:
   _Cache __cached_begin_                        = _Cache();
 
   template <class, class>
-  friend struct __split_view_iterator;
+  friend struct __iterator;
 
   template <class, class>
-  friend struct __split_view_sentinel;
+  friend struct __sentinel;
 
-  using __iterator = __split_view_iterator<_View, _Pattern>;
-  using __sentinel = __split_view_sentinel<_View, _Pattern>;
+  struct __iterator;
+  struct __sentinel;
 
   _LIBCPP_HIDE_FROM_ABI constexpr subrange<iterator_t<_View>> __find_next(iterator_t<_View> __it) {
     auto [__begin, __end] = ranges::search(subrange(__it, ranges::end(__base_)), __pattern_);
@@ -120,16 +114,17 @@ split_view(_Range&&, _Pattern&&) -> split_view<views::all_t<_Range>, views::all_
 template <forward_range _Range>
 split_view(_Range&&, range_value_t<_Range>) -> split_view<views::all_t<_Range>, single_view<range_value_t<_Range>>>;
 
-template <class _View, class _Pattern>
-struct __split_view_iterator {
+template <forward_range _View, forward_range _Pattern>
+  requires view<_View> && view<_Pattern> &&
+           indirectly_comparable<iterator_t<_View>, iterator_t<_Pattern>, ranges::equal_to>
+struct split_view<_View, _Pattern>::__iterator {
 private:
-  split_view<_View, _Pattern>* __parent_                        = nullptr;
+  split_view* __parent_                                         = nullptr;
   _LIBCPP_NO_UNIQUE_ADDRESS iterator_t<_View> __cur_            = iterator_t<_View>();
   _LIBCPP_NO_UNIQUE_ADDRESS subrange<iterator_t<_View>> __next_ = subrange<iterator_t<_View>>();
   bool __trailing_empty_                                        = false;
 
-  template <class, class>
-  friend struct __split_view_sentinel;
+  friend struct __sentinel;
 
 public:
   using iterator_concept  = forward_iterator_tag;
@@ -137,9 +132,9 @@ public:
   using value_type        = subrange<iterator_t<_View>>;
   using difference_type   = range_difference_t<_View>;
 
-  _LIBCPP_HIDE_FROM_ABI __split_view_iterator() = default;
+  _LIBCPP_HIDE_FROM_ABI __iterator() = default;
 
-  _LIBCPP_HIDE_FROM_ABI constexpr __split_view_iterator(
+  _LIBCPP_HIDE_FROM_ABI constexpr __iterator(
       split_view<_View, _Pattern>& __parent, iterator_t<_View> __current, subrange<iterator_t<_View>> __next)
       : __parent_(std::addressof(__parent)), __cur_(std::move(__current)), __next_(std::move(__next)) {}
 
@@ -147,7 +142,7 @@ public:
 
   _LIBCPP_HIDE_FROM_ABI constexpr value_type operator*() const { return {__cur_, __next_.begin()}; }
 
-  _LIBCPP_HIDE_FROM_ABI constexpr __split_view_iterator& operator++() {
+  _LIBCPP_HIDE_FROM_ABI constexpr __iterator& operator++() {
     __cur_ = __next_.begin();
     if (__cur_ != ranges::end(__parent_->__base_)) {
       __cur_ = __next_.end();
@@ -163,36 +158,35 @@ public:
     return *this;
   }
 
-  _LIBCPP_HIDE_FROM_ABI constexpr __split_view_iterator operator++(int) {
+  _LIBCPP_HIDE_FROM_ABI constexpr __iterator operator++(int) {
     auto __tmp = *this;
     ++*this;
     return __tmp;
   }
 
-  _LIBCPP_HIDE_FROM_ABI friend constexpr bool
-  operator==(const __split_view_iterator& __x, const __split_view_iterator& __y) {
+  _LIBCPP_HIDE_FROM_ABI friend constexpr bool operator==(const __iterator& __x, const __iterator& __y) {
     return __x.__cur_ == __y.__cur_ && __x.__trailing_empty_ == __y.__trailing_empty_;
   }
 };
 
-template <class _View, class _Pattern>
-struct __split_view_sentinel {
+template <forward_range _View, forward_range _Pattern>
+  requires view<_View> && view<_Pattern> &&
+           indirectly_comparable<iterator_t<_View>, iterator_t<_Pattern>, ranges::equal_to>
+struct split_view<_View, _Pattern>::__sentinel {
 private:
   _LIBCPP_NO_UNIQUE_ADDRESS sentinel_t<_View> __end_ = sentinel_t<_View>();
 
-  _LIBCPP_HIDE_FROM_ABI static constexpr bool
-  __equals(const __split_view_iterator<_View, _Pattern>& __x, const __split_view_sentinel& __y) {
+  _LIBCPP_HIDE_FROM_ABI static constexpr bool __equals(const __iterator& __x, const __sentinel& __y) {
     return __x.__cur_ == __y.__end_ && !__x.__trailing_empty_;
   }
 
 public:
-  _LIBCPP_HIDE_FROM_ABI __split_view_sentinel() = default;
+  _LIBCPP_HIDE_FROM_ABI __sentinel() = default;
 
-  _LIBCPP_HIDE_FROM_ABI constexpr explicit __split_view_sentinel(split_view<_View, _Pattern>& __parent)
+  _LIBCPP_HIDE_FROM_ABI constexpr explicit __sentinel(split_view<_View, _Pattern>& __parent)
       : __end_(ranges::end(__parent.__base_)) {}
 
-  _LIBCPP_HIDE_FROM_ABI friend constexpr bool
-  operator==(const __split_view_iterator<_View, _Pattern>& __x, const __split_view_sentinel& __y) {
+  _LIBCPP_HIDE_FROM_ABI friend constexpr bool operator==(const __iterator& __x, const __sentinel& __y) {
     return __equals(__x, __y);
   }
 };
lib/libcxx/include/__ranges/take_while_view.h
@@ -53,17 +53,11 @@ template <class _View, class _Pred>
 concept __take_while_const_is_range =
     range<const _View> && indirect_unary_predicate<const _Pred, iterator_t<const _View>>;
 
-template <class, class, bool>
-class __take_while_view_sentinel;
-
 template <view _View, class _Pred>
   requires input_range<_View> && is_object_v<_Pred> && indirect_unary_predicate<const _Pred, iterator_t<_View>>
 class take_while_view : public view_interface<take_while_view<_View, _Pred>> {
-  template <class, class, bool>
-  friend class __take_while_view_sentinel;
-
-  template <bool _Const>
-  using __sentinel = __take_while_view_sentinel<_View, _Pred, _Const>;
+  template <bool>
+  class __sentinel;
 
   _LIBCPP_NO_UNIQUE_ADDRESS _View __base_ = _View();
   _LIBCPP_NO_UNIQUE_ADDRESS __copyable_box<_Pred> __pred_;
@@ -114,37 +108,37 @@ public:
 template <class _Range, class _Pred>
 take_while_view(_Range&&, _Pred) -> take_while_view<views::all_t<_Range>, _Pred>;
 
-template <class _View, class _Pred, bool _Const>
-class __take_while_view_sentinel {
+template <view _View, class _Pred>
+  requires input_range<_View> && is_object_v<_Pred> && indirect_unary_predicate<const _Pred, iterator_t<_View>>
+template <bool _Const>
+class take_while_view<_View, _Pred>::__sentinel {
   using _Base = __maybe_const<_Const, _View>;
 
   sentinel_t<_Base> __end_ = sentinel_t<_Base>();
   const _Pred* __pred_     = nullptr;
 
-  template <class, class, bool>
-  friend class __take_while_view_sentinel;
+  friend class __sentinel<!_Const>;
 
 public:
-  _LIBCPP_HIDE_FROM_ABI __take_while_view_sentinel() = default;
+  _LIBCPP_HIDE_FROM_ABI __sentinel() = default;
 
-  _LIBCPP_HIDE_FROM_ABI constexpr explicit __take_while_view_sentinel(sentinel_t<_Base> __end, const _Pred* __pred)
+  _LIBCPP_HIDE_FROM_ABI constexpr explicit __sentinel(sentinel_t<_Base> __end, const _Pred* __pred)
       : __end_(std::move(__end)), __pred_(__pred) {}
 
-  _LIBCPP_HIDE_FROM_ABI constexpr __take_while_view_sentinel(__take_while_view_sentinel<_View, _Pred, !_Const> __s)
+  _LIBCPP_HIDE_FROM_ABI constexpr __sentinel(__sentinel<!_Const> __s)
     requires _Const && convertible_to<sentinel_t<_View>, sentinel_t<_Base>>
       : __end_(std::move(__s.__end_)), __pred_(__s.__pred_) {}
 
   _LIBCPP_HIDE_FROM_ABI constexpr sentinel_t<_Base> base() const { return __end_; }
 
-  _LIBCPP_HIDE_FROM_ABI friend constexpr bool
-  operator==(const iterator_t<_Base>& __x, const __take_while_view_sentinel& __y) {
+  _LIBCPP_HIDE_FROM_ABI friend constexpr bool operator==(const iterator_t<_Base>& __x, const __sentinel& __y) {
     return __x == __y.__end_ || !std::invoke(*__y.__pred_, *__x);
   }
 
   template <bool _OtherConst = !_Const>
     requires sentinel_for<sentinel_t<_Base>, iterator_t<__maybe_const<_OtherConst, _View>>>
   _LIBCPP_HIDE_FROM_ABI friend constexpr bool
-  operator==(const iterator_t<__maybe_const<_OtherConst, _View>>& __x, const __take_while_view_sentinel& __y) {
+  operator==(const iterator_t<__maybe_const<_OtherConst, _View>>& __x, const __sentinel& __y) {
     return __x == __y.__end_ || !std::invoke(*__y.__pred_, *__x);
   }
 };
lib/libcxx/include/__ranges/transform_view.h
@@ -57,31 +57,11 @@ concept __transform_view_constraints =
   regular_invocable<_Fn&, range_reference_t<_View>> &&
   __can_reference<invoke_result_t<_Fn&, range_reference_t<_View>>>;
 
-template <input_range _View, copy_constructible _Function, bool _IsConst>
-  requires __transform_view_constraints<_View, _Function>
-class __transform_view_iterator;
-
-template <input_range _View, copy_constructible _Function, bool _IsConst>
-  requires __transform_view_constraints<_View, _Function>
-class __transform_view_sentinel;
-
 template<input_range _View, copy_constructible _Fn>
   requires __transform_view_constraints<_View, _Fn>
 class transform_view : public view_interface<transform_view<_View, _Fn>> {
-
-  template <bool _IsConst>
-  using __iterator = __transform_view_iterator<_View, _Fn, _IsConst>;
-
-  template <bool _IsConst>
-  using __sentinel = __transform_view_sentinel<_View, _Fn, _IsConst>;
-
-  template <input_range _ViewType, copy_constructible _FunctionType, bool _IsConst>
-    requires __transform_view_constraints<_ViewType, _FunctionType>
-  friend class __transform_view_iterator;
-
-  template <input_range _ViewType, copy_constructible _FunctionType, bool _IsConst>
-    requires __transform_view_constraints<_ViewType, _FunctionType>
-  friend class __transform_view_sentinel;
+  template<bool> class __iterator;
+  template<bool> class __sentinel;
 
   _LIBCPP_NO_UNIQUE_ADDRESS __copyable_box<_Fn> __func_;
   _LIBCPP_NO_UNIQUE_ADDRESS _View __base_ = _View();
@@ -176,23 +156,22 @@ struct __transform_view_iterator_category_base<_View, _Fn> {
   >;
 };
 
-template<input_range _View, copy_constructible _Fn, bool _Const>
+template<input_range _View, copy_constructible _Fn>
   requires __transform_view_constraints<_View, _Fn>
-class __transform_view_iterator
+template<bool _Const>
+class transform_view<_View, _Fn>::__iterator
   : public __transform_view_iterator_category_base<_View, _Fn> {
 
-  using _Parent = __maybe_const<_Const, transform_view<_View, _Fn>>;
+  using _Parent = __maybe_const<_Const, transform_view>;
   using _Base = __maybe_const<_Const, _View>;
 
   _Parent *__parent_ = nullptr;
 
-  template<input_range _ViewType, copy_constructible _FunctionType, bool _IsConst>
-    requires __transform_view_constraints<_ViewType, _FunctionType>
-  friend class __transform_view_iterator;
+  template<bool>
+  friend class transform_view<_View, _Fn>::__iterator;
 
-  template<input_range _ViewType, copy_constructible _FunctionType, bool _IsConst>
-    requires __transform_view_constraints<_ViewType, _FunctionType>
-  friend class __transform_view_sentinel;
+  template<bool>
+  friend class transform_view<_View, _Fn>::__sentinel;
 
 public:
   iterator_t<_Base> __current_ = iterator_t<_Base>();
@@ -202,17 +181,17 @@ public:
   using difference_type = range_difference_t<_Base>;
 
   _LIBCPP_HIDE_FROM_ABI
-  __transform_view_iterator() requires default_initializable<iterator_t<_Base>> = default;
+  __iterator() requires default_initializable<iterator_t<_Base>> = default;
 
   _LIBCPP_HIDE_FROM_ABI
-  constexpr __transform_view_iterator(_Parent& __parent, iterator_t<_Base> __current)
+  constexpr __iterator(_Parent& __parent, iterator_t<_Base> __current)
     : __parent_(std::addressof(__parent)), __current_(std::move(__current)) {}
 
-  // Note: `__i` should always be `__transform_view_iterator<false>`, but directly using
-  // `__transform_view_iterator<false>` is ill-formed when `_Const` is false
+  // Note: `__i` should always be `__iterator<false>`, but directly using
+  // `__iterator<false>` is ill-formed when `_Const` is false
   // (see http://wg21.link/class.copy.ctor#5).
   _LIBCPP_HIDE_FROM_ABI
-  constexpr __transform_view_iterator(__transform_view_iterator<_View, _Fn, !_Const> __i)
+  constexpr __iterator(__iterator<!_Const> __i)
     requires _Const && convertible_to<iterator_t<_View>, iterator_t<_Base>>
     : __parent_(__i.__parent_), __current_(std::move(__i.__current_)) {}
 
@@ -234,7 +213,7 @@ public:
   }
 
   _LIBCPP_HIDE_FROM_ABI
-  constexpr __transform_view_iterator& operator++() {
+  constexpr __iterator& operator++() {
     ++__current_;
     return *this;
   }
@@ -243,7 +222,7 @@ public:
   constexpr void operator++(int) { ++__current_; }
 
   _LIBCPP_HIDE_FROM_ABI
-  constexpr __transform_view_iterator operator++(int)
+  constexpr __iterator operator++(int)
     requires forward_range<_Base>
   {
     auto __tmp = *this;
@@ -252,7 +231,7 @@ public:
   }
 
   _LIBCPP_HIDE_FROM_ABI
-  constexpr __transform_view_iterator& operator--()
+  constexpr __iterator& operator--()
     requires bidirectional_range<_Base>
   {
     --__current_;
@@ -260,7 +239,7 @@ public:
   }
 
   _LIBCPP_HIDE_FROM_ABI
-  constexpr __transform_view_iterator operator--(int)
+  constexpr __iterator operator--(int)
     requires bidirectional_range<_Base>
   {
     auto __tmp = *this;
@@ -269,7 +248,7 @@ public:
   }
 
   _LIBCPP_HIDE_FROM_ABI
-  constexpr __transform_view_iterator& operator+=(difference_type __n)
+  constexpr __iterator& operator+=(difference_type __n)
     requires random_access_range<_Base>
   {
     __current_ += __n;
@@ -277,7 +256,7 @@ public:
   }
 
   _LIBCPP_HIDE_FROM_ABI
-  constexpr __transform_view_iterator& operator-=(difference_type __n)
+  constexpr __iterator& operator-=(difference_type __n)
     requires random_access_range<_Base>
   {
     __current_ -= __n;
@@ -293,77 +272,77 @@ public:
   }
 
   _LIBCPP_HIDE_FROM_ABI
-  friend constexpr bool operator==(const __transform_view_iterator& __x, const __transform_view_iterator& __y)
+  friend constexpr bool operator==(const __iterator& __x, const __iterator& __y)
     requires equality_comparable<iterator_t<_Base>>
   {
     return __x.__current_ == __y.__current_;
   }
 
   _LIBCPP_HIDE_FROM_ABI
-  friend constexpr bool operator<(const __transform_view_iterator& __x, const __transform_view_iterator& __y)
+  friend constexpr bool operator<(const __iterator& __x, const __iterator& __y)
     requires random_access_range<_Base>
   {
     return __x.__current_ < __y.__current_;
   }
 
   _LIBCPP_HIDE_FROM_ABI
-  friend constexpr bool operator>(const __transform_view_iterator& __x, const __transform_view_iterator& __y)
+  friend constexpr bool operator>(const __iterator& __x, const __iterator& __y)
     requires random_access_range<_Base>
   {
     return __x.__current_ > __y.__current_;
   }
 
   _LIBCPP_HIDE_FROM_ABI
-  friend constexpr bool operator<=(const __transform_view_iterator& __x, const __transform_view_iterator& __y)
+  friend constexpr bool operator<=(const __iterator& __x, const __iterator& __y)
     requires random_access_range<_Base>
   {
     return __x.__current_ <= __y.__current_;
   }
 
   _LIBCPP_HIDE_FROM_ABI
-  friend constexpr bool operator>=(const __transform_view_iterator& __x, const __transform_view_iterator& __y)
+  friend constexpr bool operator>=(const __iterator& __x, const __iterator& __y)
     requires random_access_range<_Base>
   {
     return __x.__current_ >= __y.__current_;
   }
 
   _LIBCPP_HIDE_FROM_ABI
-  friend constexpr auto operator<=>(const __transform_view_iterator& __x, const __transform_view_iterator& __y)
+  friend constexpr auto operator<=>(const __iterator& __x, const __iterator& __y)
     requires random_access_range<_Base> && three_way_comparable<iterator_t<_Base>>
   {
     return __x.__current_ <=> __y.__current_;
   }
 
   _LIBCPP_HIDE_FROM_ABI
-  friend constexpr __transform_view_iterator operator+(__transform_view_iterator __i, difference_type __n)
+  friend constexpr __iterator operator+(__iterator __i, difference_type __n)
     requires random_access_range<_Base>
   {
-    return __transform_view_iterator{*__i.__parent_, __i.__current_ + __n};
+    return __iterator{*__i.__parent_, __i.__current_ + __n};
   }
 
   _LIBCPP_HIDE_FROM_ABI
-  friend constexpr __transform_view_iterator operator+(difference_type __n, __transform_view_iterator __i)
+  friend constexpr __iterator operator+(difference_type __n, __iterator __i)
     requires random_access_range<_Base>
   {
-    return __transform_view_iterator{*__i.__parent_, __i.__current_ + __n};
+    return __iterator{*__i.__parent_, __i.__current_ + __n};
   }
 
   _LIBCPP_HIDE_FROM_ABI
-  friend constexpr __transform_view_iterator operator-(__transform_view_iterator __i, difference_type __n)
+  friend constexpr __iterator operator-(__iterator __i, difference_type __n)
     requires random_access_range<_Base>
   {
-    return __transform_view_iterator{*__i.__parent_, __i.__current_ - __n};
+    return __iterator{*__i.__parent_, __i.__current_ - __n};
   }
 
   _LIBCPP_HIDE_FROM_ABI
-  friend constexpr difference_type operator-(const __transform_view_iterator& __x, const __transform_view_iterator& __y)
+  friend constexpr difference_type operator-(const __iterator& __x, const __iterator& __y)
     requires sized_sentinel_for<iterator_t<_Base>, iterator_t<_Base>>
   {
     return __x.__current_ - __y.__current_;
   }
 
   _LIBCPP_HIDE_FROM_ABI
-  friend constexpr decltype(auto) iter_move(const __transform_view_iterator& __i)
+  friend constexpr decltype(auto) iter_move(const __iterator& __i)
     noexcept(noexcept(*__i))
   {
     if constexpr (is_lvalue_reference_v<decltype(*__i)>)
@@ -373,37 +352,33 @@ public:
   }
 };
 
-template<input_range _View, copy_constructible _Fn, bool _Const>
+template<input_range _View, copy_constructible _Fn>
   requires __transform_view_constraints<_View, _Fn>
-class __transform_view_sentinel {
-  using _Parent = __maybe_const<_Const, transform_view<_View, _Fn>>;
+template<bool _Const>
+class transform_view<_View, _Fn>::__sentinel {
+  using _Parent = __maybe_const<_Const, transform_view>;
   using _Base = __maybe_const<_Const, _View>;
 
-  template <bool _IsConst>
-  using __iterator = __transform_view_iterator<_View, _Fn, _IsConst>;
-
   sentinel_t<_Base> __end_ = sentinel_t<_Base>();
 
-  template<input_range _ViewType, copy_constructible _FunctionType, bool _IsConst>
-    requires __transform_view_constraints<_ViewType, _FunctionType>
-  friend class __transform_view_iterator;
+  template<bool>
+  friend class transform_view<_View, _Fn>::__iterator;
 
-  template<input_range _ViewType, copy_constructible _FunctionType, bool _IsConst>
-    requires __transform_view_constraints<_ViewType, _FunctionType>
-  friend class __transform_view_sentinel;
+  template<bool>
+  friend class transform_view<_View, _Fn>::__sentinel;
 
 public:
   _LIBCPP_HIDE_FROM_ABI
-  __transform_view_sentinel() = default;
+  __sentinel() = default;
 
   _LIBCPP_HIDE_FROM_ABI
-  constexpr explicit __transform_view_sentinel(sentinel_t<_Base> __end) : __end_(__end) {}
+  constexpr explicit __sentinel(sentinel_t<_Base> __end) : __end_(__end) {}
 
-  // Note: `__i` should always be `__transform_view_sentinel<false>`, but directly using
-  // `__transform_view_sentinel<false>` is ill-formed when `_Const` is false
+  // Note: `__i` should always be `__sentinel<false>`, but directly using
+  // `__sentinel<false>` is ill-formed when `_Const` is false
   // (see http://wg21.link/class.copy.ctor#5).
   _LIBCPP_HIDE_FROM_ABI
-  constexpr __transform_view_sentinel(__transform_view_sentinel<_View, _Fn, !_Const> __i)
+  constexpr __sentinel(__sentinel<!_Const> __i)
     requires _Const && convertible_to<sentinel_t<_View>, sentinel_t<_Base>>
     : __end_(std::move(__i.__end_)) {}
 
@@ -413,7 +388,7 @@ public:
   template<bool _OtherConst>
     requires sentinel_for<sentinel_t<_Base>, iterator_t<__maybe_const<_OtherConst, _View>>>
   _LIBCPP_HIDE_FROM_ABI
-  friend constexpr bool operator==(const __iterator<_OtherConst>& __x, const __transform_view_sentinel& __y) {
+  friend constexpr bool operator==(const __iterator<_OtherConst>& __x, const __sentinel& __y) {
     return __x.__current_ == __y.__end_;
   }
 
@@ -421,7 +396,7 @@ public:
     requires sized_sentinel_for<sentinel_t<_Base>, iterator_t<__maybe_const<_OtherConst, _View>>>
   _LIBCPP_HIDE_FROM_ABI
   friend constexpr range_difference_t<__maybe_const<_OtherConst, _View>>
-  operator-(const __iterator<_OtherConst>& __x, const __transform_view_sentinel& __y) {
+  operator-(const __iterator<_OtherConst>& __x, const __sentinel& __y) {
     return __x.__current_ - __y.__end_;
   }
 
@@ -429,7 +404,7 @@ public:
     requires sized_sentinel_for<sentinel_t<_Base>, iterator_t<__maybe_const<_OtherConst, _View>>>
   _LIBCPP_HIDE_FROM_ABI
   friend constexpr range_difference_t<__maybe_const<_OtherConst, _View>>
-  operator-(const __transform_view_sentinel& __x, const __iterator<_OtherConst>& __y) {
+  operator-(const __sentinel& __x, const __iterator<_OtherConst>& __y) {
     return __x.__end_ - __y.__current_;
   }
 };
lib/libcxx/include/__type_traits/add_pointer.h
@@ -22,7 +22,7 @@
 
 _LIBCPP_BEGIN_NAMESPACE_STD
 
-#if __has_builtin(__add_pointer)
+#if !defined(_LIBCPP_WORKAROUND_OBJCXX_COMPILER_INTRINSICS) && __has_builtin(__add_pointer)
 
 template <class _Tp>
 using __add_pointer_t = __add_pointer(_Tp);
@@ -39,7 +39,7 @@ template <class _Tp> struct __add_pointer_impl<_Tp, false>
 template <class _Tp>
 using __add_pointer_t = typename __add_pointer_impl<_Tp>::type;
 
-#endif // __has_builtin(__add_pointer)
+#endif // !defined(_LIBCPP_WORKAROUND_OBJCXX_COMPILER_INTRINSICS) && __has_builtin(__add_pointer)
 
 template <class _Tp>
 struct add_pointer {
lib/libcxx/include/__type_traits/remove_pointer.h
@@ -17,7 +17,7 @@
 
 _LIBCPP_BEGIN_NAMESPACE_STD
 
-#if __has_builtin(__remove_pointer)
+#if !defined(_LIBCPP_WORKAROUND_OBJCXX_COMPILER_INTRINSICS) && __has_builtin(__remove_pointer)
 template <class _Tp>
 struct remove_pointer {
   using type _LIBCPP_NODEBUG = __remove_pointer(_Tp);
@@ -34,7 +34,7 @@ template <class _Tp> struct _LIBCPP_TEMPLATE_VIS remove_pointer<_Tp* const volat
 
 template <class _Tp>
 using __remove_pointer_t = typename remove_pointer<_Tp>::type;
-#endif // __has_builtin(__remove_pointer)
+#endif // !defined(_LIBCPP_WORKAROUND_OBJCXX_COMPILER_INTRINSICS) && __has_builtin(__remove_pointer)
 
 #if _LIBCPP_STD_VER > 11
 template <class _Tp> using remove_pointer_t = __remove_pointer_t<_Tp>;
lib/libcxx/include/__config
@@ -134,6 +134,15 @@
 #    define _LIBCPP_ABI_DO_NOT_EXPORT_VECTOR_BASE_COMMON
 // According to the Standard, `bitset::operator[] const` returns bool
 #    define _LIBCPP_ABI_BITSET_VECTOR_BOOL_CONST_SUBSCRIPT_RETURN_BOOL
+// Fix the implementation of CityHash used for std::hash<fundamental-type>.
+// This is an ABI break because `std::hash` will return a different result,
+// which means that hashing the same object in translation units built against
+// different versions of libc++ can return inconsistent results. This is especially
+// tricky since std::hash is used in the implementation of unordered containers.
+//
+// The incorrect implementation of CityHash has the problem that it drops some
+// bits on the floor.
+#    define _LIBCPP_ABI_FIX_CITYHASH_IMPLEMENTATION
 // Remove the base 10 implementation of std::to_chars from the dylib.
 // The implementation moved to the header, but we still export the symbols from
 // the dylib for backwards compatibility.
@@ -895,7 +904,7 @@ _LIBCPP_BEGIN_NAMESPACE_STD _LIBCPP_END_NAMESPACE_STD
 
 // Try to find out if RTTI is disabled.
 #  if !defined(__cpp_rtti) || __cpp_rtti < 199711L
-#    define _LIBCPP_NO_RTTI
+#    define _LIBCPP_HAS_NO_RTTI
 #  endif
 
 #  ifndef _LIBCPP_WEAK
@@ -1227,12 +1236,12 @@ _LIBCPP_BEGIN_NAMESPACE_STD _LIBCPP_END_NAMESPACE_STD
 // functions are declared by the C library.
 #  define _LIBCPP_HAS_NO_C8RTOMB_MBRTOC8
 // GNU libc 2.36 and newer declare c8rtomb() and mbrtoc8() in C++ modes if
-// __cpp_char8_t is defined or if C2X extensions are enabled. Unfortunately,
-// determining the latter depends on internal GNU libc details. If the
-// __cpp_char8_t feature test macro is not defined, then a char8_t typedef
-// will be declared as well.
-#  if defined(_LIBCPP_GLIBC_PREREQ) && defined(__GLIBC_USE)
-#    if _LIBCPP_GLIBC_PREREQ(2, 36) && (defined(__cpp_char8_t) || __GLIBC_USE(ISOC2X))
+// __cpp_char8_t is defined or if C2X extensions are enabled. Determining
+// the latter depends on internal GNU libc details that are not appropriate
+// to depend on here, so any declarations present when __cpp_char8_t is not
+// defined are ignored.
+#  if defined(_LIBCPP_GLIBC_PREREQ)
+#    if _LIBCPP_GLIBC_PREREQ(2, 36) && defined(__cpp_char8_t)
 #      undef _LIBCPP_HAS_NO_C8RTOMB_MBRTOC8
 #    endif
 #  endif
@@ -1250,6 +1259,12 @@ _LIBCPP_BEGIN_NAMESPACE_STD _LIBCPP_END_NAMESPACE_STD
 #  define _LIBCPP_CTAD_SUPPORTED_FOR_TYPE(_ClassName) static_assert(true, "")
 #endif
 
+// TODO(varconst): currently, there are bugs in Clang's intrinsics when handling Objective-C++ `id`, so don't use
+// compiler intrinsics in the Objective-C++ mode.
+#  ifdef __OBJC__
+#    define _LIBCPP_WORKAROUND_OBJCXX_COMPILER_INTRINSICS
+#  endif
+
 #endif // __cplusplus
 
 #endif // _LIBCPP___CONFIG
lib/libcxx/include/any
@@ -175,7 +175,7 @@ namespace __any_imp
   inline _LIBCPP_INLINE_VISIBILITY
   bool __compare_typeid(type_info const* __id, const void* __fallback_id)
   {
-#if !defined(_LIBCPP_NO_RTTI)
+#if !defined(_LIBCPP_HAS_NO_RTTI)
       if (__id && *__id == typeid(_Tp))
           return true;
 #endif
@@ -294,7 +294,7 @@ public:
   _LIBCPP_INLINE_VISIBILITY
   bool has_value() const _NOEXCEPT { return __h_ != nullptr; }
 
-#if !defined(_LIBCPP_NO_RTTI)
+#if !defined(_LIBCPP_HAS_NO_RTTI)
   _LIBCPP_INLINE_VISIBILITY
   const type_info & type() const _NOEXCEPT {
     if (__h_) {
@@ -426,7 +426,7 @@ namespace __any_imp
     _LIBCPP_INLINE_VISIBILITY
     static void* __type_info()
     {
-#if !defined(_LIBCPP_NO_RTTI)
+#if !defined(_LIBCPP_HAS_NO_RTTI)
         return const_cast<void*>(static_cast<void const *>(&typeid(_Tp)));
 #else
         return nullptr;
@@ -514,7 +514,7 @@ namespace __any_imp
     _LIBCPP_INLINE_VISIBILITY
     static void* __type_info()
     {
-#if !defined(_LIBCPP_NO_RTTI)
+#if !defined(_LIBCPP_HAS_NO_RTTI)
         return const_cast<void*>(static_cast<void const *>(&typeid(_Tp)));
 #else
         return nullptr;
@@ -680,7 +680,7 @@ any_cast(any * __any) _NOEXCEPT
     typedef add_pointer_t<_ValueType> _ReturnType;
     if (__any && __any->__h_) {
       void *__p = __any->__call(_Action::_Get, nullptr,
-#if !defined(_LIBCPP_NO_RTTI)
+#if !defined(_LIBCPP_HAS_NO_RTTI)
                           &typeid(_ValueType),
 #else
                           nullptr,
lib/libcxx/include/version
@@ -139,6 +139,7 @@ __cpp_lib_polymorphic_allocator                         201902L <memory_resource
 __cpp_lib_quoted_string_io                              201304L <iomanip>
 __cpp_lib_ranges                                        202106L <algorithm> <functional> <iterator>
                                                                 <memory> <ranges>
+__cpp_lib_ranges_as_rvalue                              202207L <ranges>
 __cpp_lib_ranges_chunk                                  202202L <ranges>
 __cpp_lib_ranges_chunk_by                               202202L <ranges>
 __cpp_lib_ranges_iota                                   202202L <numeric>
@@ -401,6 +402,7 @@ __cpp_lib_void_t                                        201411L <type_traits>
 # undef  __cpp_lib_optional
 # define __cpp_lib_optional                             202110L
 // # define __cpp_lib_out_ptr                              202106L
+# define __cpp_lib_ranges_as_rvalue                     202207L
 // # define __cpp_lib_ranges_chunk                         202202L
 // # define __cpp_lib_ranges_chunk_by                      202202L
 // # define __cpp_lib_ranges_iota                          202202L