diff --git a/libcxx/include/__memory/raw_storage_iterator.h b/libcxx/include/__memory/raw_storage_iterator.h
--- a/libcxx/include/__memory/raw_storage_iterator.h
+++ b/libcxx/include/__memory/raw_storage_iterator.h
@@ -27,19 +27,31 @@
 
 template <class _OutputIterator, class _Tp>
 class _LIBCPP_TEMPLATE_VIS raw_storage_iterator
+#if _LIBCPP_STD_VER <= 14
     : public iterator<output_iterator_tag,
                       _Tp,                                         // purposefully not C++03
                       ptrdiff_t,                                   // purposefully not C++03
                       _Tp*,                                        // purposefully not C++03
                       raw_storage_iterator<_OutputIterator, _Tp>&> // purposefully not C++03
+#endif
 {
 private:
     _OutputIterator __x_;
 public:
-    _LIBCPP_INLINE_VISIBILITY explicit raw_storage_iterator(_OutputIterator __x) : __x_(__x) {}
-    _LIBCPP_INLINE_VISIBILITY raw_storage_iterator& operator*() {return *this;}
-    _LIBCPP_INLINE_VISIBILITY raw_storage_iterator& operator=(const _Tp& __element)
-        {::new ((void*)_VSTD::addressof(*__x_)) _Tp(__element); return *this;}
+#if _LIBCPP_STD_VER > 14
+  using iterator_category = output_iterator_tag;
+  using value_type = void;
+  using difference_type = void;
+  using pointer = void;
+  using reference = void;
+#endif
+
+  _LIBCPP_INLINE_VISIBILITY explicit raw_storage_iterator(_OutputIterator __x) : __x_(__x) {}
+  _LIBCPP_INLINE_VISIBILITY raw_storage_iterator& operator*() { return *this; }
+  _LIBCPP_INLINE_VISIBILITY raw_storage_iterator& operator=(const _Tp& __element) {
+    ::new ((void*)_VSTD::addressof(*__x_)) _Tp(__element);
+    return *this;
+  }
 #if _LIBCPP_STD_VER >= 14
     _LIBCPP_INLINE_VISIBILITY raw_storage_iterator& operator=(_Tp&& __element)
         {::new ((void*)_VSTD::addressof(*__x_)) _Tp(_VSTD::move(__element)); return *this;}
diff --git a/libcxx/include/iterator b/libcxx/include/iterator
--- a/libcxx/include/iterator
+++ b/libcxx/include/iterator
@@ -81,7 +81,8 @@
 
 template<class Category, class T, class Distance = ptrdiff_t,
          class Pointer = T*, class Reference = T&>
-struct iterator
+struct iterator                                            // until C++17
+struct [[deprecated)]] iterator                            // since C++17
 {
     typedef T         value_type;
     typedef Distance  difference_type;
@@ -483,7 +484,7 @@
 
 template<class _Category, class _Tp, class _Distance = ptrdiff_t,
          class _Pointer = _Tp*, class _Reference = _Tp&>
-struct _LIBCPP_TEMPLATE_VIS iterator
+struct _LIBCPP_TEMPLATE_VIS _LIBCPP_DEPRECATED_IN_CXX17 iterator
 {
     typedef _Tp        value_type;
     typedef _Distance  difference_type;
@@ -603,11 +604,13 @@
 
 template <class _Iter>
 class _LIBCPP_TEMPLATE_VIS reverse_iterator
+#if _LIBCPP_STD_VER <= 14
     : public iterator<typename iterator_traits<_Iter>::iterator_category,
                       typename iterator_traits<_Iter>::value_type,
                       typename iterator_traits<_Iter>::difference_type,
                       typename iterator_traits<_Iter>::pointer,
                       typename iterator_traits<_Iter>::reference>
+#endif
 {
 private:
     /*mutable*/ _Iter __t;  // no longer used as of LWG #2360, not removed due to ABI break
@@ -620,12 +623,15 @@
     _Iter current;
 public:
     typedef _Iter                                            iterator_type;
-    typedef typename iterator_traits<_Iter>::difference_type difference_type;
-    typedef typename iterator_traits<_Iter>::reference       reference;
-    typedef typename iterator_traits<_Iter>::pointer         pointer;
     typedef _If<__is_cpp17_random_access_iterator<_Iter>::value,
         random_access_iterator_tag,
         typename iterator_traits<_Iter>::iterator_category>  iterator_category;
+#if _LIBCPP_STD_VER > 14
+    typedef typename iterator_traits<_Iter>::value_type      value_type;
+#endif
+    typedef typename iterator_traits<_Iter>::difference_type difference_type;
+    typedef typename iterator_traits<_Iter>::pointer         pointer;
+    typedef typename iterator_traits<_Iter>::reference       reference;
 #if _LIBCPP_STD_VER > 17
     typedef _If<__is_cpp17_random_access_iterator<_Iter>::value,
         random_access_iterator_tag,
@@ -755,15 +761,24 @@
 
 template <class _Container>
 class _LIBCPP_TEMPLATE_VIS back_insert_iterator
+#if _LIBCPP_STD_VER <= 14
     : public iterator<output_iterator_tag,
                       void,
                       void,
                       void,
                       void>
+#endif
 {
 protected:
     _Container* container;
 public:
+#if _LIBCPP_STD_VER > 14
+    typedef output_iterator_tag iterator_category;
+    typedef void value_type;
+    typedef void difference_type;
+    typedef void pointer;
+    typedef void reference;
+#endif
     typedef _Container container_type;
 
     _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17 explicit back_insert_iterator(_Container& __x) : container(_VSTD::addressof(__x)) {}
@@ -788,15 +803,24 @@
 
 template <class _Container>
 class _LIBCPP_TEMPLATE_VIS front_insert_iterator
+#if _LIBCPP_STD_VER <= 14
     : public iterator<output_iterator_tag,
                       void,
                       void,
                       void,
                       void>
+#endif
 {
 protected:
     _Container* container;
 public:
+#if _LIBCPP_STD_VER > 14
+    typedef output_iterator_tag iterator_category;
+    typedef void value_type;
+    typedef void difference_type;
+    typedef void pointer;
+    typedef void reference;
+#endif
     typedef _Container container_type;
 
     _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17 explicit front_insert_iterator(_Container& __x) : container(_VSTD::addressof(__x)) {}
@@ -821,16 +845,25 @@
 
 template <class _Container>
 class _LIBCPP_TEMPLATE_VIS insert_iterator
+#if _LIBCPP_STD_VER <= 14
     : public iterator<output_iterator_tag,
                       void,
                       void,
                       void,
                       void>
+#endif
 {
 protected:
     _Container* container;
     typename _Container::iterator iter;
 public:
+#if _LIBCPP_STD_VER > 14
+    typedef output_iterator_tag iterator_category;
+    typedef void value_type;
+    typedef void difference_type;
+    typedef void pointer;
+    typedef void reference;
+#endif
     typedef _Container container_type;
 
     _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17 insert_iterator(_Container& __x, typename _Container::iterator __i)
@@ -857,9 +890,18 @@
 template <class _Tp, class _CharT = char,
           class _Traits = char_traits<_CharT>, class _Distance = ptrdiff_t>
 class _LIBCPP_TEMPLATE_VIS istream_iterator
+#if _LIBCPP_STD_VER <= 14
     : public iterator<input_iterator_tag, _Tp, _Distance, const _Tp*, const _Tp&>
+#endif
 {
 public:
+#if _LIBCPP_STD_VER > 14
+    typedef input_iterator_tag iterator_category;
+    typedef _Tp value_type;
+    typedef _Distance difference_type;
+    typedef const _Tp* pointer;
+    typedef const _Tp& reference;
+#endif
     typedef _CharT char_type;
     typedef _Traits traits_type;
     typedef basic_istream<_CharT,_Traits> istream_type;
@@ -918,7 +960,9 @@
 
 template <class _Tp, class _CharT = char, class _Traits = char_traits<_CharT> >
 class _LIBCPP_TEMPLATE_VIS ostream_iterator
+#if _LIBCPP_STD_VER <= 14
     : public iterator<output_iterator_tag, void, void, void, void>
+#endif
 {
 public:
     typedef output_iterator_tag             iterator_category;
@@ -957,11 +1001,20 @@
 
 template<class _CharT, class _Traits>
 class _LIBCPP_TEMPLATE_VIS istreambuf_iterator
+#if _LIBCPP_STD_VER <= 14
     : public iterator<input_iterator_tag, _CharT,
                       typename _Traits::off_type, _CharT*,
                       _CharT>
+#endif
 {
 public:
+#if _LIBCPP_STD_VER > 14
+    typedef input_iterator_tag              iterator_category;
+    typedef _CharT                          value_type;
+    typedef typename _Traits::off_type      difference_type;
+    typedef _CharT*                         pointer;
+    typedef _CharT                          reference;
+#endif
     typedef _CharT                          char_type;
     typedef _Traits                         traits_type;
     typedef typename _Traits::int_type      int_type;
@@ -1027,7 +1080,9 @@
 
 template <class _CharT, class _Traits>
 class _LIBCPP_TEMPLATE_VIS ostreambuf_iterator
+#if _LIBCPP_STD_VER <= 14
     : public iterator<output_iterator_tag, void, void, void, void>
+#endif
 {
 public:
     typedef output_iterator_tag                 iterator_category;
diff --git a/libcxx/test/libcxx/iterators/iterator.requirements/iterator.concepts/cpp20_iter_concepts.pass.cpp b/libcxx/test/libcxx/iterators/iterator.requirements/iterator.concepts/cpp20_iter_concepts.pass.cpp
--- a/libcxx/test/libcxx/iterators/iterator.requirements/iterator.concepts/cpp20_iter_concepts.pass.cpp
+++ b/libcxx/test/libcxx/iterators/iterator.requirements/iterator.concepts/cpp20_iter_concepts.pass.cpp
@@ -8,6 +8,9 @@
 
 // UNSUPPORTED: c++03
 
+#pragma clang diagnostic ignored "-Wdeprecated-declarations"
+#pragma GCC diagnostic ignored "-Wdeprecated-declarations"
+
 // ITER_TRAITS(I)
 
 // -- If the qualified-id ITER_TRAITS(I)::iterator_concept is valid and names a
@@ -24,20 +27,37 @@
 #include <iterator>
 struct OtherTag : std::input_iterator_tag {};
 struct OtherTagTwo : std::output_iterator_tag {};
-struct MyIter : std::iterator<std::random_access_iterator_tag, char> {
+
+struct MyIter {
+  using iterator_category = std::random_access_iterator_tag;
   using iterator_concept = int;
+  using value_type = char;
+  using difference_type = std::ptrdiff_t;
+  using pointer = char*;
+  using reference = char&;
 };
-struct MyIter2 : std::iterator<OtherTag, char> {
 
+struct MyIter2 {
+  using iterator_category = OtherTag;
+  using value_type = char;
+  using difference_type = std::ptrdiff_t;
+  using pointer = char*;
+  using reference = char&;
 };
+
 struct MyIter3 {};
 
 struct Empty {};
 struct EmptyWithSpecial {};
 namespace std {
 template <>
-struct iterator_traits<MyIter3>
-    : std::iterator<OtherTagTwo, char> {};
+struct iterator_traits<MyIter3> {
+  using iterator_category = OtherTagTwo;
+  using value_type = char;
+  using difference_type = std::ptrdiff_t;
+  using pointer = char*;
+  using reference = char&;
+};
 
 template <>
 struct iterator_traits<EmptyWithSpecial> {
diff --git a/libcxx/test/libcxx/iterators/iterator.requirements/iterator.concepts/cpp20_iter_traits.pass.cpp b/libcxx/test/libcxx/iterators/iterator.requirements/iterator.concepts/cpp20_iter_traits.pass.cpp
--- a/libcxx/test/libcxx/iterators/iterator.requirements/iterator.concepts/cpp20_iter_traits.pass.cpp
+++ b/libcxx/test/libcxx/iterators/iterator.requirements/iterator.concepts/cpp20_iter_traits.pass.cpp
@@ -18,17 +18,48 @@
 
 #include <iterator>
 
-struct MyIter : std::iterator<std::random_access_iterator_tag, char> {};
-struct MyIter2 : std::iterator<std::random_access_iterator_tag, char> {};
-struct MyIter3 : std::iterator<std::random_access_iterator_tag, char> {};
+struct MyIter {
+  using iterator_category = std::random_access_iterator_tag;
+  using value_type = char;
+  using difference_type = std::ptrdiff_t;
+  using pointer = char*;
+  using reference = char&;
+};
+
+struct MyIter2 {
+  using iterator_category = std::random_access_iterator_tag;
+  using value_type = char;
+  using difference_type = std::ptrdiff_t;
+  using pointer = char*;
+  using reference = char&;
+};
+
+struct MyIter3 {
+  using iterator_category = std::random_access_iterator_tag;
+  using value_type = char;
+  using difference_type = std::ptrdiff_t;
+  using pointer = char*;
+  using reference = char&;
+};
 
 namespace std {
 template <>
-struct iterator_traits<MyIter>
-    : iterator_traits<std::iterator<std::random_access_iterator_tag, char> > {};
+struct iterator_traits<MyIter> {
+  using iterator_category = std::random_access_iterator_tag;
+  using value_type = char;
+  using difference_type = std::ptrdiff_t;
+  using pointer = char*;
+  using reference = char&;
+};
+
 template <>
-struct iterator_traits<MyIter2>
-    : std::iterator<std::random_access_iterator_tag, char> {};
+struct iterator_traits<MyIter2> {
+  using iterator_category = std::random_access_iterator_tag;
+  using value_type = char;
+  using difference_type = std::ptrdiff_t;
+  using pointer = char*;
+  using reference = char&;
+};
 
 } // namespace std
 
diff --git a/libcxx/test/std/iterators/iterator.primitives/iterator.basic/deprecated.verify.cpp b/libcxx/test/std/iterators/iterator.primitives/iterator.basic/deprecated.verify.cpp
new file mode 100644
--- /dev/null
+++ b/libcxx/test/std/iterators/iterator.primitives/iterator.basic/deprecated.verify.cpp
@@ -0,0 +1,16 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+// UNSUPPORTED: c++03, c++11, c++14
+
+// std::iterator
+
+#include <iterator>
+
+std::iterator<std::input_iterator_tag, char> it;
+// expected-warning@-1{{'iterator<std::input_iterator_tag, char>' is deprecated}}
diff --git a/libcxx/test/std/iterators/iterator.primitives/iterator.basic/iterator.pass.cpp b/libcxx/test/std/iterators/iterator.primitives/iterator.basic/iterator.pass.cpp
--- a/libcxx/test/std/iterators/iterator.primitives/iterator.basic/iterator.pass.cpp
+++ b/libcxx/test/std/iterators/iterator.primitives/iterator.basic/iterator.pass.cpp
@@ -6,6 +6,9 @@
 //
 //===----------------------------------------------------------------------===//
 
+#pragma clang diagnostic ignored "-Wdeprecated-declarations"
+#pragma GCC diagnostic ignored "-Wdeprecated-declarations"
+
 // <iterator>
 
 // template<class Category, class T, class Distance = ptrdiff_t,
diff --git a/libcxx/test/std/iterators/predef.iterators/insert.iterators/back.insert.iterator/types.pass.cpp b/libcxx/test/std/iterators/predef.iterators/insert.iterators/back.insert.iterator/types.pass.cpp
--- a/libcxx/test/std/iterators/predef.iterators/insert.iterators/back.insert.iterator/types.pass.cpp
+++ b/libcxx/test/std/iterators/predef.iterators/insert.iterators/back.insert.iterator/types.pass.cpp
@@ -30,6 +30,9 @@
 
 #include "test_macros.h"
 
+#pragma clang diagnostic ignored "-Wdeprecated-declarations"
+#pragma GCC diagnostic ignored "-Wdeprecated-declarations"
+
 template <class C>
 struct find_container
     : private std::back_insert_iterator<C>
@@ -52,6 +55,13 @@
     static_assert((std::is_same<typename R::reference, void>::value), "");
     static_assert((std::is_same<typename R::pointer, void>::value), "");
     static_assert((std::is_same<typename R::iterator_category, std::output_iterator_tag>::value), "");
+
+    using iterator_base = std::iterator<std::output_iterator_tag, void, void, void, void>;
+#if TEST_STD_VER <= 14
+    static_assert(std::is_base_of<iterator_base, R>::value, "");
+#else
+    static_assert(!std::is_base_of_v<iterator_base, R>);
+#endif
 }
 
 int main(int, char**)
diff --git a/libcxx/test/std/iterators/predef.iterators/insert.iterators/front.insert.iterator/types.pass.cpp b/libcxx/test/std/iterators/predef.iterators/insert.iterators/front.insert.iterator/types.pass.cpp
--- a/libcxx/test/std/iterators/predef.iterators/insert.iterators/front.insert.iterator/types.pass.cpp
+++ b/libcxx/test/std/iterators/predef.iterators/insert.iterators/front.insert.iterator/types.pass.cpp
@@ -31,6 +31,9 @@
 
 #include "test_macros.h"
 
+#pragma clang diagnostic ignored "-Wdeprecated-declarations"
+#pragma GCC diagnostic ignored "-Wdeprecated-declarations"
+
 template <class C>
 struct find_container
     : private std::front_insert_iterator<C>
@@ -53,6 +56,13 @@
     static_assert((std::is_same<typename R::reference, void>::value), "");
     static_assert((std::is_same<typename R::pointer, void>::value), "");
     static_assert((std::is_same<typename R::iterator_category, std::output_iterator_tag>::value), "");
+
+    using iterator_base = std::iterator<std::output_iterator_tag, void, void, void, void>;
+#if TEST_STD_VER <= 14
+    static_assert(std::is_base_of<iterator_base, R>::value, "");
+#else
+    static_assert(!std::is_base_of_v<iterator_base, R>);
+#endif
 }
 
 int main(int, char**)
diff --git a/libcxx/test/std/iterators/predef.iterators/insert.iterators/insert.iterator/types.pass.cpp b/libcxx/test/std/iterators/predef.iterators/insert.iterators/insert.iterator/types.pass.cpp
--- a/libcxx/test/std/iterators/predef.iterators/insert.iterators/insert.iterator/types.pass.cpp
+++ b/libcxx/test/std/iterators/predef.iterators/insert.iterators/insert.iterator/types.pass.cpp
@@ -30,6 +30,9 @@
 #include <vector>
 #include "test_macros.h"
 
+#pragma clang diagnostic ignored "-Wdeprecated-declarations"
+#pragma GCC diagnostic ignored "-Wdeprecated-declarations"
+
 template <class C>
 struct find_members
     : private std::insert_iterator<C>
@@ -56,6 +59,13 @@
     static_assert((std::is_same<typename R::reference, void>::value), "");
     static_assert((std::is_same<typename R::pointer, void>::value), "");
     static_assert((std::is_same<typename R::iterator_category, std::output_iterator_tag>::value), "");
+
+    using iterator_base = std::iterator<std::output_iterator_tag, void, void, void, void>;
+#if TEST_STD_VER <= 14
+    static_assert(std::is_base_of<iterator_base, R>::value, "");
+#else
+    static_assert(!std::is_base_of_v<iterator_base, R>);
+#endif
 }
 
 int main(int, char**)
diff --git a/libcxx/test/std/iterators/predef.iterators/reverse.iterators/reverse.iterator/types.pass.cpp b/libcxx/test/std/iterators/predef.iterators/reverse.iterators/reverse.iterator/types.pass.cpp
--- a/libcxx/test/std/iterators/predef.iterators/reverse.iterators/reverse.iterator/types.pass.cpp
+++ b/libcxx/test/std/iterators/predef.iterators/reverse.iterators/reverse.iterator/types.pass.cpp
@@ -30,6 +30,9 @@
 #include "test_macros.h"
 #include "test_iterators.h"
 
+#pragma clang diagnostic ignored "-Wdeprecated-declarations"
+#pragma GCC diagnostic ignored "-Wdeprecated-declarations"
+
 template <class It>
 struct find_current
     : private std::reverse_iterator<It>
@@ -49,6 +52,13 @@
     static_assert((std::is_same<typename R::difference_type, typename T::difference_type>::value), "");
     static_assert((std::is_same<typename R::reference, typename T::reference>::value), "");
     static_assert((std::is_same<typename R::pointer, typename std::iterator_traits<It>::pointer>::value), "");
+
+    using iterator_base = std::iterator<typename T::iterator_category, char>;
+#if TEST_STD_VER <= 14
+    static_assert(std::is_base_of<iterator_base, R>::value, "");
+#else
+    static_assert(!std::is_base_of<iterator_base, R>::value);
+#endif
 #if TEST_STD_VER > 17
     if constexpr (std::is_same_v<typename T::iterator_category, std::contiguous_iterator_tag>) {
         static_assert((std::is_same<typename R::iterator_category, std::random_access_iterator_tag>::value), "");
diff --git a/libcxx/test/std/iterators/stream.iterators/istream.iterator/types.pass.cpp b/libcxx/test/std/iterators/stream.iterators/istream.iterator/types.pass.cpp
--- a/libcxx/test/std/iterators/stream.iterators/istream.iterator/types.pass.cpp
+++ b/libcxx/test/std/iterators/stream.iterators/istream.iterator/types.pass.cpp
@@ -38,14 +38,18 @@
 
 #include "test_macros.h"
 
+#pragma clang diagnostic ignored "-Wdeprecated-declarations"
+#pragma GCC diagnostic ignored "-Wdeprecated-declarations"
+
 int main(int, char**)
 {
     typedef std::istream_iterator<double> I1; // double is trivially destructible
+    using iterator_base = std::iterator<std::input_iterator_tag, double, std::ptrdiff_t, double const*, double const&>;
 #if TEST_STD_VER <= 14
-    static_assert((std::is_convertible<I1,
-        std::iterator<std::input_iterator_tag, double, std::ptrdiff_t,
-        const double*, const double&> >::value), "");
+    static_assert((std::is_convertible<I1, iterator_base>::value), "");
+    static_assert(std::is_base_of<iterator_base, std::istream_iterator<double> >::value, "");
 #else
+    static_assert(!std::is_base_of<iterator_base, std::istream_iterator<double> >::value, "");
     static_assert((std::is_same<I1::iterator_category, std::input_iterator_tag>::value), "");
     static_assert((std::is_same<I1::value_type, double>::value), "");
     static_assert((std::is_same<I1::difference_type, std::ptrdiff_t>::value), "");
diff --git a/libcxx/test/std/iterators/stream.iterators/istreambuf.iterator/types.pass.cpp b/libcxx/test/std/iterators/stream.iterators/istreambuf.iterator/types.pass.cpp
--- a/libcxx/test/std/iterators/stream.iterators/istreambuf.iterator/types.pass.cpp
+++ b/libcxx/test/std/iterators/stream.iterators/istreambuf.iterator/types.pass.cpp
@@ -31,9 +31,18 @@
 
 #include "test_macros.h"
 
+#pragma clang diagnostic ignored "-Wdeprecated-declarations"
+#pragma GCC diagnostic ignored "-Wdeprecated-declarations"
+
 int main(int, char**)
 {
     typedef std::istreambuf_iterator<char> I1;
+    using iterator_base = std::iterator<std::input_iterator_tag, char, std::char_traits<char>::off_type, char*, char>;
+#if TEST_STD_VER <= 14
+    static_assert(std::is_base_of<iterator_base, I1>::value, "");
+#else
+    static_assert(!std::is_base_of<iterator_base, I1>::value, "");
+#endif
     static_assert((std::is_same<I1::iterator_category, std::input_iterator_tag>::value), "");
     static_assert((std::is_same<I1::value_type, char>::value), "");
     static_assert((std::is_same<I1::difference_type, std::char_traits<char>::off_type>::value), "");
diff --git a/libcxx/test/std/iterators/stream.iterators/ostream.iterator/types.pass.cpp b/libcxx/test/std/iterators/stream.iterators/ostream.iterator/types.pass.cpp
--- a/libcxx/test/std/iterators/stream.iterators/ostream.iterator/types.pass.cpp
+++ b/libcxx/test/std/iterators/stream.iterators/ostream.iterator/types.pass.cpp
@@ -25,13 +25,18 @@
 
 #include "test_macros.h"
 
+#pragma clang diagnostic ignored "-Wdeprecated-declarations"
+#pragma GCC diagnostic ignored "-Wdeprecated-declarations"
+
 int main(int, char**)
 {
     typedef std::ostream_iterator<double> I1;
+    using iterator_base = std::iterator<std::output_iterator_tag, void, void, void, void>;
 #if TEST_STD_VER <= 14
-    static_assert((std::is_convertible<I1,
-        std::iterator<std::output_iterator_tag, void, void, void, void> >::value), "");
+    static_assert(std::is_base_of<iterator_base, I1>::value, "");
+    static_assert((std::is_convertible<I1, iterator_base>::value), "");
 #else
+    static_assert(!std::is_base_of<iterator_base, I1>::value, "");
     static_assert((std::is_same<I1::iterator_category, std::output_iterator_tag>::value), "");
     static_assert((std::is_same<I1::value_type, void>::value), "");
 #if TEST_STD_VER <= 17
diff --git a/libcxx/test/std/iterators/stream.iterators/ostreambuf.iterator/types.pass.cpp b/libcxx/test/std/iterators/stream.iterators/ostreambuf.iterator/types.pass.cpp
--- a/libcxx/test/std/iterators/stream.iterators/ostreambuf.iterator/types.pass.cpp
+++ b/libcxx/test/std/iterators/stream.iterators/ostreambuf.iterator/types.pass.cpp
@@ -26,13 +26,18 @@
 
 #include "test_macros.h"
 
+#pragma clang diagnostic ignored "-Wdeprecated-declarations"
+#pragma GCC diagnostic ignored "-Wdeprecated-declarations"
+
 int main(int, char**)
 {
     typedef std::ostreambuf_iterator<char> I1;
+    using iterator_base = std::iterator<std::output_iterator_tag, void, void, void, void>;
 #if TEST_STD_VER <= 14
-    static_assert((std::is_convertible<I1,
-        std::iterator<std::output_iterator_tag, void, void, void, void> >::value), "");
+    static_assert(std::is_base_of<iterator_base, I1>::value, "");
+    static_assert((std::is_convertible<I1, iterator_base>::value), "");
 #else
+    static_assert(!std::is_base_of<iterator_base, I1>::value, "");
     static_assert((std::is_same<I1::iterator_category, std::output_iterator_tag>::value), "");
     static_assert((std::is_same<I1::value_type, void>::value), "");
 #if TEST_STD_VER <= 17