Upd libc++ to d0af4276d62418ba9e54fec99b293d2fd7c92213 (14 Mar 2022)

21 files changed, 84 insertions, 74 deletions

diff --git a/contrib/libs/cxxsupp/libcxx/include/__iterator/advance.h b/contrib/libs/cxxsupp/libcxx/include/__iterator/advance.h
index 1e49676ce7..9a74f1421c 100644
--- a/contrib/libs/cxxsupp/libcxx/include/__iterator/advance.h
+++ b/contrib/libs/cxxsupp/libcxx/include/__iterator/advance.h
@@ -65,7 +65,7 @@ void advance(_InputIter& __i, _Distance __orig_n) {
   _VSTD::__advance(__i, __n, typename iterator_traits<_InputIter>::iterator_category());
 }
 
-#if !defined(_LIBCPP_HAS_NO_CONCEPTS) && !defined(_LIBCPP_HAS_NO_INCOMPLETE_RANGES)
+#if _LIBCPP_STD_VER > 17 && !defined(_LIBCPP_HAS_NO_INCOMPLETE_RANGES)
 
 // [range.iter.op.advance]
 
@@ -193,7 +193,7 @@ inline namespace __cpo {
 } // namespace __cpo
 } // namespace ranges
 
-#endif // !defined(_LIBCPP_HAS_NO_CONCEPTS) && !defined(_LIBCPP_HAS_NO_INCOMPLETE_RANGES)
+#endif // _LIBCPP_STD_VER > 17 && !defined(_LIBCPP_HAS_NO_INCOMPLETE_RANGES)
 
 _LIBCPP_END_NAMESPACE_STD
 
diff --git a/contrib/libs/cxxsupp/libcxx/include/__iterator/common_iterator.h b/contrib/libs/cxxsupp/libcxx/include/__iterator/common_iterator.h
index abbd8f4038..abcc0b675e 100644
--- a/contrib/libs/cxxsupp/libcxx/include/__iterator/common_iterator.h
+++ b/contrib/libs/cxxsupp/libcxx/include/__iterator/common_iterator.h
@@ -27,7 +27,7 @@
 
 _LIBCPP_BEGIN_NAMESPACE_STD
 
-#if !defined(_LIBCPP_HAS_NO_CONCEPTS)
+#if _LIBCPP_STD_VER > 17
 
 template<class _Iter>
 concept __can_use_postfix_proxy =
@@ -37,31 +37,18 @@ concept __can_use_postfix_proxy =
 template<input_or_output_iterator _Iter, sentinel_for<_Iter> _Sent>
   requires (!same_as<_Iter, _Sent> && copyable<_Iter>)
 class common_iterator {
-  class __proxy {
-    friend common_iterator;
-
-    iter_value_t<_Iter> __value;
-    // We can move __x because the only caller verifies that __x is not a reference.
-    constexpr explicit __proxy(iter_reference_t<_Iter>&& __x)
-      : __value(_VSTD::move(__x)) {}
-
-  public:
+  struct __proxy {
     constexpr const iter_value_t<_Iter>* operator->() const noexcept {
-      return _VSTD::addressof(__value);
+      return _VSTD::addressof(__value_);
     }
+    iter_value_t<_Iter> __value_;
   };
 
-  class __postfix_proxy {
-    friend common_iterator;
-
-    iter_value_t<_Iter> __value;
-    constexpr explicit __postfix_proxy(iter_reference_t<_Iter>&& __x)
-      : __value(_VSTD::forward<iter_reference_t<_Iter>>(__x)) {}
-
-  public:
+  struct __postfix_proxy {
     constexpr const iter_value_t<_Iter>& operator*() const noexcept {
-      return __value;
+      return __value_;
     }
+    iter_value_t<_Iter> __value_;
   };
 
 public:
@@ -133,7 +120,7 @@ public:
       auto&& __tmp = *_VSTD::__unchecked_get<_Iter>(__hold_);
       return _VSTD::addressof(__tmp);
     } else {
-      return __proxy(*_VSTD::__unchecked_get<_Iter>(__hold_));
+      return __proxy{*_VSTD::__unchecked_get<_Iter>(__hold_)};
     }
   }
 
@@ -152,7 +139,7 @@ public:
                          !__can_use_postfix_proxy<_Iter>) {
       return _VSTD::__unchecked_get<_Iter>(__hold_)++;
     } else {
-      __postfix_proxy __p(**this);
+      auto __p = __postfix_proxy{**this};
       ++*this;
       return __p;
     }
@@ -276,7 +263,7 @@ struct iterator_traits<common_iterator<_Iter, _Sent>> {
   using reference = iter_reference_t<_Iter>;
 };
 
-#endif // !defined(_LIBCPP_HAS_NO_CONCEPTS)
+#endif // _LIBCPP_STD_VER > 17
 
 _LIBCPP_END_NAMESPACE_STD
 
diff --git a/contrib/libs/cxxsupp/libcxx/include/__iterator/concepts.h b/contrib/libs/cxxsupp/libcxx/include/__iterator/concepts.h
index 92ef781457..bd68889333 100644
--- a/contrib/libs/cxxsupp/libcxx/include/__iterator/concepts.h
+++ b/contrib/libs/cxxsupp/libcxx/include/__iterator/concepts.h
@@ -26,7 +26,7 @@
 
 _LIBCPP_BEGIN_NAMESPACE_STD
 
-#if !defined(_LIBCPP_HAS_NO_CONCEPTS)
+#if _LIBCPP_STD_VER > 17
 
 // [iterator.concept.readable]
 template<class _In>
@@ -273,7 +273,7 @@ concept indirectly_copyable_storable =
 // Note: indirectly_swappable is located in iter_swap.h to prevent a dependency cycle
 // (both iter_swap and indirectly_swappable require indirectly_readable).
 
-#endif // !defined(_LIBCPP_HAS_NO_CONCEPTS)
+#endif // _LIBCPP_STD_VER > 17
 
 _LIBCPP_END_NAMESPACE_STD
 
diff --git a/contrib/libs/cxxsupp/libcxx/include/__iterator/counted_iterator.h b/contrib/libs/cxxsupp/libcxx/include/__iterator/counted_iterator.h
index 826d5de51f..b0f5c66ecf 100644
--- a/contrib/libs/cxxsupp/libcxx/include/__iterator/counted_iterator.h
+++ b/contrib/libs/cxxsupp/libcxx/include/__iterator/counted_iterator.h
@@ -30,7 +30,7 @@
 
 _LIBCPP_BEGIN_NAMESPACE_STD
 
-#if !defined(_LIBCPP_HAS_NO_CONCEPTS)
+#if _LIBCPP_STD_VER > 17
 
 template<class>
 struct __counted_iterator_concept {};
@@ -296,7 +296,7 @@ struct iterator_traits<counted_iterator<_Iter>> : iterator_traits<_Iter> {
                                 add_pointer_t<iter_reference_t<_Iter>>, void>;
 };
 
-#endif // !defined(_LIBCPP_HAS_NO_CONCEPTS)
+#endif // _LIBCPP_STD_VER > 17
 
 _LIBCPP_END_NAMESPACE_STD
 
diff --git a/contrib/libs/cxxsupp/libcxx/include/__iterator/distance.h b/contrib/libs/cxxsupp/libcxx/include/__iterator/distance.h
index 78b8177fae..8819078958 100644
--- a/contrib/libs/cxxsupp/libcxx/include/__iterator/distance.h
+++ b/contrib/libs/cxxsupp/libcxx/include/__iterator/distance.h
@@ -52,7 +52,7 @@ distance(_InputIter __first, _InputIter __last)
     return _VSTD::__distance(__first, __last, typename iterator_traits<_InputIter>::iterator_category());
 }
 
-#if !defined(_LIBCPP_HAS_NO_CONCEPTS) && !defined(_LIBCPP_HAS_NO_INCOMPLETE_RANGES)
+#if _LIBCPP_STD_VER > 17 && !defined(_LIBCPP_HAS_NO_INCOMPLETE_RANGES)
 
 // [range.iter.op.distance]
 
@@ -100,7 +100,7 @@ inline namespace __cpo {
 } // namespace __cpo
 } // namespace ranges
 
-#endif // !defined(_LIBCPP_HAS_NO_CONCEPTS) && !defined(_LIBCPP_HAS_NO_INCOMPLETE_RANGES)
+#endif // _LIBCPP_STD_VER > 17 && !defined(_LIBCPP_HAS_NO_INCOMPLETE_RANGES)
 
 _LIBCPP_END_NAMESPACE_STD
 
diff --git a/contrib/libs/cxxsupp/libcxx/include/__iterator/incrementable_traits.h b/contrib/libs/cxxsupp/libcxx/include/__iterator/incrementable_traits.h
index f36b417bf8..ef5f5110a3 100644
--- a/contrib/libs/cxxsupp/libcxx/include/__iterator/incrementable_traits.h
+++ b/contrib/libs/cxxsupp/libcxx/include/__iterator/incrementable_traits.h
@@ -20,7 +20,7 @@
 
 _LIBCPP_BEGIN_NAMESPACE_STD
 
-#if !defined(_LIBCPP_HAS_NO_CONCEPTS)
+#if _LIBCPP_STD_VER > 17
 
 // [incrementable.traits]
 template<class> struct incrementable_traits {};
@@ -65,7 +65,7 @@ using iter_difference_t = typename conditional_t<__is_primary_template<iterator_
                                                  incrementable_traits<remove_cvref_t<_Ip> >,
                                                  iterator_traits<remove_cvref_t<_Ip> > >::difference_type;
 
-#endif // !defined(_LIBCPP_HAS_NO_CONCEPTS)
+#endif // _LIBCPP_STD_VER > 17
 
 _LIBCPP_END_NAMESPACE_STD
 
diff --git a/contrib/libs/cxxsupp/libcxx/include/__iterator/indirectly_comparable.h b/contrib/libs/cxxsupp/libcxx/include/__iterator/indirectly_comparable.h
index 9002b21fd5..868190fc48 100644
--- a/contrib/libs/cxxsupp/libcxx/include/__iterator/indirectly_comparable.h
+++ b/contrib/libs/cxxsupp/libcxx/include/__iterator/indirectly_comparable.h
@@ -21,13 +21,13 @@
 
 _LIBCPP_BEGIN_NAMESPACE_STD
 
-#if !defined(_LIBCPP_HAS_NO_CONCEPTS)
+#if _LIBCPP_STD_VER > 17
 
 template <class _I1, class _I2, class _Rp, class _P1 = identity, class _P2 = identity>
 concept indirectly_comparable =
   indirect_binary_predicate<_Rp, projected<_I1, _P1>, projected<_I2, _P2>>;
 
-#endif // !defined(_LIBCPP_HAS_NO_CONCEPTS)
+#endif // _LIBCPP_STD_VER > 17
 
 _LIBCPP_END_NAMESPACE_STD
 
diff --git a/contrib/libs/cxxsupp/libcxx/include/__iterator/insert_iterator.h b/contrib/libs/cxxsupp/libcxx/include/__iterator/insert_iterator.h
index aba197ec21..8b313f2a85 100644
--- a/contrib/libs/cxxsupp/libcxx/include/__iterator/insert_iterator.h
+++ b/contrib/libs/cxxsupp/libcxx/include/__iterator/insert_iterator.h
@@ -24,7 +24,7 @@
 
 _LIBCPP_BEGIN_NAMESPACE_STD
 
-#if !defined(_LIBCPP_HAS_NO_CONCEPTS) && !defined(_LIBCPP_HAS_NO_INCOMPLETE_RANGES)
+#if _LIBCPP_STD_VER > 17 && !defined(_LIBCPP_HAS_NO_INCOMPLETE_RANGES)
 template <class _Container>
 using __insert_iterator_iter_t = ranges::iterator_t<_Container>;
 #else
diff --git a/contrib/libs/cxxsupp/libcxx/include/__iterator/iter_move.h b/contrib/libs/cxxsupp/libcxx/include/__iterator/iter_move.h
index 97d54c4a82..d8240ab9c2 100644
--- a/contrib/libs/cxxsupp/libcxx/include/__iterator/iter_move.h
+++ b/contrib/libs/cxxsupp/libcxx/include/__iterator/iter_move.h
@@ -23,7 +23,7 @@
 
 _LIBCPP_BEGIN_NAMESPACE_STD
 
-#if !defined(_LIBCPP_HAS_NO_CONCEPTS)
+#if _LIBCPP_STD_VER > 17
 
 // [iterator.cust.move]
 
@@ -39,6 +39,23 @@ concept __unqualified_iter_move =
     iter_move(std::forward<_Tp>(__t));
   };
 
+template<class _Tp>
+concept __move_deref =
+  !__unqualified_iter_move<_Tp> &&
+  requires (_Tp&& __t) {
+    *__t;
+    requires is_lvalue_reference_v<decltype(*__t)>;
+  };
+
+template<class _Tp>
+concept __just_deref =
+  !__unqualified_iter_move<_Tp> &&
+  !__move_deref<_Tp> &&
+  requires (_Tp&& __t) {
+    *__t;
+    requires (!is_lvalue_reference_v<decltype(*__t)>);
+  };
+
 // [iterator.cust.move]
 
 struct __fn {
@@ -51,17 +68,18 @@ struct __fn {
   }
 
   template<class _Ip>
-    requires (!__unqualified_iter_move<_Ip>) &&
-             requires { *declval<_Ip>(); }
-  [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr decltype(auto) operator()(_Ip&& __i) const
+    requires __move_deref<_Ip>
+  [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr auto operator()(_Ip&& __i) const
+    noexcept(noexcept(std::move(*std::forward<_Ip>(__i))))
+    -> decltype(      std::move(*std::forward<_Ip>(__i)))
+    { return          std::move(*std::forward<_Ip>(__i)); }
+
+  template<class _Ip>
+    requires __just_deref<_Ip>
+  [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr auto operator()(_Ip&& __i) const
     noexcept(noexcept(*std::forward<_Ip>(__i)))
-  {
-    if constexpr (is_lvalue_reference_v<decltype(*declval<_Ip>())>) {
-      return std::move(*std::forward<_Ip>(__i));
-    } else {
-      return *std::forward<_Ip>(__i);
-    }
-  }
+    -> decltype(      *std::forward<_Ip>(__i))
+    { return          *std::forward<_Ip>(__i); }
 };
 } // namespace __iter_move
 
@@ -74,7 +92,7 @@ template<__dereferenceable _Tp>
   requires requires(_Tp& __t) { { ranges::iter_move(__t) } -> __can_reference; }
 using iter_rvalue_reference_t = decltype(ranges::iter_move(declval<_Tp&>()));
 
-#endif // !defined(_LIBCPP_HAS_NO_CONCEPTS)
+#endif // _LIBCPP_STD_VER > 17
 
 _LIBCPP_END_NAMESPACE_STD
 
diff --git a/contrib/libs/cxxsupp/libcxx/include/__iterator/iter_swap.h b/contrib/libs/cxxsupp/libcxx/include/__iterator/iter_swap.h
index 291558fadc..9e06464c36 100644
--- a/contrib/libs/cxxsupp/libcxx/include/__iterator/iter_swap.h
+++ b/contrib/libs/cxxsupp/libcxx/include/__iterator/iter_swap.h
@@ -25,7 +25,7 @@
 
 _LIBCPP_BEGIN_NAMESPACE_STD
 
-#if !defined(_LIBCPP_HAS_NO_CONCEPTS)
+#if _LIBCPP_STD_VER > 17
 
 // [iter.cust.swap]
 
@@ -99,7 +99,7 @@ concept indirectly_swappable =
     ranges::iter_swap(__i2, __i1);
   };
 
-#endif // !defined(_LIBCPP_HAS_NO_CONCEPTS)
+#endif // _LIBCPP_STD_VER > 17
 
 _LIBCPP_END_NAMESPACE_STD
 
diff --git a/contrib/libs/cxxsupp/libcxx/include/__iterator/iterator_traits.h b/contrib/libs/cxxsupp/libcxx/include/__iterator/iterator_traits.h
index e7d25fc7df..775f227004 100644
--- a/contrib/libs/cxxsupp/libcxx/include/__iterator/iterator_traits.h
+++ b/contrib/libs/cxxsupp/libcxx/include/__iterator/iterator_traits.h
@@ -22,7 +22,7 @@
 
 _LIBCPP_BEGIN_NAMESPACE_STD
 
-#if !defined(_LIBCPP_HAS_NO_CONCEPTS)
+#if _LIBCPP_STD_VER > 17
 
 template <class _Tp>
 using __with_reference = _Tp&;
@@ -41,7 +41,7 @@ concept __dereferenceable = requires(_Tp& __t) {
 template<__dereferenceable _Tp>
 using iter_reference_t = decltype(*declval<_Tp&>());
 
-#endif // !defined(_LIBCPP_HAS_NO_CONCEPTS)
+#endif // _LIBCPP_STD_VER > 17
 
 template <class _Iter>
 struct _LIBCPP_TEMPLATE_VIS iterator_traits;
@@ -139,7 +139,7 @@ public:
     static const bool value = sizeof(__test<_Tp>(nullptr)) == 1;
 };
 
-#if !defined(_LIBCPP_HAS_NO_CONCEPTS)
+#if _LIBCPP_STD_VER > 17
 
 // The `cpp17-*-iterator` exposition-only concepts are easily confused with the Cpp17*Iterator tables,
 // so they've been banished to a namespace that makes it obvious they have a niche use-case.
@@ -362,7 +362,7 @@ struct iterator_traits : __iterator_traits<_Ip> {
   using __primary_template = iterator_traits;
 };
 
-#else // !defined(_LIBCPP_HAS_NO_CONCEPTS)
+#else // _LIBCPP_STD_VER > 17
 
 template <class _Iter, bool> struct __iterator_traits {};
 
@@ -399,10 +399,10 @@ struct _LIBCPP_TEMPLATE_VIS iterator_traits
 
   using __primary_template = iterator_traits;
 };
-#endif // !defined(_LIBCPP_HAS_NO_CONCEPTS)
+#endif // _LIBCPP_STD_VER > 17
 
 template<class _Tp>
-#if !defined(_LIBCPP_HAS_NO_CONCEPTS)
+#if _LIBCPP_STD_VER > 17
 requires is_object_v<_Tp>
 #endif
 struct _LIBCPP_TEMPLATE_VIS iterator_traits<_Tp*>
diff --git a/contrib/libs/cxxsupp/libcxx/include/__iterator/mergeable.h b/contrib/libs/cxxsupp/libcxx/include/__iterator/mergeable.h
index 13db6c7f0b..b9f2d081dc 100644
--- a/contrib/libs/cxxsupp/libcxx/include/__iterator/mergeable.h
+++ b/contrib/libs/cxxsupp/libcxx/include/__iterator/mergeable.h
@@ -22,7 +22,7 @@
 
 _LIBCPP_BEGIN_NAMESPACE_STD
 
-#if !defined(_LIBCPP_HAS_NO_CONCEPTS)
+#if _LIBCPP_STD_VER > 17
 
 template <class _Input1, class _Input2, class _Output,
           class _Comp = ranges::less, class _Proj1 = identity, class _Proj2 = identity>
@@ -34,7 +34,7 @@ concept mergeable =
     indirectly_copyable<_Input2, _Output> &&
     indirect_strict_weak_order<_Comp, projected<_Input1, _Proj1>, projected<_Input2, _Proj2>>;
 
-#endif // !defined(_LIBCPP_HAS_NO_CONCEPTS)
+#endif // _LIBCPP_STD_VER > 17
 
 _LIBCPP_END_NAMESPACE_STD
 
diff --git a/contrib/libs/cxxsupp/libcxx/include/__iterator/next.h b/contrib/libs/cxxsupp/libcxx/include/__iterator/next.h
index 2a37382cca..7939840b6d 100644
--- a/contrib/libs/cxxsupp/libcxx/include/__iterator/next.h
+++ b/contrib/libs/cxxsupp/libcxx/include/__iterator/next.h
@@ -35,7 +35,7 @@ inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14
   return __x;
 }
 
-#if !defined(_LIBCPP_HAS_NO_CONCEPTS) && !defined(_LIBCPP_HAS_NO_INCOMPLETE_RANGES)
+#if _LIBCPP_STD_VER > 17 && !defined(_LIBCPP_HAS_NO_INCOMPLETE_RANGES)
 
 // [range.iter.op.next]
 
@@ -79,7 +79,7 @@ inline namespace __cpo {
 } // namespace __cpo
 } // namespace ranges
 
-#endif // !defined(_LIBCPP_HAS_NO_CONCEPTS) && !defined(_LIBCPP_HAS_NO_INCOMPLETE_RANGES)
+#endif // _LIBCPP_STD_VER > 17 && !defined(_LIBCPP_HAS_NO_INCOMPLETE_RANGES)
 
 _LIBCPP_END_NAMESPACE_STD
 
diff --git a/contrib/libs/cxxsupp/libcxx/include/__iterator/permutable.h b/contrib/libs/cxxsupp/libcxx/include/__iterator/permutable.h
index 85834a23c8..28d193eaae 100644
--- a/contrib/libs/cxxsupp/libcxx/include/__iterator/permutable.h
+++ b/contrib/libs/cxxsupp/libcxx/include/__iterator/permutable.h
@@ -20,7 +20,7 @@
 
 _LIBCPP_BEGIN_NAMESPACE_STD
 
-#if !defined(_LIBCPP_HAS_NO_CONCEPTS)
+#if _LIBCPP_STD_VER > 17
 
 template <class _Iterator>
 concept permutable =
@@ -28,7 +28,7 @@ concept permutable =
     indirectly_movable_storable<_Iterator, _Iterator> &&
     indirectly_swappable<_Iterator, _Iterator>;
 
-#endif // !defined(_LIBCPP_HAS_NO_CONCEPTS)
+#endif // _LIBCPP_STD_VER > 17
 
 _LIBCPP_END_NAMESPACE_STD
 
diff --git a/contrib/libs/cxxsupp/libcxx/include/__iterator/prev.h b/contrib/libs/cxxsupp/libcxx/include/__iterator/prev.h
index 36bf3d906a..e68b8759b7 100644
--- a/contrib/libs/cxxsupp/libcxx/include/__iterator/prev.h
+++ b/contrib/libs/cxxsupp/libcxx/include/__iterator/prev.h
@@ -34,7 +34,7 @@ inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14
   return __x;
 }
 
-#if !defined(_LIBCPP_HAS_NO_CONCEPTS) && !defined(_LIBCPP_HAS_NO_INCOMPLETE_RANGES)
+#if _LIBCPP_STD_VER > 17 && !defined(_LIBCPP_HAS_NO_INCOMPLETE_RANGES)
 
 // [range.iter.op.prev]
 
@@ -71,7 +71,7 @@ inline namespace __cpo {
 } // namespace __cpo
 } // namespace ranges
 
-#endif // !defined(_LIBCPP_HAS_NO_CONCEPTS) && !defined(_LIBCPP_HAS_NO_INCOMPLETE_RANGES)
+#endif // _LIBCPP_STD_VER > 17 && !defined(_LIBCPP_HAS_NO_INCOMPLETE_RANGES)
 
 _LIBCPP_END_NAMESPACE_STD
 
diff --git a/contrib/libs/cxxsupp/libcxx/include/__iterator/projected.h b/contrib/libs/cxxsupp/libcxx/include/__iterator/projected.h
index 2edbe0da61..53526bd8e7 100644
--- a/contrib/libs/cxxsupp/libcxx/include/__iterator/projected.h
+++ b/contrib/libs/cxxsupp/libcxx/include/__iterator/projected.h
@@ -20,7 +20,7 @@
 
 _LIBCPP_BEGIN_NAMESPACE_STD
 
-#if !defined(_LIBCPP_HAS_NO_CONCEPTS)
+#if _LIBCPP_STD_VER > 17
 
 template<indirectly_readable _It, indirectly_regular_unary_invocable<_It> _Proj>
 struct projected {
@@ -33,7 +33,7 @@ struct incrementable_traits<projected<_It, _Proj>> {
   using difference_type = iter_difference_t<_It>;
 };
 
-#endif // !defined(_LIBCPP_HAS_NO_CONCEPTS)
+#endif // _LIBCPP_STD_VER > 17
 
 _LIBCPP_END_NAMESPACE_STD
 
diff --git a/contrib/libs/cxxsupp/libcxx/include/__iterator/readable_traits.h b/contrib/libs/cxxsupp/libcxx/include/__iterator/readable_traits.h
index 5bc59a89f3..500b46ac14 100644
--- a/contrib/libs/cxxsupp/libcxx/include/__iterator/readable_traits.h
+++ b/contrib/libs/cxxsupp/libcxx/include/__iterator/readable_traits.h
@@ -20,7 +20,7 @@
 
 _LIBCPP_BEGIN_NAMESPACE_STD
 
-#if !defined(_LIBCPP_HAS_NO_CONCEPTS)
+#if _LIBCPP_STD_VER > 17
 
 // [readable.traits]
 template<class> struct __cond_value_type {};
@@ -79,7 +79,7 @@ using iter_value_t = typename conditional_t<__is_primary_template<iterator_trait
                                             indirectly_readable_traits<remove_cvref_t<_Ip> >,
                                             iterator_traits<remove_cvref_t<_Ip> > >::value_type;
 
-#endif // !defined(_LIBCPP_HAS_NO_CONCEPTS)
+#endif // _LIBCPP_STD_VER > 17
 
 _LIBCPP_END_NAMESPACE_STD
 
diff --git a/contrib/libs/cxxsupp/libcxx/include/__iterator/reverse_iterator.h b/contrib/libs/cxxsupp/libcxx/include/__iterator/reverse_iterator.h
index 90bc2d752e..c77f461853 100644
--- a/contrib/libs/cxxsupp/libcxx/include/__iterator/reverse_iterator.h
+++ b/contrib/libs/cxxsupp/libcxx/include/__iterator/reverse_iterator.h
@@ -184,7 +184,7 @@ operator<=(const reverse_iterator<_Iter1>& __x, const reverse_iterator<_Iter2>&
     return __x.base() >= __y.base();
 }
 
-#if !defined(_LIBCPP_HAS_NO_CONCEPTS)
+#if _LIBCPP_STD_VER > 17
 template <class _Iter1, three_way_comparable_with<_Iter1> _Iter2>
 _LIBCPP_HIDE_FROM_ABI constexpr
 compare_three_way_result_t<_Iter1, _Iter2>
@@ -192,7 +192,7 @@ operator<=>(const reverse_iterator<_Iter1>& __x, const reverse_iterator<_Iter2>&
 {
     return __y.base() <=> __x.base();
 }
-#endif
+#endif // _LIBCPP_STD_VER > 17
 
 #ifndef _LIBCPP_CXX03_LANG
 template <class _Iter1, class _Iter2>
diff --git a/contrib/libs/cxxsupp/libcxx/include/__iterator/size.h b/contrib/libs/cxxsupp/libcxx/include/__iterator/size.h
index bf40207a86..e060134966 100644
--- a/contrib/libs/cxxsupp/libcxx/include/__iterator/size.h
+++ b/contrib/libs/cxxsupp/libcxx/include/__iterator/size.h
@@ -41,9 +41,14 @@ _NOEXCEPT_(noexcept(static_cast<common_type_t<ptrdiff_t, make_signed_t<decltype(
 ->                              common_type_t<ptrdiff_t, make_signed_t<decltype(__c.size())>>
 { return            static_cast<common_type_t<ptrdiff_t, make_signed_t<decltype(__c.size())>>>(__c.size()); }
 
+// GCC complains about the implicit conversion from ptrdiff_t to size_t in
+// the array bound.
+_LIBCPP_DIAGNOSTIC_PUSH
+_LIBCPP_GCC_DIAGNOSTIC_IGNORED("-Wsign-conversion")
 template <class _Tp, ptrdiff_t _Sz>
 _LIBCPP_INLINE_VISIBILITY
 constexpr ptrdiff_t ssize(const _Tp (&)[_Sz]) noexcept { return _Sz; }
+_LIBCPP_DIAGNOSTIC_POP
 #endif
 
 #endif // _LIBCPP_STD_VER > 14
diff --git a/contrib/libs/cxxsupp/libcxx/include/__iterator/sortable.h b/contrib/libs/cxxsupp/libcxx/include/__iterator/sortable.h
index 057e1549df..bcf934f87b 100644
--- a/contrib/libs/cxxsupp/libcxx/include/__iterator/sortable.h
+++ b/contrib/libs/cxxsupp/libcxx/include/__iterator/sortable.h
@@ -23,14 +23,14 @@
 
 _LIBCPP_BEGIN_NAMESPACE_STD
 
-#if !defined(_LIBCPP_HAS_NO_CONCEPTS)
+#if _LIBCPP_STD_VER > 17
 
 template <class _Iter, class _Comp = ranges::less, class _Proj = identity>
 concept sortable =
   permutable<_Iter> &&
   indirect_strict_weak_order<_Comp, projected<_Iter, _Proj>>;
 
-#endif // !defined(_LIBCPP_HAS_NO_CONCEPTS)
+#endif // _LIBCPP_STD_VER > 17
 
 _LIBCPP_END_NAMESPACE_STD
 
diff --git a/contrib/libs/cxxsupp/libcxx/include/__iterator/unreachable_sentinel.h b/contrib/libs/cxxsupp/libcxx/include/__iterator/unreachable_sentinel.h
index b94ca53f40..d77cc99f02 100644
--- a/contrib/libs/cxxsupp/libcxx/include/__iterator/unreachable_sentinel.h
+++ b/contrib/libs/cxxsupp/libcxx/include/__iterator/unreachable_sentinel.h
@@ -19,7 +19,7 @@
 
 _LIBCPP_BEGIN_NAMESPACE_STD
 
-#if !defined(_LIBCPP_HAS_NO_CONCEPTS)
+#if _LIBCPP_STD_VER > 17
 
 struct unreachable_sentinel_t {
   template<weakly_incrementable _Iter>
@@ -31,7 +31,7 @@ struct unreachable_sentinel_t {
 
 inline constexpr unreachable_sentinel_t unreachable_sentinel{};
 
-#endif // !defined(_LIBCPP_HAS_NO_CONCEPTS)
+#endif // _LIBCPP_STD_VER > 17
 
 _LIBCPP_END_NAMESPACE_STD