[libc++] [P0887] Add newest feature-test macros; mark `type_identity` as implemented.

[• Quuxplusone]

Summary

__cpp_lib_type_identity was implemented way back in cf49ccd0 (Clang 8), probably before the feature-test macro had been settled on.

__cpp_lib_string_resize_and_overwrite will be added by D113013 so I didn't add it here.

Fixes https://llvm.org/PR47261

[philnik]

Could you remove __cpp_lib_string_resize_and_overwrite? It's already part of D113013 (and I plan to remove the constexpr test and land it once CI is available again). Otherwise LGTM!

[• Quuxplusone]

Removed __cpp_lib_string_resize_and_overwrite. Remembered to git add the new test file.

[Mordante]

LGTM, thanks for adding the other missing entries!

libcxx/utils/generate_feature_test_macro_components.py

74

Please update the patch title and description to match the changed scope.

[• Quuxplusone]

libcxx/utils/generate_feature_test_macro_components.py

74

The title is currently "[libc++] [P0887] Add newest feature-test macros; mark type_identity as implemented." What did you have in mind?

[Mordante]

libcxx/utils/generate_feature_test_macro_components.py

74

The title got me on the wrong foot due to the wording. It adds more macros than the one in P0887 and only marks P0887 as complete. So it seems a bit confusing, reading it again it's not really wrong. (Maybe just drop P0887 from the title.)

[• Quuxplusone]

poke CI

libcxx/docs/FeatureTestMacroTable.rst

.. table:: Current Status
     ``__cpp_lib_syncbuf``                             *unimplemented*
     ------------------------------------------------- -----------------
     ``__cpp_lib_three_way_comparison``                *unimplemented*
     ------------------------------------------------- -----------------
     ``__cpp_lib_to_address``                          ``201711L``
     ------------------------------------------------- -----------------
     ``__cpp_lib_to_array``                            ``201907L``
     ------------------------------------------------- -----------------
+    ``__cpp_lib_type_identity``                       ``201806L``
+    ------------------------------------------------- -----------------
     ``__cpp_lib_unwrap_ref``                          ``201811L``
     ------------------------------------------------- -----------------
     **C++ 2b**
     -------------------------------------------------------------------
+    ``__cpp_lib_allocate_at_least``                   *unimplemented*
+    ------------------------------------------------- -----------------
+    ``__cpp_lib_associative_heterogeneous_erasure``   *unimplemented*
+    ------------------------------------------------- -----------------
     ``__cpp_lib_byteswap``                            ``202110L``
     ------------------------------------------------- -----------------
+    ``__cpp_lib_constexpr_typeinfo``                  *unimplemented*
+    ------------------------------------------------- -----------------
+    ``__cpp_lib_invoke_r``                            *unimplemented*
+    ------------------------------------------------- -----------------
     ``__cpp_lib_is_scoped_enum``                      ``202011L``
     ------------------------------------------------- -----------------
     ``__cpp_lib_monadic_optional``                    ``202110L``
     ------------------------------------------------- -----------------
+    ``__cpp_lib_move_only_function``                  *unimplemented*
+    ------------------------------------------------- -----------------
+    ``__cpp_lib_out_ptr``                             *unimplemented*
+    ------------------------------------------------- -----------------
+    ``__cpp_lib_ranges_starts_ends_with``             *unimplemented*
+    ------------------------------------------------- -----------------
+    ``__cpp_lib_ranges_zip``                          *unimplemented*
+    ------------------------------------------------- -----------------
+    ``__cpp_lib_spanstream``                          *unimplemented*
+    ------------------------------------------------- -----------------
     ``__cpp_lib_stacktrace``                          *unimplemented*
     ------------------------------------------------- -----------------
     ``__cpp_lib_stdatomic_h``                         *unimplemented*
     ------------------------------------------------- -----------------
     ``__cpp_lib_string_contains``                     ``202011L``
     ------------------------------------------------- -----------------
     ``__cpp_lib_to_underlying``                       ``202102L``
     ================================================= =================
 

libcxx/include/version

 #ifndef _LIBCPP_VERSIONH
 #define _LIBCPP_VERSIONH
 
 /*
   version synopsis
 
 Macro name                                              Value   Headers
 __cpp_lib_addressof_constexpr                           201603L <memory>
+__cpp_lib_allocate_at_least                             202106L <memory>
 __cpp_lib_allocator_traits_is_always_equal              201411L <deque> <forward_list> <list>
                                                                 <map> <memory> <scoped_allocator>
                                                                 <set> <string> <unordered_map>
                                                                 <unordered_set> <vector>
 __cpp_lib_any                                           201606L <any>
 __cpp_lib_apply                                         201603L <tuple>
 __cpp_lib_array_constexpr                               201811L <array> <iterator>
                                                         201603L // C++17
 __cpp_lib_as_const                                      201510L <utility>
+__cpp_lib_associative_heterogeneous_erasure             202110L <map> <set> <unordered_map>
+                                                                <unordered_set>
 __cpp_lib_assume_aligned                                201811L <memory>
 __cpp_lib_atomic_flag_test                              201907L <atomic>
 __cpp_lib_atomic_float                                  201711L <atomic>
 __cpp_lib_atomic_is_always_lock_free                    201603L <atomic>
 __cpp_lib_atomic_lock_free_type_aliases                 201907L <atomic>
 __cpp_lib_atomic_ref                                    201806L <atomic>
 __cpp_lib_atomic_shared_ptr                             201711L <atomic>
 __cpp_lib_atomic_value_initialization                   201911L <atomic> <memory>

 __cpp_lib_constexpr_dynamic_alloc                       201907L <memory>
 __cpp_lib_constexpr_functional                          201907L <functional>
 __cpp_lib_constexpr_iterator                            201811L <iterator>
 __cpp_lib_constexpr_memory                              201811L <memory>
 __cpp_lib_constexpr_numeric                             201911L <numeric>
 __cpp_lib_constexpr_string                              201811L <string>
 __cpp_lib_constexpr_string_view                         201811L <string_view>
 __cpp_lib_constexpr_tuple                               201811L <tuple>
+__cpp_lib_constexpr_typeinfo                            202106L <typeinfo>
 __cpp_lib_constexpr_utility                             201811L <utility>
 __cpp_lib_constexpr_vector                              201907L <vector>
 __cpp_lib_coroutine                                     201902L <coroutine>
 __cpp_lib_destroying_delete                             201806L <new>
 __cpp_lib_enable_shared_from_this                       201603L <memory>
 __cpp_lib_endian                                        201907L <bit>
 __cpp_lib_erase_if                                      202002L <deque> <forward_list> <list>
                                                                 <map> <set> <string>

 __cpp_lib_hypot                                         201603L <cmath>
 __cpp_lib_incomplete_container_elements                 201505L <forward_list> <list> <vector>
 __cpp_lib_int_pow2                                      202002L <bit>
 __cpp_lib_integer_comparison_functions                  202002L <utility>
 __cpp_lib_integer_sequence                              201304L <utility>
 __cpp_lib_integral_constant_callable                    201304L <type_traits>
 __cpp_lib_interpolate                                   201902L <cmath> <numeric>
 __cpp_lib_invoke                                        201411L <functional>
+__cpp_lib_invoke_r                                      202106L <functional>
 __cpp_lib_is_aggregate                                  201703L <type_traits>
 __cpp_lib_is_constant_evaluated                         201811L <type_traits>
 __cpp_lib_is_final                                      201402L <type_traits>
 __cpp_lib_is_invocable                                  201703L <type_traits>
 __cpp_lib_is_layout_compatible                          201907L <type_traits>
 __cpp_lib_is_nothrow_convertible                        201806L <type_traits>
 __cpp_lib_is_null_pointer                               201309L <type_traits>
 __cpp_lib_is_pointer_interconvertible                   201907L <type_traits>
 __cpp_lib_is_scoped_enum                                202011L <type_traits>
 __cpp_lib_is_swappable                                  201603L <type_traits>
 __cpp_lib_jthread                                       201911L <stop_token> <thread>
 __cpp_lib_latch                                         201907L <latch>
 __cpp_lib_launder                                       201606L <new>
 __cpp_lib_list_remove_return_type                       201806L <forward_list> <list>
 __cpp_lib_logical_traits                                201510L <type_traits>
 __cpp_lib_make_from_tuple                               201606L <tuple>
 __cpp_lib_make_reverse_iterator                         201402L <iterator>
 __cpp_lib_make_unique                                   201304L <memory>
 __cpp_lib_map_try_emplace                               201411L <map>
 __cpp_lib_math_constants                                201907L <numbers>
 __cpp_lib_math_special_functions                        201603L <cmath>
 __cpp_lib_memory_resource                               201603L <memory_resource>
 __cpp_lib_monadic_optional                              202110L <optional>
+__cpp_lib_move_only_function                            202110L <functional>
 __cpp_lib_node_extract                                  201606L <map> <set> <unordered_map>
                                                                 <unordered_set>
 __cpp_lib_nonmember_container_access                    201411L <array> <deque> <forward_list>
                                                                 <iterator> <list> <map>
                                                                 <regex> <set> <string>
                                                                 <unordered_map> <unordered_set> <vector>
 __cpp_lib_not_fn                                        201603L <functional>
 __cpp_lib_null_iterators                                201304L <iterator>
 __cpp_lib_optional                                      201606L <optional>
+__cpp_lib_out_ptr                                       202106L <memory>
 __cpp_lib_parallel_algorithm                            201603L <algorithm> <numeric>
 __cpp_lib_polymorphic_allocator                         201902L <memory>
 __cpp_lib_quoted_string_io                              201304L <iomanip>
 __cpp_lib_ranges                                        201811L <algorithm> <functional> <iterator>
                                                                 <memory> <ranges>
+__cpp_lib_ranges_starts_ends_with                       202106L <algorithm>
+__cpp_lib_ranges_zip                                    202110L <ranges> <tuple> <utility>
 __cpp_lib_raw_memory_algorithms                         201606L <memory>
 __cpp_lib_remove_cvref                                  201711L <type_traits>
 __cpp_lib_result_of_sfinae                              201210L <functional> <type_traits>
 __cpp_lib_robust_nonmodifying_seq_ops                   201304L <algorithm>
 __cpp_lib_sample                                        201603L <algorithm>
 __cpp_lib_scoped_lock                                   201703L <mutex>
 __cpp_lib_semaphore                                     201907L <semaphore>
 __cpp_lib_shared_mutex                                  201505L <shared_mutex>
 __cpp_lib_shared_ptr_arrays                             201611L <memory>
 __cpp_lib_shared_ptr_weak_type                          201606L <memory>
 __cpp_lib_shared_timed_mutex                            201402L <shared_mutex>
 __cpp_lib_shift                                         201806L <algorithm>
 __cpp_lib_smart_ptr_for_overwrite                       202002L <memory>
 __cpp_lib_source_location                               201907L <source_location>
 __cpp_lib_span                                          202002L <span>
+__cpp_lib_spanstream                                    202106L <spanstream>
 __cpp_lib_ssize                                         201902L <iterator>
 __cpp_lib_stacktrace                                    202011L <stacktrace>
 __cpp_lib_starts_ends_with                              201711L <string> <string_view>
 __cpp_lib_stdatomic_h                                   202011L <stdatomic.h>
 __cpp_lib_string_contains                               202011L <string> <string_view>
 __cpp_lib_string_udls                                   201304L <string>
 __cpp_lib_string_view                                   201803L <string> <string_view>
                                                         201606L // C++17
 __cpp_lib_syncbuf                                       201803L <syncstream>
 __cpp_lib_three_way_comparison                          201907L <compare>
 __cpp_lib_to_address                                    201711L <memory>
 __cpp_lib_to_array                                      201907L <array>
 __cpp_lib_to_chars                                      201611L <charconv>
 __cpp_lib_to_underlying                                 202102L <utility>
 __cpp_lib_transformation_trait_aliases                  201304L <type_traits>
 __cpp_lib_transparent_operators                         201510L <functional> <memory>
                                                         201210L // C++14
 __cpp_lib_tuple_element_t                               201402L <tuple>
 __cpp_lib_tuples_by_type                                201304L <tuple> <utility>
+__cpp_lib_type_identity                                 201806L <type_traits>
 __cpp_lib_type_trait_variable_templates                 201510L <type_traits>
 __cpp_lib_uncaught_exceptions                           201411L <exception>
 __cpp_lib_unordered_map_try_emplace                     201411L <unordered_map>
 __cpp_lib_unwrap_ref                                    201811L <functional>
 __cpp_lib_variant                                       202102L <variant>
 __cpp_lib_void_t                                        201411L <type_traits>
 
 */

 # define __cpp_lib_ssize                                201902L
 # define __cpp_lib_starts_ends_with                     201711L
 # undef  __cpp_lib_string_view
 # define __cpp_lib_string_view                          201803L
 // # define __cpp_lib_syncbuf                              201803L
 // # define __cpp_lib_three_way_comparison                 201907L
 # define __cpp_lib_to_address                           201711L
 # define __cpp_lib_to_array                             201907L
+# define __cpp_lib_type_identity                        201806L
 # define __cpp_lib_unwrap_ref                           201811L
 #endif
 
 #if _LIBCPP_STD_VER > 20
+// # define __cpp_lib_allocate_at_least                    202106L
+// # define __cpp_lib_associative_heterogeneous_erasure    202110L
 # define __cpp_lib_byteswap                             202110L
+// # define __cpp_lib_constexpr_typeinfo                   202106L
+// # define __cpp_lib_invoke_r                             202106L
 # define __cpp_lib_is_scoped_enum                       202011L
 # define __cpp_lib_monadic_optional                     202110L
+// # define __cpp_lib_move_only_function                   202110L
+// # define __cpp_lib_out_ptr                              202106L
+// # define __cpp_lib_ranges_starts_ends_with              202106L
+// # define __cpp_lib_ranges_zip                           202110L
+// # define __cpp_lib_spanstream                           202106L
 // # define __cpp_lib_stacktrace                           202011L
 // # define __cpp_lib_stdatomic_h                          202011L
 # define __cpp_lib_string_contains                      202011L
 # define __cpp_lib_to_underlying                        202102L
 #endif
 
 // clang-format on
 
 #endif // _LIBCPP_VERSIONH

libcxx/test/std/language.support/support.limits/support.limits.general/algorithm.version.pass.cpp

 
 // Test the feature test macros defined by <algorithm>
 
 /*  Constant                                 Value
     __cpp_lib_clamp                          201603L [C++17]
     __cpp_lib_constexpr_algorithms           201806L [C++20]
     __cpp_lib_parallel_algorithm             201603L [C++17]
     __cpp_lib_ranges                         201811L [C++20]
+    __cpp_lib_ranges_starts_ends_with        202106L [C++2b]
     __cpp_lib_robust_nonmodifying_seq_ops    201304L [C++14]
     __cpp_lib_sample                         201603L [C++17]
     __cpp_lib_shift                          201806L [C++20]
 */
 
 #include <algorithm>
 #include "test_macros.h"
 

 # ifdef __cpp_lib_parallel_algorithm
 #   error "__cpp_lib_parallel_algorithm should not be defined before c++17"
 # endif
 
 # ifdef __cpp_lib_ranges
 #   error "__cpp_lib_ranges should not be defined before c++20"
 # endif
 
+# ifdef __cpp_lib_ranges_starts_ends_with
+#   error "__cpp_lib_ranges_starts_ends_with should not be defined before c++2b"
+# endif
+
 # ifdef __cpp_lib_robust_nonmodifying_seq_ops
 #   error "__cpp_lib_robust_nonmodifying_seq_ops should not be defined before c++14"
 # endif
 
 # ifdef __cpp_lib_sample
 #   error "__cpp_lib_sample should not be defined before c++17"
 # endif
 

 # ifdef __cpp_lib_parallel_algorithm
 #   error "__cpp_lib_parallel_algorithm should not be defined before c++17"
 # endif
 
 # ifdef __cpp_lib_ranges
 #   error "__cpp_lib_ranges should not be defined before c++20"
 # endif
 
+# ifdef __cpp_lib_ranges_starts_ends_with
+#   error "__cpp_lib_ranges_starts_ends_with should not be defined before c++2b"
+# endif
+
 # ifndef __cpp_lib_robust_nonmodifying_seq_ops
 #   error "__cpp_lib_robust_nonmodifying_seq_ops should be defined in c++14"
 # endif
 # if __cpp_lib_robust_nonmodifying_seq_ops != 201304L
 #   error "__cpp_lib_robust_nonmodifying_seq_ops should have the value 201304L in c++14"
 # endif
 
 # ifdef __cpp_lib_sample

 #     error "__cpp_lib_parallel_algorithm should not be defined because it is unimplemented in libc++!"
 #   endif
 # endif
 
 # ifdef __cpp_lib_ranges
 #   error "__cpp_lib_ranges should not be defined before c++20"
 # endif
 
+# ifdef __cpp_lib_ranges_starts_ends_with
+#   error "__cpp_lib_ranges_starts_ends_with should not be defined before c++2b"
+# endif
+
 # ifndef __cpp_lib_robust_nonmodifying_seq_ops
 #   error "__cpp_lib_robust_nonmodifying_seq_ops should be defined in c++17"
 # endif
 # if __cpp_lib_robust_nonmodifying_seq_ops != 201304L
 #   error "__cpp_lib_robust_nonmodifying_seq_ops should have the value 201304L in c++17"
 # endif
 
 # ifndef __cpp_lib_sample

 #     error "__cpp_lib_ranges should have the value 201811L in c++20"
 #   endif
 # else // _LIBCPP_VERSION
 #   ifdef __cpp_lib_ranges
 #     error "__cpp_lib_ranges should not be defined because it is unimplemented in libc++!"
 #   endif
 # endif
 
+# ifdef __cpp_lib_ranges_starts_ends_with
+#   error "__cpp_lib_ranges_starts_ends_with should not be defined before c++2b"
+# endif
+
 # ifndef __cpp_lib_robust_nonmodifying_seq_ops
 #   error "__cpp_lib_robust_nonmodifying_seq_ops should be defined in c++20"
 # endif
 # if __cpp_lib_robust_nonmodifying_seq_ops != 201304L
 #   error "__cpp_lib_robust_nonmodifying_seq_ops should have the value 201304L in c++20"
 # endif
 
 # ifndef __cpp_lib_sample

 #     error "__cpp_lib_ranges should have the value 201811L in c++2b"
 #   endif
 # else // _LIBCPP_VERSION
 #   ifdef __cpp_lib_ranges
 #     error "__cpp_lib_ranges should not be defined because it is unimplemented in libc++!"
 #   endif
 # endif
 
+# if !defined(_LIBCPP_VERSION)
+#   ifndef __cpp_lib_ranges_starts_ends_with
+#     error "__cpp_lib_ranges_starts_ends_with should be defined in c++2b"
+#   endif
+#   if __cpp_lib_ranges_starts_ends_with != 202106L
+#     error "__cpp_lib_ranges_starts_ends_with should have the value 202106L in c++2b"
+#   endif
+# else // _LIBCPP_VERSION
+#   ifdef __cpp_lib_ranges_starts_ends_with
+#     error "__cpp_lib_ranges_starts_ends_with should not be defined because it is unimplemented in libc++!"
+#   endif
+# endif
+
 # ifndef __cpp_lib_robust_nonmodifying_seq_ops
 #   error "__cpp_lib_robust_nonmodifying_seq_ops should be defined in c++2b"
 # endif
 # if __cpp_lib_robust_nonmodifying_seq_ops != 201304L
 #   error "__cpp_lib_robust_nonmodifying_seq_ops should have the value 201304L in c++2b"
 # endif
 
 # ifndef __cpp_lib_sample

libcxx/test/std/language.support/support.limits/support.limits.general/functional.version.pass.cpp

 
 // Test the feature test macros defined by <functional>
 
 /*  Constant                           Value
     __cpp_lib_bind_front               201907L [C++20]
     __cpp_lib_boyer_moore_searcher     201603L [C++17]
     __cpp_lib_constexpr_functional     201907L [C++20]
     __cpp_lib_invoke                   201411L [C++17]
+    __cpp_lib_invoke_r                 202106L [C++2b]
+    __cpp_lib_move_only_function       202110L [C++2b]
     __cpp_lib_not_fn                   201603L [C++17]
     __cpp_lib_ranges                   201811L [C++20]
     __cpp_lib_result_of_sfinae         201210L [C++14]
     __cpp_lib_transparent_operators    201210L [C++14]
                                        201510L [C++17]
     __cpp_lib_unwrap_ref               201811L [C++20]
 */
 

 # ifdef __cpp_lib_constexpr_functional
 #   error "__cpp_lib_constexpr_functional should not be defined before c++20"
 # endif
 
 # ifdef __cpp_lib_invoke
 #   error "__cpp_lib_invoke should not be defined before c++17"
 # endif
 
+# ifdef __cpp_lib_invoke_r
+#   error "__cpp_lib_invoke_r should not be defined before c++2b"
+# endif
+
+# ifdef __cpp_lib_move_only_function
+#   error "__cpp_lib_move_only_function should not be defined before c++2b"
+# endif
+
 # ifdef __cpp_lib_not_fn
 #   error "__cpp_lib_not_fn should not be defined before c++17"
 # endif
 
 # ifdef __cpp_lib_ranges
 #   error "__cpp_lib_ranges should not be defined before c++20"
 # endif
 

 # ifdef __cpp_lib_constexpr_functional
 #   error "__cpp_lib_constexpr_functional should not be defined before c++20"
 # endif
 
 # ifdef __cpp_lib_invoke
 #   error "__cpp_lib_invoke should not be defined before c++17"
 # endif
 
+# ifdef __cpp_lib_invoke_r
+#   error "__cpp_lib_invoke_r should not be defined before c++2b"
+# endif
+
+# ifdef __cpp_lib_move_only_function
+#   error "__cpp_lib_move_only_function should not be defined before c++2b"
+# endif
+
 # ifdef __cpp_lib_not_fn
 #   error "__cpp_lib_not_fn should not be defined before c++17"
 # endif
 
 # ifdef __cpp_lib_ranges
 #   error "__cpp_lib_ranges should not be defined before c++20"
 # endif
 

 
 # ifndef __cpp_lib_invoke
 #   error "__cpp_lib_invoke should be defined in c++17"
 # endif
 # if __cpp_lib_invoke != 201411L
 #   error "__cpp_lib_invoke should have the value 201411L in c++17"
 # endif
 
+# ifdef __cpp_lib_invoke_r
+#   error "__cpp_lib_invoke_r should not be defined before c++2b"
+# endif
+
+# ifdef __cpp_lib_move_only_function
+#   error "__cpp_lib_move_only_function should not be defined before c++2b"
+# endif
+
 # ifndef __cpp_lib_not_fn
 #   error "__cpp_lib_not_fn should be defined in c++17"
 # endif
 # if __cpp_lib_not_fn != 201603L
 #   error "__cpp_lib_not_fn should have the value 201603L in c++17"
 # endif
 
 # ifdef __cpp_lib_ranges

 
 # ifndef __cpp_lib_invoke
 #   error "__cpp_lib_invoke should be defined in c++20"
 # endif
 # if __cpp_lib_invoke != 201411L
 #   error "__cpp_lib_invoke should have the value 201411L in c++20"
 # endif
 
+# ifdef __cpp_lib_invoke_r
+#   error "__cpp_lib_invoke_r should not be defined before c++2b"
+# endif
+
+# ifdef __cpp_lib_move_only_function
+#   error "__cpp_lib_move_only_function should not be defined before c++2b"
+# endif
+
 # ifndef __cpp_lib_not_fn
 #   error "__cpp_lib_not_fn should be defined in c++20"
 # endif
 # if __cpp_lib_not_fn != 201603L
 #   error "__cpp_lib_not_fn should have the value 201603L in c++20"
 # endif
 
 # if !defined(_LIBCPP_VERSION)

 
 # ifndef __cpp_lib_invoke
 #   error "__cpp_lib_invoke should be defined in c++2b"
 # endif
 # if __cpp_lib_invoke != 201411L
 #   error "__cpp_lib_invoke should have the value 201411L in c++2b"
 # endif
 
+# if !defined(_LIBCPP_VERSION)
+#   ifndef __cpp_lib_invoke_r
+#     error "__cpp_lib_invoke_r should be defined in c++2b"
+#   endif
+#   if __cpp_lib_invoke_r != 202106L
+#     error "__cpp_lib_invoke_r should have the value 202106L in c++2b"
+#   endif
+# else // _LIBCPP_VERSION
+#   ifdef __cpp_lib_invoke_r
+#     error "__cpp_lib_invoke_r should not be defined because it is unimplemented in libc++!"
+#   endif
+# endif
+
+# if !defined(_LIBCPP_VERSION)
+#   ifndef __cpp_lib_move_only_function
+#     error "__cpp_lib_move_only_function should be defined in c++2b"
+#   endif
+#   if __cpp_lib_move_only_function != 202110L
+#     error "__cpp_lib_move_only_function should have the value 202110L in c++2b"
+#   endif
+# else // _LIBCPP_VERSION
+#   ifdef __cpp_lib_move_only_function
+#     error "__cpp_lib_move_only_function should not be defined because it is unimplemented in libc++!"
+#   endif
+# endif
+
 # ifndef __cpp_lib_not_fn
 #   error "__cpp_lib_not_fn should be defined in c++2b"
 # endif
 # if __cpp_lib_not_fn != 201603L
 #   error "__cpp_lib_not_fn should have the value 201603L in c++2b"
 # endif
 
 # if !defined(_LIBCPP_VERSION)

libcxx/test/std/language.support/support.limits/support.limits.general/map.version.pass.cpp

 // and should not be edited manually.
 //
 // clang-format off
 
 // <map>
 
 // Test the feature test macros defined by <map>
 
-/*  Constant                                      Value
-    __cpp_lib_allocator_traits_is_always_equal    201411L [C++17]
-    __cpp_lib_erase_if                            202002L [C++20]
-    __cpp_lib_generic_associative_lookup          201304L [C++14]
-    __cpp_lib_map_try_emplace                     201411L [C++17]
-    __cpp_lib_node_extract                        201606L [C++17]
-    __cpp_lib_nonmember_container_access          201411L [C++17]
+/*  Constant                                       Value
+    __cpp_lib_allocator_traits_is_always_equal     201411L [C++17]
+    __cpp_lib_associative_heterogeneous_erasure    202110L [C++2b]
+    __cpp_lib_erase_if                             202002L [C++20]
+    __cpp_lib_generic_associative_lookup           201304L [C++14]
+    __cpp_lib_map_try_emplace                      201411L [C++17]
+    __cpp_lib_node_extract                         201606L [C++17]
+    __cpp_lib_nonmember_container_access           201411L [C++17]
 */
 
 #include <map>
 #include "test_macros.h"
 
 #if TEST_STD_VER < 14
 
 # ifdef __cpp_lib_allocator_traits_is_always_equal
 #   error "__cpp_lib_allocator_traits_is_always_equal should not be defined before c++17"
 # endif
 
+# ifdef __cpp_lib_associative_heterogeneous_erasure
+#   error "__cpp_lib_associative_heterogeneous_erasure should not be defined before c++2b"
+# endif
+
 # ifdef __cpp_lib_erase_if
 #   error "__cpp_lib_erase_if should not be defined before c++20"
 # endif
 
 # ifdef __cpp_lib_generic_associative_lookup
 #   error "__cpp_lib_generic_associative_lookup should not be defined before c++14"
 # endif
 

 # endif
 
 #elif TEST_STD_VER == 14
 
 # ifdef __cpp_lib_allocator_traits_is_always_equal
 #   error "__cpp_lib_allocator_traits_is_always_equal should not be defined before c++17"
 # endif
 
+# ifdef __cpp_lib_associative_heterogeneous_erasure
+#   error "__cpp_lib_associative_heterogeneous_erasure should not be defined before c++2b"
+# endif
+
 # ifdef __cpp_lib_erase_if
 #   error "__cpp_lib_erase_if should not be defined before c++20"
 # endif
 
 # ifndef __cpp_lib_generic_associative_lookup
 #   error "__cpp_lib_generic_associative_lookup should be defined in c++14"
 # endif
 # if __cpp_lib_generic_associative_lookup != 201304L

 
 # ifndef __cpp_lib_allocator_traits_is_always_equal
 #   error "__cpp_lib_allocator_traits_is_always_equal should be defined in c++17"
 # endif
 # if __cpp_lib_allocator_traits_is_always_equal != 201411L
 #   error "__cpp_lib_allocator_traits_is_always_equal should have the value 201411L in c++17"
 # endif
 
+# ifdef __cpp_lib_associative_heterogeneous_erasure
+#   error "__cpp_lib_associative_heterogeneous_erasure should not be defined before c++2b"
+# endif
+
 # ifdef __cpp_lib_erase_if
 #   error "__cpp_lib_erase_if should not be defined before c++20"
 # endif
 
 # ifndef __cpp_lib_generic_associative_lookup
 #   error "__cpp_lib_generic_associative_lookup should be defined in c++17"
 # endif
 # if __cpp_lib_generic_associative_lookup != 201304L

 
 # ifndef __cpp_lib_allocator_traits_is_always_equal
 #   error "__cpp_lib_allocator_traits_is_always_equal should be defined in c++20"
 # endif
 # if __cpp_lib_allocator_traits_is_always_equal != 201411L
 #   error "__cpp_lib_allocator_traits_is_always_equal should have the value 201411L in c++20"
 # endif
 
+# ifdef __cpp_lib_associative_heterogeneous_erasure
+#   error "__cpp_lib_associative_heterogeneous_erasure should not be defined before c++2b"
+# endif
+
 # ifndef __cpp_lib_erase_if
 #   error "__cpp_lib_erase_if should be defined in c++20"
 # endif
 # if __cpp_lib_erase_if != 202002L
 #   error "__cpp_lib_erase_if should have the value 202002L in c++20"
 # endif
 
 # ifndef __cpp_lib_generic_associative_lookup

 
 # ifndef __cpp_lib_allocator_traits_is_always_equal
 #   error "__cpp_lib_allocator_traits_is_always_equal should be defined in c++2b"
 # endif
 # if __cpp_lib_allocator_traits_is_always_equal != 201411L
 #   error "__cpp_lib_allocator_traits_is_always_equal should have the value 201411L in c++2b"
 # endif
 
+# if !defined(_LIBCPP_VERSION)
+#   ifndef __cpp_lib_associative_heterogeneous_erasure
+#     error "__cpp_lib_associative_heterogeneous_erasure should be defined in c++2b"
+#   endif
+#   if __cpp_lib_associative_heterogeneous_erasure != 202110L
+#     error "__cpp_lib_associative_heterogeneous_erasure should have the value 202110L in c++2b"
+#   endif
+# else // _LIBCPP_VERSION
+#   ifdef __cpp_lib_associative_heterogeneous_erasure
+#     error "__cpp_lib_associative_heterogeneous_erasure should not be defined because it is unimplemented in libc++!"
+#   endif
+# endif
+
 # ifndef __cpp_lib_erase_if
 #   error "__cpp_lib_erase_if should be defined in c++2b"
 # endif
 # if __cpp_lib_erase_if != 202002L
 #   error "__cpp_lib_erase_if should have the value 202002L in c++2b"
 # endif
 
 # ifndef __cpp_lib_generic_associative_lookup

libcxx/test/std/language.support/support.limits/support.limits.general/memory.version.pass.cpp

 // clang-format off
 
 // <memory>
 
 // Test the feature test macros defined by <memory>
 
 /*  Constant                                      Value
     __cpp_lib_addressof_constexpr                 201603L [C++17]
+    __cpp_lib_allocate_at_least                   202106L [C++2b]
     __cpp_lib_allocator_traits_is_always_equal    201411L [C++17]
     __cpp_lib_assume_aligned                      201811L [C++20]
     __cpp_lib_atomic_value_initialization         201911L [C++20]
     __cpp_lib_constexpr_dynamic_alloc             201907L [C++20]
     __cpp_lib_constexpr_memory                    201811L [C++20]
     __cpp_lib_enable_shared_from_this             201603L [C++17]
     __cpp_lib_make_unique                         201304L [C++14]
+    __cpp_lib_out_ptr                             202106L [C++2b]
     __cpp_lib_polymorphic_allocator               201902L [C++20]
     __cpp_lib_ranges                              201811L [C++20]
     __cpp_lib_raw_memory_algorithms               201606L [C++17]
     __cpp_lib_shared_ptr_arrays                   201611L [C++17]
     __cpp_lib_shared_ptr_weak_type                201606L [C++17]
     __cpp_lib_smart_ptr_for_overwrite             202002L [C++20]
     __cpp_lib_to_address                          201711L [C++20]
     __cpp_lib_transparent_operators               201210L [C++14]
                                                   201510L [C++17]
 */
 
 #include <memory>
 #include "test_macros.h"
 
 #if TEST_STD_VER < 14
 
 # ifdef __cpp_lib_addressof_constexpr
 #   error "__cpp_lib_addressof_constexpr should not be defined before c++17"
 # endif
 
+# ifdef __cpp_lib_allocate_at_least
+#   error "__cpp_lib_allocate_at_least should not be defined before c++2b"
+# endif
+
 # ifdef __cpp_lib_allocator_traits_is_always_equal
 #   error "__cpp_lib_allocator_traits_is_always_equal should not be defined before c++17"
 # endif
 
 # ifdef __cpp_lib_assume_aligned
 #   error "__cpp_lib_assume_aligned should not be defined before c++20"
 # endif
 

 # ifdef __cpp_lib_enable_shared_from_this
 #   error "__cpp_lib_enable_shared_from_this should not be defined before c++17"
 # endif
 
 # ifdef __cpp_lib_make_unique
 #   error "__cpp_lib_make_unique should not be defined before c++14"
 # endif
 
+# ifdef __cpp_lib_out_ptr
+#   error "__cpp_lib_out_ptr should not be defined before c++2b"
+# endif
+
 # ifdef __cpp_lib_polymorphic_allocator
 #   error "__cpp_lib_polymorphic_allocator should not be defined before c++20"
 # endif
 
 # ifdef __cpp_lib_ranges
 #   error "__cpp_lib_ranges should not be defined before c++20"
 # endif
 

 # endif
 
 #elif TEST_STD_VER == 14
 
 # ifdef __cpp_lib_addressof_constexpr
 #   error "__cpp_lib_addressof_constexpr should not be defined before c++17"
 # endif
 
+# ifdef __cpp_lib_allocate_at_least
+#   error "__cpp_lib_allocate_at_least should not be defined before c++2b"
+# endif
+
 # ifdef __cpp_lib_allocator_traits_is_always_equal
 #   error "__cpp_lib_allocator_traits_is_always_equal should not be defined before c++17"
 # endif
 
 # ifdef __cpp_lib_assume_aligned
 #   error "__cpp_lib_assume_aligned should not be defined before c++20"
 # endif
 

 
 # ifndef __cpp_lib_make_unique
 #   error "__cpp_lib_make_unique should be defined in c++14"
 # endif
 # if __cpp_lib_make_unique != 201304L
 #   error "__cpp_lib_make_unique should have the value 201304L in c++14"
 # endif
 
+# ifdef __cpp_lib_out_ptr
+#   error "__cpp_lib_out_ptr should not be defined before c++2b"
+# endif
+
 # ifdef __cpp_lib_polymorphic_allocator
 #   error "__cpp_lib_polymorphic_allocator should not be defined before c++20"
 # endif
 
 # ifdef __cpp_lib_ranges
 #   error "__cpp_lib_ranges should not be defined before c++20"
 # endif
 

 
 # ifndef __cpp_lib_addressof_constexpr
 #   error "__cpp_lib_addressof_constexpr should be defined in c++17"
 # endif
 # if __cpp_lib_addressof_constexpr != 201603L
 #   error "__cpp_lib_addressof_constexpr should have the value 201603L in c++17"
 # endif
 
+# ifdef __cpp_lib_allocate_at_least
+#   error "__cpp_lib_allocate_at_least should not be defined before c++2b"
+# endif
+
 # ifndef __cpp_lib_allocator_traits_is_always_equal
 #   error "__cpp_lib_allocator_traits_is_always_equal should be defined in c++17"
 # endif
 # if __cpp_lib_allocator_traits_is_always_equal != 201411L
 #   error "__cpp_lib_allocator_traits_is_always_equal should have the value 201411L in c++17"
 # endif
 
 # ifdef __cpp_lib_assume_aligned

 
 # ifndef __cpp_lib_make_unique
 #   error "__cpp_lib_make_unique should be defined in c++17"
 # endif
 # if __cpp_lib_make_unique != 201304L
 #   error "__cpp_lib_make_unique should have the value 201304L in c++17"
 # endif
 
+# ifdef __cpp_lib_out_ptr
+#   error "__cpp_lib_out_ptr should not be defined before c++2b"
+# endif
+
 # ifdef __cpp_lib_polymorphic_allocator
 #   error "__cpp_lib_polymorphic_allocator should not be defined before c++20"
 # endif
 
 # ifdef __cpp_lib_ranges
 #   error "__cpp_lib_ranges should not be defined before c++20"
 # endif
 

 
 # ifndef __cpp_lib_addressof_constexpr
 #   error "__cpp_lib_addressof_constexpr should be defined in c++20"
 # endif
 # if __cpp_lib_addressof_constexpr != 201603L
 #   error "__cpp_lib_addressof_constexpr should have the value 201603L in c++20"
 # endif
 
+# ifdef __cpp_lib_allocate_at_least
+#   error "__cpp_lib_allocate_at_least should not be defined before c++2b"
+# endif
+
 # ifndef __cpp_lib_allocator_traits_is_always_equal
 #   error "__cpp_lib_allocator_traits_is_always_equal should be defined in c++20"
 # endif
 # if __cpp_lib_allocator_traits_is_always_equal != 201411L
 #   error "__cpp_lib_allocator_traits_is_always_equal should have the value 201411L in c++20"
 # endif
 
 # if !defined(_LIBCPP_VERSION)

 
 # ifndef __cpp_lib_make_unique
 #   error "__cpp_lib_make_unique should be defined in c++20"
 # endif
 # if __cpp_lib_make_unique != 201304L
 #   error "__cpp_lib_make_unique should have the value 201304L in c++20"
 # endif
 
+# ifdef __cpp_lib_out_ptr
+#   error "__cpp_lib_out_ptr should not be defined before c++2b"
+# endif
+
 # if !defined(_LIBCPP_VERSION)
 #   ifndef __cpp_lib_polymorphic_allocator
 #     error "__cpp_lib_polymorphic_allocator should be defined in c++20"
 #   endif
 #   if __cpp_lib_polymorphic_allocator != 201902L
 #     error "__cpp_lib_polymorphic_allocator should have the value 201902L in c++20"
 #   endif
 # else // _LIBCPP_VERSION

 
 # ifndef __cpp_lib_addressof_constexpr
 #   error "__cpp_lib_addressof_constexpr should be defined in c++2b"
 # endif
 # if __cpp_lib_addressof_constexpr != 201603L
 #   error "__cpp_lib_addressof_constexpr should have the value 201603L in c++2b"
 # endif
 
+# if !defined(_LIBCPP_VERSION)
+#   ifndef __cpp_lib_allocate_at_least
+#     error "__cpp_lib_allocate_at_least should be defined in c++2b"
+#   endif
+#   if __cpp_lib_allocate_at_least != 202106L
+#     error "__cpp_lib_allocate_at_least should have the value 202106L in c++2b"
+#   endif
+# else // _LIBCPP_VERSION
+#   ifdef __cpp_lib_allocate_at_least
+#     error "__cpp_lib_allocate_at_least should not be defined because it is unimplemented in libc++!"
+#   endif
+# endif
+
 # ifndef __cpp_lib_allocator_traits_is_always_equal
 #   error "__cpp_lib_allocator_traits_is_always_equal should be defined in c++2b"
 # endif
 # if __cpp_lib_allocator_traits_is_always_equal != 201411L
 #   error "__cpp_lib_allocator_traits_is_always_equal should have the value 201411L in c++2b"
 # endif
 
 # if !defined(_LIBCPP_VERSION)

 # ifndef __cpp_lib_make_unique
 #   error "__cpp_lib_make_unique should be defined in c++2b"
 # endif
 # if __cpp_lib_make_unique != 201304L
 #   error "__cpp_lib_make_unique should have the value 201304L in c++2b"
 # endif
 
 # if !defined(_LIBCPP_VERSION)
+#   ifndef __cpp_lib_out_ptr
+#     error "__cpp_lib_out_ptr should be defined in c++2b"
+#   endif
+#   if __cpp_lib_out_ptr != 202106L
+#     error "__cpp_lib_out_ptr should have the value 202106L in c++2b"
+#   endif
+# else // _LIBCPP_VERSION
+#   ifdef __cpp_lib_out_ptr
+#     error "__cpp_lib_out_ptr should not be defined because it is unimplemented in libc++!"
+#   endif
+# endif
+
+# if !defined(_LIBCPP_VERSION)
 #   ifndef __cpp_lib_polymorphic_allocator
 #     error "__cpp_lib_polymorphic_allocator should be defined in c++2b"
 #   endif
 #   if __cpp_lib_polymorphic_allocator != 201902L
 #     error "__cpp_lib_polymorphic_allocator should have the value 201902L in c++2b"
 #   endif
 # else // _LIBCPP_VERSION
 #   ifdef __cpp_lib_polymorphic_allocator

libcxx/test/std/language.support/support.limits/support.limits.general/ranges.version.pass.cpp

 // clang-format off
 
 // UNSUPPORTED: libcpp-has-no-incomplete-ranges
 
 // <ranges>
 
 // Test the feature test macros defined by <ranges>
 
-/*  Constant            Value
-    __cpp_lib_ranges    201811L [C++20]
+/*  Constant                Value
+    __cpp_lib_ranges        201811L [C++20]
+    __cpp_lib_ranges_zip    202110L [C++2b]
 */
 
 #include <ranges>
 #include "test_macros.h"
 
 #if TEST_STD_VER < 14
 
 # ifdef __cpp_lib_ranges
 #   error "__cpp_lib_ranges should not be defined before c++20"
 # endif
 
+# ifdef __cpp_lib_ranges_zip
+#   error "__cpp_lib_ranges_zip should not be defined before c++2b"
+# endif
+
 #elif TEST_STD_VER == 14
 
 # ifdef __cpp_lib_ranges
 #   error "__cpp_lib_ranges should not be defined before c++20"
 # endif
 
+# ifdef __cpp_lib_ranges_zip
+#   error "__cpp_lib_ranges_zip should not be defined before c++2b"
+# endif
+
 #elif TEST_STD_VER == 17
 
 # ifdef __cpp_lib_ranges
 #   error "__cpp_lib_ranges should not be defined before c++20"
 # endif
 
+# ifdef __cpp_lib_ranges_zip
+#   error "__cpp_lib_ranges_zip should not be defined before c++2b"
+# endif
+
 #elif TEST_STD_VER == 20
 
 # if !defined(_LIBCPP_VERSION)
 #   ifndef __cpp_lib_ranges
 #     error "__cpp_lib_ranges should be defined in c++20"
 #   endif
 #   if __cpp_lib_ranges != 201811L
 #     error "__cpp_lib_ranges should have the value 201811L in c++20"
 #   endif
 # else // _LIBCPP_VERSION
 #   ifdef __cpp_lib_ranges
 #     error "__cpp_lib_ranges should not be defined because it is unimplemented in libc++!"
 #   endif
 # endif
 
+# ifdef __cpp_lib_ranges_zip
+#   error "__cpp_lib_ranges_zip should not be defined before c++2b"
+# endif
+
 #elif TEST_STD_VER > 20
 
 # if !defined(_LIBCPP_VERSION)
 #   ifndef __cpp_lib_ranges
 #     error "__cpp_lib_ranges should be defined in c++2b"
 #   endif
 #   if __cpp_lib_ranges != 201811L
 #     error "__cpp_lib_ranges should have the value 201811L in c++2b"
 #   endif
 # else // _LIBCPP_VERSION
 #   ifdef __cpp_lib_ranges
 #     error "__cpp_lib_ranges should not be defined because it is unimplemented in libc++!"
 #   endif
 # endif
 
+# if !defined(_LIBCPP_VERSION)
+#   ifndef __cpp_lib_ranges_zip
+#     error "__cpp_lib_ranges_zip should be defined in c++2b"
+#   endif
+#   if __cpp_lib_ranges_zip != 202110L
+#     error "__cpp_lib_ranges_zip should have the value 202110L in c++2b"
+#   endif
+# else // _LIBCPP_VERSION
+#   ifdef __cpp_lib_ranges_zip
+#     error "__cpp_lib_ranges_zip should not be defined because it is unimplemented in libc++!"
+#   endif
+# endif
+
 #endif // TEST_STD_VER > 20
 
 int main(int, char**) { return 0; }

libcxx/test/std/language.support/support.limits/support.limits.general/set.version.pass.cpp

 // and should not be edited manually.
 //
 // clang-format off
 
 // <set>
 
 // Test the feature test macros defined by <set>
 
-/*  Constant                                      Value
-    __cpp_lib_allocator_traits_is_always_equal    201411L [C++17]
-    __cpp_lib_erase_if                            202002L [C++20]
-    __cpp_lib_generic_associative_lookup          201304L [C++14]
-    __cpp_lib_node_extract                        201606L [C++17]
-    __cpp_lib_nonmember_container_access          201411L [C++17]
+/*  Constant                                       Value
+    __cpp_lib_allocator_traits_is_always_equal     201411L [C++17]
+    __cpp_lib_associative_heterogeneous_erasure    202110L [C++2b]
+    __cpp_lib_erase_if                             202002L [C++20]
+    __cpp_lib_generic_associative_lookup           201304L [C++14]
+    __cpp_lib_node_extract                         201606L [C++17]
+    __cpp_lib_nonmember_container_access           201411L [C++17]
 */
 
 #include <set>
 #include "test_macros.h"
 
 #if TEST_STD_VER < 14
 
 # ifdef __cpp_lib_allocator_traits_is_always_equal
 #   error "__cpp_lib_allocator_traits_is_always_equal should not be defined before c++17"
 # endif
 
+# ifdef __cpp_lib_associative_heterogeneous_erasure
+#   error "__cpp_lib_associative_heterogeneous_erasure should not be defined before c++2b"
+# endif
+
 # ifdef __cpp_lib_erase_if
 #   error "__cpp_lib_erase_if should not be defined before c++20"
 # endif
 
 # ifdef __cpp_lib_generic_associative_lookup
 #   error "__cpp_lib_generic_associative_lookup should not be defined before c++14"
 # endif
 
 # ifdef __cpp_lib_node_extract
 #   error "__cpp_lib_node_extract should not be defined before c++17"
 # endif
 
 # ifdef __cpp_lib_nonmember_container_access
 #   error "__cpp_lib_nonmember_container_access should not be defined before c++17"
 # endif
 
 #elif TEST_STD_VER == 14
 
 # ifdef __cpp_lib_allocator_traits_is_always_equal
 #   error "__cpp_lib_allocator_traits_is_always_equal should not be defined before c++17"
 # endif
 
+# ifdef __cpp_lib_associative_heterogeneous_erasure
+#   error "__cpp_lib_associative_heterogeneous_erasure should not be defined before c++2b"
+# endif
+
 # ifdef __cpp_lib_erase_if
 #   error "__cpp_lib_erase_if should not be defined before c++20"
 # endif
 
 # ifndef __cpp_lib_generic_associative_lookup
 #   error "__cpp_lib_generic_associative_lookup should be defined in c++14"
 # endif
 # if __cpp_lib_generic_associative_lookup != 201304L

 
 # ifndef __cpp_lib_allocator_traits_is_always_equal
 #   error "__cpp_lib_allocator_traits_is_always_equal should be defined in c++17"
 # endif
 # if __cpp_lib_allocator_traits_is_always_equal != 201411L
 #   error "__cpp_lib_allocator_traits_is_always_equal should have the value 201411L in c++17"
 # endif
 
+# ifdef __cpp_lib_associative_heterogeneous_erasure
+#   error "__cpp_lib_associative_heterogeneous_erasure should not be defined before c++2b"
+# endif
+
 # ifdef __cpp_lib_erase_if
 #   error "__cpp_lib_erase_if should not be defined before c++20"
 # endif
 
 # ifndef __cpp_lib_generic_associative_lookup
 #   error "__cpp_lib_generic_associative_lookup should be defined in c++17"
 # endif
 # if __cpp_lib_generic_associative_lookup != 201304L

 
 # ifndef __cpp_lib_allocator_traits_is_always_equal
 #   error "__cpp_lib_allocator_traits_is_always_equal should be defined in c++20"
 # endif
 # if __cpp_lib_allocator_traits_is_always_equal != 201411L
 #   error "__cpp_lib_allocator_traits_is_always_equal should have the value 201411L in c++20"
 # endif
 
+# ifdef __cpp_lib_associative_heterogeneous_erasure
+#   error "__cpp_lib_associative_heterogeneous_erasure should not be defined before c++2b"
+# endif
+
 # ifndef __cpp_lib_erase_if
 #   error "__cpp_lib_erase_if should be defined in c++20"
 # endif
 # if __cpp_lib_erase_if != 202002L
 #   error "__cpp_lib_erase_if should have the value 202002L in c++20"
 # endif
 
 # ifndef __cpp_lib_generic_associative_lookup

 
 # ifndef __cpp_lib_allocator_traits_is_always_equal
 #   error "__cpp_lib_allocator_traits_is_always_equal should be defined in c++2b"
 # endif
 # if __cpp_lib_allocator_traits_is_always_equal != 201411L
 #   error "__cpp_lib_allocator_traits_is_always_equal should have the value 201411L in c++2b"
 # endif
 
+# if !defined(_LIBCPP_VERSION)
+#   ifndef __cpp_lib_associative_heterogeneous_erasure
+#     error "__cpp_lib_associative_heterogeneous_erasure should be defined in c++2b"
+#   endif
+#   if __cpp_lib_associative_heterogeneous_erasure != 202110L
+#     error "__cpp_lib_associative_heterogeneous_erasure should have the value 202110L in c++2b"
+#   endif
+# else // _LIBCPP_VERSION
+#   ifdef __cpp_lib_associative_heterogeneous_erasure
+#     error "__cpp_lib_associative_heterogeneous_erasure should not be defined because it is unimplemented in libc++!"
+#   endif
+# endif
+
 # ifndef __cpp_lib_erase_if
 #   error "__cpp_lib_erase_if should be defined in c++2b"
 # endif
 # if __cpp_lib_erase_if != 202002L
 #   error "__cpp_lib_erase_if should have the value 202002L in c++2b"
 # endif
 
 # ifndef __cpp_lib_generic_associative_lookup

libcxx/test/std/language.support/support.limits/support.limits.general/tuple.version.pass.cpp

 // <tuple>
 
 // Test the feature test macros defined by <tuple>
 
 /*  Constant                     Value
     __cpp_lib_apply              201603L [C++17]
     __cpp_lib_constexpr_tuple    201811L [C++20]
     __cpp_lib_make_from_tuple    201606L [C++17]
+    __cpp_lib_ranges_zip         202110L [C++2b]
     __cpp_lib_tuple_element_t    201402L [C++14]
     __cpp_lib_tuples_by_type     201304L [C++14]
 */
 
 #include <tuple>
 #include "test_macros.h"
 
 #if TEST_STD_VER < 14
 
 # ifdef __cpp_lib_apply
 #   error "__cpp_lib_apply should not be defined before c++17"
 # endif
 
 # ifdef __cpp_lib_constexpr_tuple
 #   error "__cpp_lib_constexpr_tuple should not be defined before c++20"
 # endif
 
 # ifdef __cpp_lib_make_from_tuple
 #   error "__cpp_lib_make_from_tuple should not be defined before c++17"
 # endif
 
+# ifdef __cpp_lib_ranges_zip
+#   error "__cpp_lib_ranges_zip should not be defined before c++2b"
+# endif
+
 # ifdef __cpp_lib_tuple_element_t
 #   error "__cpp_lib_tuple_element_t should not be defined before c++14"
 # endif
 
 # ifdef __cpp_lib_tuples_by_type
 #   error "__cpp_lib_tuples_by_type should not be defined before c++14"
 # endif
 
 #elif TEST_STD_VER == 14
 
 # ifdef __cpp_lib_apply
 #   error "__cpp_lib_apply should not be defined before c++17"
 # endif
 
 # ifdef __cpp_lib_constexpr_tuple
 #   error "__cpp_lib_constexpr_tuple should not be defined before c++20"
 # endif
 
 # ifdef __cpp_lib_make_from_tuple
 #   error "__cpp_lib_make_from_tuple should not be defined before c++17"
 # endif
 
+# ifdef __cpp_lib_ranges_zip
+#   error "__cpp_lib_ranges_zip should not be defined before c++2b"
+# endif
+
 # ifndef __cpp_lib_tuple_element_t
 #   error "__cpp_lib_tuple_element_t should be defined in c++14"
 # endif
 # if __cpp_lib_tuple_element_t != 201402L
 #   error "__cpp_lib_tuple_element_t should have the value 201402L in c++14"
 # endif
 
 # ifndef __cpp_lib_tuples_by_type

 
 # ifndef __cpp_lib_make_from_tuple
 #   error "__cpp_lib_make_from_tuple should be defined in c++17"
 # endif
 # if __cpp_lib_make_from_tuple != 201606L
 #   error "__cpp_lib_make_from_tuple should have the value 201606L in c++17"
 # endif
 
+# ifdef __cpp_lib_ranges_zip
+#   error "__cpp_lib_ranges_zip should not be defined before c++2b"
+# endif
+
 # ifndef __cpp_lib_tuple_element_t
 #   error "__cpp_lib_tuple_element_t should be defined in c++17"
 # endif
 # if __cpp_lib_tuple_element_t != 201402L
 #   error "__cpp_lib_tuple_element_t should have the value 201402L in c++17"
 # endif
 
 # ifndef __cpp_lib_tuples_by_type

 
 # ifndef __cpp_lib_make_from_tuple
 #   error "__cpp_lib_make_from_tuple should be defined in c++20"
 # endif
 # if __cpp_lib_make_from_tuple != 201606L
 #   error "__cpp_lib_make_from_tuple should have the value 201606L in c++20"
 # endif
 
+# ifdef __cpp_lib_ranges_zip
+#   error "__cpp_lib_ranges_zip should not be defined before c++2b"
+# endif
+
 # ifndef __cpp_lib_tuple_element_t
 #   error "__cpp_lib_tuple_element_t should be defined in c++20"
 # endif
 # if __cpp_lib_tuple_element_t != 201402L
 #   error "__cpp_lib_tuple_element_t should have the value 201402L in c++20"
 # endif
 
 # ifndef __cpp_lib_tuples_by_type

 
 # ifndef __cpp_lib_make_from_tuple
 #   error "__cpp_lib_make_from_tuple should be defined in c++2b"
 # endif
 # if __cpp_lib_make_from_tuple != 201606L
 #   error "__cpp_lib_make_from_tuple should have the value 201606L in c++2b"
 # endif
 
+# if !defined(_LIBCPP_VERSION)
+#   ifndef __cpp_lib_ranges_zip
+#     error "__cpp_lib_ranges_zip should be defined in c++2b"
+#   endif
+#   if __cpp_lib_ranges_zip != 202110L
+#     error "__cpp_lib_ranges_zip should have the value 202110L in c++2b"
+#   endif
+# else // _LIBCPP_VERSION
+#   ifdef __cpp_lib_ranges_zip
+#     error "__cpp_lib_ranges_zip should not be defined because it is unimplemented in libc++!"
+#   endif
+# endif
+
 # ifndef __cpp_lib_tuple_element_t
 #   error "__cpp_lib_tuple_element_t should be defined in c++2b"
 # endif
 # if __cpp_lib_tuple_element_t != 201402L
 #   error "__cpp_lib_tuple_element_t should have the value 201402L in c++2b"
 # endif
 
 # ifndef __cpp_lib_tuples_by_type

libcxx/test/std/language.support/support.limits/support.limits.general/type_traits.version.pass.cpp

/*  Constant                                       Value
     __cpp_lib_is_null_pointer                      201309L [C++14]
     __cpp_lib_is_pointer_interconvertible          201907L [C++20]
     __cpp_lib_is_scoped_enum                       202011L [C++2b]
     __cpp_lib_is_swappable                         201603L [C++17]
     __cpp_lib_logical_traits                       201510L [C++17]
     __cpp_lib_remove_cvref                         201711L [C++20]
     __cpp_lib_result_of_sfinae                     201210L [C++14]
     __cpp_lib_transformation_trait_aliases         201304L [C++14]
+    __cpp_lib_type_identity                        201806L [C++20]
     __cpp_lib_type_trait_variable_templates        201510L [C++17]
     __cpp_lib_void_t                               201411L [C++17]
 */
 
 #include <type_traits>
 #include "test_macros.h"
 
 #if TEST_STD_VER < 14

 # ifdef __cpp_lib_result_of_sfinae
 #   error "__cpp_lib_result_of_sfinae should not be defined before c++14"
 # endif
 
 # ifdef __cpp_lib_transformation_trait_aliases
 #   error "__cpp_lib_transformation_trait_aliases should not be defined before c++14"
 # endif
 
+# ifdef __cpp_lib_type_identity
+#   error "__cpp_lib_type_identity should not be defined before c++20"
+# endif
+
 # ifdef __cpp_lib_type_trait_variable_templates
 #   error "__cpp_lib_type_trait_variable_templates should not be defined before c++17"
 # endif
 
 # ifdef __cpp_lib_void_t
 #   error "__cpp_lib_void_t should not be defined before c++17"
 # endif
 

 
 # ifndef __cpp_lib_transformation_trait_aliases
 #   error "__cpp_lib_transformation_trait_aliases should be defined in c++14"
 # endif
 # if __cpp_lib_transformation_trait_aliases != 201304L
 #   error "__cpp_lib_transformation_trait_aliases should have the value 201304L in c++14"
 # endif
 
+# ifdef __cpp_lib_type_identity
+#   error "__cpp_lib_type_identity should not be defined before c++20"
+# endif
+
 # ifdef __cpp_lib_type_trait_variable_templates
 #   error "__cpp_lib_type_trait_variable_templates should not be defined before c++17"
 # endif
 
 # ifdef __cpp_lib_void_t
 #   error "__cpp_lib_void_t should not be defined before c++17"
 # endif
 

 
 # ifndef __cpp_lib_transformation_trait_aliases
 #   error "__cpp_lib_transformation_trait_aliases should be defined in c++17"
 # endif
 # if __cpp_lib_transformation_trait_aliases != 201304L
 #   error "__cpp_lib_transformation_trait_aliases should have the value 201304L in c++17"
 # endif
 
+# ifdef __cpp_lib_type_identity
+#   error "__cpp_lib_type_identity should not be defined before c++20"
+# endif
+
 # ifndef __cpp_lib_type_trait_variable_templates
 #   error "__cpp_lib_type_trait_variable_templates should be defined in c++17"
 # endif
 # if __cpp_lib_type_trait_variable_templates != 201510L
 #   error "__cpp_lib_type_trait_variable_templates should have the value 201510L in c++17"
 # endif
 
 # ifndef __cpp_lib_void_t

 
 # ifndef __cpp_lib_transformation_trait_aliases
 #   error "__cpp_lib_transformation_trait_aliases should be defined in c++20"
 # endif
 # if __cpp_lib_transformation_trait_aliases != 201304L
 #   error "__cpp_lib_transformation_trait_aliases should have the value 201304L in c++20"
 # endif
 
+# ifndef __cpp_lib_type_identity
+#   error "__cpp_lib_type_identity should be defined in c++20"
+# endif
+# if __cpp_lib_type_identity != 201806L
+#   error "__cpp_lib_type_identity should have the value 201806L in c++20"
+# endif
+
 # ifndef __cpp_lib_type_trait_variable_templates
 #   error "__cpp_lib_type_trait_variable_templates should be defined in c++20"
 # endif
 # if __cpp_lib_type_trait_variable_templates != 201510L
 #   error "__cpp_lib_type_trait_variable_templates should have the value 201510L in c++20"
 # endif
 
 # ifndef __cpp_lib_void_t

 
 # ifndef __cpp_lib_transformation_trait_aliases
 #   error "__cpp_lib_transformation_trait_aliases should be defined in c++2b"
 # endif
 # if __cpp_lib_transformation_trait_aliases != 201304L
 #   error "__cpp_lib_transformation_trait_aliases should have the value 201304L in c++2b"
 # endif
 
+# ifndef __cpp_lib_type_identity
+#   error "__cpp_lib_type_identity should be defined in c++2b"
+# endif
+# if __cpp_lib_type_identity != 201806L
+#   error "__cpp_lib_type_identity should have the value 201806L in c++2b"
+# endif
+
 # ifndef __cpp_lib_type_trait_variable_templates
 #   error "__cpp_lib_type_trait_variable_templates should be defined in c++2b"
 # endif
 # if __cpp_lib_type_trait_variable_templates != 201510L
 #   error "__cpp_lib_type_trait_variable_templates should have the value 201510L in c++2b"
 # endif
 
 # ifndef __cpp_lib_void_t

libcxx/test/std/language.support/support.limits/support.limits.general/typeinfo.version.pass.cpp

+//===----------------------------------------------------------------------===//
+//
+// 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
+//
+//===----------------------------------------------------------------------===//
+//
+// WARNING: This test was generated by generate_feature_test_macro_components.py
+// and should not be edited manually.
+//
+// clang-format off
+
+// <typeinfo>
+
+// Test the feature test macros defined by <typeinfo>
+
+/*  Constant                        Value
+    __cpp_lib_constexpr_typeinfo    202106L [C++2b]
+*/
+
+#include <typeinfo>
+#include "test_macros.h"
+
+#if TEST_STD_VER < 14
+
+# ifdef __cpp_lib_constexpr_typeinfo
+#   error "__cpp_lib_constexpr_typeinfo should not be defined before c++2b"
+# endif
+
+#elif TEST_STD_VER == 14
+
+# ifdef __cpp_lib_constexpr_typeinfo
+#   error "__cpp_lib_constexpr_typeinfo should not be defined before c++2b"
+# endif
+
+#elif TEST_STD_VER == 17
+
+# ifdef __cpp_lib_constexpr_typeinfo
+#   error "__cpp_lib_constexpr_typeinfo should not be defined before c++2b"
+# endif
+
+#elif TEST_STD_VER == 20
+
+# ifdef __cpp_lib_constexpr_typeinfo
+#   error "__cpp_lib_constexpr_typeinfo should not be defined before c++2b"
+# endif
+
+#elif TEST_STD_VER > 20
+
+# if !defined(_LIBCPP_VERSION)
+#   ifndef __cpp_lib_constexpr_typeinfo
+#     error "__cpp_lib_constexpr_typeinfo should be defined in c++2b"
+#   endif
+#   if __cpp_lib_constexpr_typeinfo != 202106L
+#     error "__cpp_lib_constexpr_typeinfo should have the value 202106L in c++2b"
+#   endif
+# else // _LIBCPP_VERSION
+#   ifdef __cpp_lib_constexpr_typeinfo
+#     error "__cpp_lib_constexpr_typeinfo should not be defined because it is unimplemented in libc++!"
+#   endif
+# endif
+
+#endif // TEST_STD_VER > 20
+
+int main(int, char**) { return 0; }

libcxx/test/std/language.support/support.limits/support.limits.general/unordered_map.version.pass.cpp

 // and should not be edited manually.
 //
 // clang-format off
 
 // <unordered_map>
 
 // Test the feature test macros defined by <unordered_map>
 
-/*  Constant                                      Value
-    __cpp_lib_allocator_traits_is_always_equal    201411L [C++17]
-    __cpp_lib_erase_if                            202002L [C++20]
-    __cpp_lib_generic_unordered_lookup            201811L [C++20]
-    __cpp_lib_node_extract                        201606L [C++17]
-    __cpp_lib_nonmember_container_access          201411L [C++17]
-    __cpp_lib_unordered_map_try_emplace           201411L [C++17]
+/*  Constant                                       Value
+    __cpp_lib_allocator_traits_is_always_equal     201411L [C++17]
+    __cpp_lib_associative_heterogeneous_erasure    202110L [C++2b]
+    __cpp_lib_erase_if                             202002L [C++20]
+    __cpp_lib_generic_unordered_lookup             201811L [C++20]
+    __cpp_lib_node_extract                         201606L [C++17]
+    __cpp_lib_nonmember_container_access           201411L [C++17]
+    __cpp_lib_unordered_map_try_emplace            201411L [C++17]
 */
 
 #include <unordered_map>
 #include "test_macros.h"
 
 #if TEST_STD_VER < 14
 
 # ifdef __cpp_lib_allocator_traits_is_always_equal
 #   error "__cpp_lib_allocator_traits_is_always_equal should not be defined before c++17"
 # endif
 
+# ifdef __cpp_lib_associative_heterogeneous_erasure
+#   error "__cpp_lib_associative_heterogeneous_erasure should not be defined before c++2b"
+# endif
+
 # ifdef __cpp_lib_erase_if
 #   error "__cpp_lib_erase_if should not be defined before c++20"
 # endif
 
 # ifdef __cpp_lib_generic_unordered_lookup
 #   error "__cpp_lib_generic_unordered_lookup should not be defined before c++20"
 # endif
 

 # endif
 
 #elif TEST_STD_VER == 14
 
 # ifdef __cpp_lib_allocator_traits_is_always_equal
 #   error "__cpp_lib_allocator_traits_is_always_equal should not be defined before c++17"
 # endif
 
+# ifdef __cpp_lib_associative_heterogeneous_erasure
+#   error "__cpp_lib_associative_heterogeneous_erasure should not be defined before c++2b"
+# endif
+
 # ifdef __cpp_lib_erase_if
 #   error "__cpp_lib_erase_if should not be defined before c++20"
 # endif
 
 # ifdef __cpp_lib_generic_unordered_lookup
 #   error "__cpp_lib_generic_unordered_lookup should not be defined before c++20"
 # endif
 

 
 # ifndef __cpp_lib_allocator_traits_is_always_equal
 #   error "__cpp_lib_allocator_traits_is_always_equal should be defined in c++17"
 # endif
 # if __cpp_lib_allocator_traits_is_always_equal != 201411L
 #   error "__cpp_lib_allocator_traits_is_always_equal should have the value 201411L in c++17"
 # endif
 
+# ifdef __cpp_lib_associative_heterogeneous_erasure
+#   error "__cpp_lib_associative_heterogeneous_erasure should not be defined before c++2b"
+# endif
+
 # ifdef __cpp_lib_erase_if
 #   error "__cpp_lib_erase_if should not be defined before c++20"
 # endif
 
 # ifdef __cpp_lib_generic_unordered_lookup
 #   error "__cpp_lib_generic_unordered_lookup should not be defined before c++20"
 # endif
 

 
 # ifndef __cpp_lib_allocator_traits_is_always_equal
 #   error "__cpp_lib_allocator_traits_is_always_equal should be defined in c++20"
 # endif
 # if __cpp_lib_allocator_traits_is_always_equal != 201411L
 #   error "__cpp_lib_allocator_traits_is_always_equal should have the value 201411L in c++20"
 # endif
 
+# ifdef __cpp_lib_associative_heterogeneous_erasure
+#   error "__cpp_lib_associative_heterogeneous_erasure should not be defined before c++2b"
+# endif
+
 # ifndef __cpp_lib_erase_if
 #   error "__cpp_lib_erase_if should be defined in c++20"
 # endif
 # if __cpp_lib_erase_if != 202002L
 #   error "__cpp_lib_erase_if should have the value 202002L in c++20"
 # endif
 
 # ifndef __cpp_lib_generic_unordered_lookup

 
 # ifndef __cpp_lib_allocator_traits_is_always_equal
 #   error "__cpp_lib_allocator_traits_is_always_equal should be defined in c++2b"
 # endif
 # if __cpp_lib_allocator_traits_is_always_equal != 201411L
 #   error "__cpp_lib_allocator_traits_is_always_equal should have the value 201411L in c++2b"
 # endif
 
+# if !defined(_LIBCPP_VERSION)
+#   ifndef __cpp_lib_associative_heterogeneous_erasure
+#     error "__cpp_lib_associative_heterogeneous_erasure should be defined in c++2b"
+#   endif
+#   if __cpp_lib_associative_heterogeneous_erasure != 202110L
+#     error "__cpp_lib_associative_heterogeneous_erasure should have the value 202110L in c++2b"
+#   endif
+# else // _LIBCPP_VERSION
+#   ifdef __cpp_lib_associative_heterogeneous_erasure
+#     error "__cpp_lib_associative_heterogeneous_erasure should not be defined because it is unimplemented in libc++!"
+#   endif
+# endif
+
 # ifndef __cpp_lib_erase_if
 #   error "__cpp_lib_erase_if should be defined in c++2b"
 # endif
 # if __cpp_lib_erase_if != 202002L
 #   error "__cpp_lib_erase_if should have the value 202002L in c++2b"
 # endif
 
 # ifndef __cpp_lib_generic_unordered_lookup

libcxx/test/std/language.support/support.limits/support.limits.general/unordered_set.version.pass.cpp

 // and should not be edited manually.
 //
 // clang-format off
 
 // <unordered_set>
 
 // Test the feature test macros defined by <unordered_set>
 
-/*  Constant                                      Value
-    __cpp_lib_allocator_traits_is_always_equal    201411L [C++17]
-    __cpp_lib_erase_if                            202002L [C++20]
-    __cpp_lib_generic_unordered_lookup            201811L [C++20]
-    __cpp_lib_node_extract                        201606L [C++17]
-    __cpp_lib_nonmember_container_access          201411L [C++17]
+/*  Constant                                       Value
+    __cpp_lib_allocator_traits_is_always_equal     201411L [C++17]
+    __cpp_lib_associative_heterogeneous_erasure    202110L [C++2b]
+    __cpp_lib_erase_if                             202002L [C++20]
+    __cpp_lib_generic_unordered_lookup             201811L [C++20]
+    __cpp_lib_node_extract                         201606L [C++17]
+    __cpp_lib_nonmember_container_access           201411L [C++17]
 */
 
 #include <unordered_set>
 #include "test_macros.h"
 
 #if TEST_STD_VER < 14
 
 # ifdef __cpp_lib_allocator_traits_is_always_equal
 #   error "__cpp_lib_allocator_traits_is_always_equal should not be defined before c++17"
 # endif
 
+# ifdef __cpp_lib_associative_heterogeneous_erasure
+#   error "__cpp_lib_associative_heterogeneous_erasure should not be defined before c++2b"
+# endif
+
 # ifdef __cpp_lib_erase_if
 #   error "__cpp_lib_erase_if should not be defined before c++20"
 # endif
 
 # ifdef __cpp_lib_generic_unordered_lookup
 #   error "__cpp_lib_generic_unordered_lookup should not be defined before c++20"
 # endif
 
 # ifdef __cpp_lib_node_extract
 #   error "__cpp_lib_node_extract should not be defined before c++17"
 # endif
 
 # ifdef __cpp_lib_nonmember_container_access
 #   error "__cpp_lib_nonmember_container_access should not be defined before c++17"
 # endif
 
 #elif TEST_STD_VER == 14
 
 # ifdef __cpp_lib_allocator_traits_is_always_equal
 #   error "__cpp_lib_allocator_traits_is_always_equal should not be defined before c++17"
 # endif
 
+# ifdef __cpp_lib_associative_heterogeneous_erasure
+#   error "__cpp_lib_associative_heterogeneous_erasure should not be defined before c++2b"
+# endif
+
 # ifdef __cpp_lib_erase_if
 #   error "__cpp_lib_erase_if should not be defined before c++20"
 # endif
 
 # ifdef __cpp_lib_generic_unordered_lookup
 #   error "__cpp_lib_generic_unordered_lookup should not be defined before c++20"
 # endif
 

 
 # ifndef __cpp_lib_allocator_traits_is_always_equal
 #   error "__cpp_lib_allocator_traits_is_always_equal should be defined in c++17"
 # endif
 # if __cpp_lib_allocator_traits_is_always_equal != 201411L
 #   error "__cpp_lib_allocator_traits_is_always_equal should have the value 201411L in c++17"
 # endif
 
+# ifdef __cpp_lib_associative_heterogeneous_erasure
+#   error "__cpp_lib_associative_heterogeneous_erasure should not be defined before c++2b"
+# endif
+
 # ifdef __cpp_lib_erase_if
 #   error "__cpp_lib_erase_if should not be defined before c++20"
 # endif
 
 # ifdef __cpp_lib_generic_unordered_lookup
 #   error "__cpp_lib_generic_unordered_lookup should not be defined before c++20"
 # endif
 

 
 # ifndef __cpp_lib_allocator_traits_is_always_equal
 #   error "__cpp_lib_allocator_traits_is_always_equal should be defined in c++20"
 # endif
 # if __cpp_lib_allocator_traits_is_always_equal != 201411L
 #   error "__cpp_lib_allocator_traits_is_always_equal should have the value 201411L in c++20"
 # endif
 
+# ifdef __cpp_lib_associative_heterogeneous_erasure
+#   error "__cpp_lib_associative_heterogeneous_erasure should not be defined before c++2b"
+# endif
+
 # ifndef __cpp_lib_erase_if
 #   error "__cpp_lib_erase_if should be defined in c++20"
 # endif
 # if __cpp_lib_erase_if != 202002L
 #   error "__cpp_lib_erase_if should have the value 202002L in c++20"
 # endif
 
 # ifndef __cpp_lib_generic_unordered_lookup

 
 # ifndef __cpp_lib_allocator_traits_is_always_equal
 #   error "__cpp_lib_allocator_traits_is_always_equal should be defined in c++2b"
 # endif
 # if __cpp_lib_allocator_traits_is_always_equal != 201411L
 #   error "__cpp_lib_allocator_traits_is_always_equal should have the value 201411L in c++2b"
 # endif
 
+# if !defined(_LIBCPP_VERSION)
+#   ifndef __cpp_lib_associative_heterogeneous_erasure
+#     error "__cpp_lib_associative_heterogeneous_erasure should be defined in c++2b"
+#   endif
+#   if __cpp_lib_associative_heterogeneous_erasure != 202110L
+#     error "__cpp_lib_associative_heterogeneous_erasure should have the value 202110L in c++2b"
+#   endif
+# else // _LIBCPP_VERSION
+#   ifdef __cpp_lib_associative_heterogeneous_erasure
+#     error "__cpp_lib_associative_heterogeneous_erasure should not be defined because it is unimplemented in libc++!"
+#   endif
+# endif
+
 # ifndef __cpp_lib_erase_if
 #   error "__cpp_lib_erase_if should be defined in c++2b"
 # endif
 # if __cpp_lib_erase_if != 202002L
 #   error "__cpp_lib_erase_if should have the value 202002L in c++2b"
 # endif
 
 # ifndef __cpp_lib_generic_unordered_lookup

libcxx/test/std/language.support/support.limits/support.limits.general/utility.version.pass.cpp

 // Test the feature test macros defined by <utility>
 
 /*  Constant                                  Value
     __cpp_lib_as_const                        201510L [C++17]
     __cpp_lib_constexpr_utility               201811L [C++20]
     __cpp_lib_exchange_function               201304L [C++14]
     __cpp_lib_integer_comparison_functions    202002L [C++20]
     __cpp_lib_integer_sequence                201304L [C++14]
+    __cpp_lib_ranges_zip                      202110L [C++2b]
     __cpp_lib_to_underlying                   202102L [C++2b]
     __cpp_lib_tuples_by_type                  201304L [C++14]
 */
 
 #include <utility>
 #include "test_macros.h"
 
 #if TEST_STD_VER < 14

 # ifdef __cpp_lib_integer_comparison_functions
 #   error "__cpp_lib_integer_comparison_functions should not be defined before c++20"
 # endif
 
 # ifdef __cpp_lib_integer_sequence
 #   error "__cpp_lib_integer_sequence should not be defined before c++14"
 # endif
 
+# ifdef __cpp_lib_ranges_zip
+#   error "__cpp_lib_ranges_zip should not be defined before c++2b"
+# endif
+
 # ifdef __cpp_lib_to_underlying
 #   error "__cpp_lib_to_underlying should not be defined before c++2b"
 # endif
 
 # ifdef __cpp_lib_tuples_by_type
 #   error "__cpp_lib_tuples_by_type should not be defined before c++14"
 # endif
 

 
 # ifndef __cpp_lib_integer_sequence
 #   error "__cpp_lib_integer_sequence should be defined in c++14"
 # endif
 # if __cpp_lib_integer_sequence != 201304L
 #   error "__cpp_lib_integer_sequence should have the value 201304L in c++14"
 # endif
 
+# ifdef __cpp_lib_ranges_zip
+#   error "__cpp_lib_ranges_zip should not be defined before c++2b"
+# endif
+
 # ifdef __cpp_lib_to_underlying
 #   error "__cpp_lib_to_underlying should not be defined before c++2b"
 # endif
 
 # ifndef __cpp_lib_tuples_by_type
 #   error "__cpp_lib_tuples_by_type should be defined in c++14"
 # endif
 # if __cpp_lib_tuples_by_type != 201304L

 
 # ifndef __cpp_lib_integer_sequence
 #   error "__cpp_lib_integer_sequence should be defined in c++17"
 # endif
 # if __cpp_lib_integer_sequence != 201304L
 #   error "__cpp_lib_integer_sequence should have the value 201304L in c++17"
 # endif
 
+# ifdef __cpp_lib_ranges_zip
+#   error "__cpp_lib_ranges_zip should not be defined before c++2b"
+# endif
+
 # ifdef __cpp_lib_to_underlying
 #   error "__cpp_lib_to_underlying should not be defined before c++2b"
 # endif
 
 # ifndef __cpp_lib_tuples_by_type
 #   error "__cpp_lib_tuples_by_type should be defined in c++17"
 # endif
 # if __cpp_lib_tuples_by_type != 201304L

 
 # ifndef __cpp_lib_integer_sequence
 #   error "__cpp_lib_integer_sequence should be defined in c++20"
 # endif
 # if __cpp_lib_integer_sequence != 201304L
 #   error "__cpp_lib_integer_sequence should have the value 201304L in c++20"
 # endif
 
+# ifdef __cpp_lib_ranges_zip
+#   error "__cpp_lib_ranges_zip should not be defined before c++2b"
+# endif
+
 # ifdef __cpp_lib_to_underlying
 #   error "__cpp_lib_to_underlying should not be defined before c++2b"
 # endif
 
 # ifndef __cpp_lib_tuples_by_type
 #   error "__cpp_lib_tuples_by_type should be defined in c++20"
 # endif
 # if __cpp_lib_tuples_by_type != 201304L

 
 # ifndef __cpp_lib_integer_sequence
 #   error "__cpp_lib_integer_sequence should be defined in c++2b"
 # endif
 # if __cpp_lib_integer_sequence != 201304L
 #   error "__cpp_lib_integer_sequence should have the value 201304L in c++2b"
 # endif
 
+# if !defined(_LIBCPP_VERSION)
+#   ifndef __cpp_lib_ranges_zip
+#     error "__cpp_lib_ranges_zip should be defined in c++2b"
+#   endif
+#   if __cpp_lib_ranges_zip != 202110L
+#     error "__cpp_lib_ranges_zip should have the value 202110L in c++2b"
+#   endif
+# else // _LIBCPP_VERSION
+#   ifdef __cpp_lib_ranges_zip
+#     error "__cpp_lib_ranges_zip should not be defined because it is unimplemented in libc++!"
+#   endif
+# endif
+
 # ifndef __cpp_lib_to_underlying
 #   error "__cpp_lib_to_underlying should be defined in c++2b"
 # endif
 # if __cpp_lib_to_underlying != 202102L
 #   error "__cpp_lib_to_underlying should have the value 202102L in c++2b"
 # endif
 
 # ifndef __cpp_lib_tuples_by_type

libcxx/test/std/language.support/support.limits/support.limits.general/version.version.pass.cpp

 // clang-format off
 
 // <version>
 
 // Test the feature test macros defined by <version>
 
 /*  Constant                                       Value
     __cpp_lib_addressof_constexpr                  201603L [C++17]
+    __cpp_lib_allocate_at_least                    202106L [C++2b]
     __cpp_lib_allocator_traits_is_always_equal     201411L [C++17]
     __cpp_lib_any                                  201606L [C++17]
     __cpp_lib_apply                                201603L [C++17]
     __cpp_lib_array_constexpr                      201603L [C++17]
                                                    201811L [C++20]
     __cpp_lib_as_const                             201510L [C++17]
+    __cpp_lib_associative_heterogeneous_erasure    202110L [C++2b]
     __cpp_lib_assume_aligned                       201811L [C++20]
     __cpp_lib_atomic_flag_test                     201907L [C++20]
     __cpp_lib_atomic_float                         201711L [C++20]
     __cpp_lib_atomic_is_always_lock_free           201603L [C++17]
     __cpp_lib_atomic_lock_free_type_aliases        201907L [C++20]
     __cpp_lib_atomic_ref                           201806L [C++20]
     __cpp_lib_atomic_shared_ptr                    201711L [C++20]
     __cpp_lib_atomic_value_initialization          201911L [C++20]
/*  Constant                                       Value
     __cpp_lib_constexpr_dynamic_alloc              201907L [C++20]
     __cpp_lib_constexpr_functional                 201907L [C++20]
     __cpp_lib_constexpr_iterator                   201811L [C++20]
     __cpp_lib_constexpr_memory                     201811L [C++20]
     __cpp_lib_constexpr_numeric                    201911L [C++20]
     __cpp_lib_constexpr_string                     201811L [C++20]
     __cpp_lib_constexpr_string_view                201811L [C++20]
     __cpp_lib_constexpr_tuple                      201811L [C++20]
+    __cpp_lib_constexpr_typeinfo                   202106L [C++2b]
     __cpp_lib_constexpr_utility                    201811L [C++20]
     __cpp_lib_constexpr_vector                     201907L [C++20]
     __cpp_lib_coroutine                            201902L [C++20]
     __cpp_lib_destroying_delete                    201806L [C++20]
     __cpp_lib_enable_shared_from_this              201603L [C++17]
     __cpp_lib_endian                               201907L [C++20]
     __cpp_lib_erase_if                             202002L [C++20]
     __cpp_lib_exchange_function                    201304L [C++14]
/*  Constant                                       Value
     __cpp_lib_hypot                                201603L [C++17]
     __cpp_lib_incomplete_container_elements        201505L [C++17]
     __cpp_lib_int_pow2                             202002L [C++20]
     __cpp_lib_integer_comparison_functions         202002L [C++20]
     __cpp_lib_integer_sequence                     201304L [C++14]
     __cpp_lib_integral_constant_callable           201304L [C++14]
     __cpp_lib_interpolate                          201902L [C++20]
     __cpp_lib_invoke                               201411L [C++17]
+    __cpp_lib_invoke_r                             202106L [C++2b]
     __cpp_lib_is_aggregate                         201703L [C++17]
     __cpp_lib_is_constant_evaluated                201811L [C++20]
     __cpp_lib_is_final                             201402L [C++14]
     __cpp_lib_is_invocable                         201703L [C++17]
     __cpp_lib_is_layout_compatible                 201907L [C++20]
     __cpp_lib_is_nothrow_convertible               201806L [C++20]
     __cpp_lib_is_null_pointer                      201309L [C++14]
     __cpp_lib_is_pointer_interconvertible          201907L [C++20]
     __cpp_lib_is_scoped_enum                       202011L [C++2b]
     __cpp_lib_is_swappable                         201603L [C++17]
     __cpp_lib_jthread                              201911L [C++20]
     __cpp_lib_latch                                201907L [C++20]
     __cpp_lib_launder                              201606L [C++17]
     __cpp_lib_list_remove_return_type              201806L [C++20]
     __cpp_lib_logical_traits                       201510L [C++17]
     __cpp_lib_make_from_tuple                      201606L [C++17]
     __cpp_lib_make_reverse_iterator                201402L [C++14]
     __cpp_lib_make_unique                          201304L [C++14]
     __cpp_lib_map_try_emplace                      201411L [C++17]
     __cpp_lib_math_constants                       201907L [C++20]
     __cpp_lib_math_special_functions               201603L [C++17]
     __cpp_lib_memory_resource                      201603L [C++17]
     __cpp_lib_monadic_optional                     202110L [C++2b]
+    __cpp_lib_move_only_function                   202110L [C++2b]
     __cpp_lib_node_extract                         201606L [C++17]
     __cpp_lib_nonmember_container_access           201411L [C++17]
     __cpp_lib_not_fn                               201603L [C++17]
     __cpp_lib_null_iterators                       201304L [C++14]
     __cpp_lib_optional                             201606L [C++17]
+    __cpp_lib_out_ptr                              202106L [C++2b]
     __cpp_lib_parallel_algorithm                   201603L [C++17]
     __cpp_lib_polymorphic_allocator                201902L [C++20]
     __cpp_lib_quoted_string_io                     201304L [C++14]
     __cpp_lib_ranges                               201811L [C++20]
+    __cpp_lib_ranges_starts_ends_with              202106L [C++2b]
+    __cpp_lib_ranges_zip                           202110L [C++2b]
     __cpp_lib_raw_memory_algorithms                201606L [C++17]
     __cpp_lib_remove_cvref                         201711L [C++20]
     __cpp_lib_result_of_sfinae                     201210L [C++14]
     __cpp_lib_robust_nonmodifying_seq_ops          201304L [C++14]
     __cpp_lib_sample                               201603L [C++17]
     __cpp_lib_scoped_lock                          201703L [C++17]
     __cpp_lib_semaphore                            201907L [C++20]
     __cpp_lib_shared_mutex                         201505L [C++17]
     __cpp_lib_shared_ptr_arrays                    201611L [C++17]
     __cpp_lib_shared_ptr_weak_type                 201606L [C++17]
     __cpp_lib_shared_timed_mutex                   201402L [C++14]
     __cpp_lib_shift                                201806L [C++20]
     __cpp_lib_smart_ptr_for_overwrite              202002L [C++20]
     __cpp_lib_source_location                      201907L [C++20]
     __cpp_lib_span                                 202002L [C++20]
+    __cpp_lib_spanstream                           202106L [C++2b]
     __cpp_lib_ssize                                201902L [C++20]
     __cpp_lib_stacktrace                           202011L [C++2b]
     __cpp_lib_starts_ends_with                     201711L [C++20]
     __cpp_lib_stdatomic_h                          202011L [C++2b]
     __cpp_lib_string_contains                      202011L [C++2b]
     __cpp_lib_string_udls                          201304L [C++14]
     __cpp_lib_string_view                          201606L [C++17]
                                                    201803L [C++20]
     __cpp_lib_syncbuf                              201803L [C++20]
     __cpp_lib_three_way_comparison                 201907L [C++20]
     __cpp_lib_to_address                           201711L [C++20]
     __cpp_lib_to_array                             201907L [C++20]
     __cpp_lib_to_chars                             201611L [C++17]
     __cpp_lib_to_underlying                        202102L [C++2b]
     __cpp_lib_transformation_trait_aliases         201304L [C++14]
     __cpp_lib_transparent_operators                201210L [C++14]
                                                    201510L [C++17]
     __cpp_lib_tuple_element_t                      201402L [C++14]
     __cpp_lib_tuples_by_type                       201304L [C++14]
+    __cpp_lib_type_identity                        201806L [C++20]
     __cpp_lib_type_trait_variable_templates        201510L [C++17]
     __cpp_lib_uncaught_exceptions                  201411L [C++17]
     __cpp_lib_unordered_map_try_emplace            201411L [C++17]
     __cpp_lib_unwrap_ref                           201811L [C++20]
     __cpp_lib_variant                              202102L [C++17]
     __cpp_lib_void_t                               201411L [C++17]
 */
 
 #include <version>
 #include "test_macros.h"
 
 #if TEST_STD_VER < 14
 
 # ifdef __cpp_lib_addressof_constexpr
 #   error "__cpp_lib_addressof_constexpr should not be defined before c++17"
 # endif
 
+# ifdef __cpp_lib_allocate_at_least
+#   error "__cpp_lib_allocate_at_least should not be defined before c++2b"
+# endif
+
 # ifdef __cpp_lib_allocator_traits_is_always_equal
 #   error "__cpp_lib_allocator_traits_is_always_equal should not be defined before c++17"
 # endif
 
 # ifdef __cpp_lib_any
 #   error "__cpp_lib_any should not be defined before c++17"
 # endif
 
 # ifdef __cpp_lib_apply
 #   error "__cpp_lib_apply should not be defined before c++17"
 # endif
 
 # ifdef __cpp_lib_array_constexpr
 #   error "__cpp_lib_array_constexpr should not be defined before c++17"
 # endif
 
 # ifdef __cpp_lib_as_const
 #   error "__cpp_lib_as_const should not be defined before c++17"
 # endif
 
+# ifdef __cpp_lib_associative_heterogeneous_erasure
+#   error "__cpp_lib_associative_heterogeneous_erasure should not be defined before c++2b"
+# endif
+
 # ifdef __cpp_lib_assume_aligned
 #   error "__cpp_lib_assume_aligned should not be defined before c++20"
 # endif
 
 # ifdef __cpp_lib_atomic_flag_test
 #   error "__cpp_lib_atomic_flag_test should not be defined before c++20"
 # endif
 

 # ifdef __cpp_lib_constexpr_string_view
 #   error "__cpp_lib_constexpr_string_view should not be defined before c++20"
 # endif
 
 # ifdef __cpp_lib_constexpr_tuple
 #   error "__cpp_lib_constexpr_tuple should not be defined before c++20"
 # endif
 
+# ifdef __cpp_lib_constexpr_typeinfo
+#   error "__cpp_lib_constexpr_typeinfo should not be defined before c++2b"
+# endif
+
 # ifdef __cpp_lib_constexpr_utility
 #   error "__cpp_lib_constexpr_utility should not be defined before c++20"
 # endif
 
 # ifdef __cpp_lib_constexpr_vector
 #   error "__cpp_lib_constexpr_vector should not be defined before c++20"
 # endif
 

 # ifdef __cpp_lib_interpolate
 #   error "__cpp_lib_interpolate should not be defined before c++20"
 # endif
 
 # ifdef __cpp_lib_invoke
 #   error "__cpp_lib_invoke should not be defined before c++17"
 # endif
 
+# ifdef __cpp_lib_invoke_r
+#   error "__cpp_lib_invoke_r should not be defined before c++2b"
+# endif
+
 # ifdef __cpp_lib_is_aggregate
 #   error "__cpp_lib_is_aggregate should not be defined before c++17"
 # endif
 
 # ifdef __cpp_lib_is_constant_evaluated
 #   error "__cpp_lib_is_constant_evaluated should not be defined before c++20"
 # endif
 

 # ifdef __cpp_lib_memory_resource
 #   error "__cpp_lib_memory_resource should not be defined before c++17"
 # endif
 
 # ifdef __cpp_lib_monadic_optional
 #   error "__cpp_lib_monadic_optional should not be defined before c++2b"
 # endif
 
+# ifdef __cpp_lib_move_only_function
+#   error "__cpp_lib_move_only_function should not be defined before c++2b"
+# endif
+
 # ifdef __cpp_lib_node_extract
 #   error "__cpp_lib_node_extract should not be defined before c++17"
 # endif
 
 # ifdef __cpp_lib_nonmember_container_access
 #   error "__cpp_lib_nonmember_container_access should not be defined before c++17"
 # endif
 
 # ifdef __cpp_lib_not_fn
 #   error "__cpp_lib_not_fn should not be defined before c++17"
 # endif
 
 # ifdef __cpp_lib_null_iterators
 #   error "__cpp_lib_null_iterators should not be defined before c++14"
 # endif
 
 # ifdef __cpp_lib_optional
 #   error "__cpp_lib_optional should not be defined before c++17"
 # endif
 
+# ifdef __cpp_lib_out_ptr
+#   error "__cpp_lib_out_ptr should not be defined before c++2b"
+# endif
+
 # ifdef __cpp_lib_parallel_algorithm
 #   error "__cpp_lib_parallel_algorithm should not be defined before c++17"
 # endif
 
 # ifdef __cpp_lib_polymorphic_allocator
 #   error "__cpp_lib_polymorphic_allocator should not be defined before c++20"
 # endif
 
 # ifdef __cpp_lib_quoted_string_io
 #   error "__cpp_lib_quoted_string_io should not be defined before c++14"
 # endif
 
 # ifdef __cpp_lib_ranges
 #   error "__cpp_lib_ranges should not be defined before c++20"
 # endif
 
+# ifdef __cpp_lib_ranges_starts_ends_with
+#   error "__cpp_lib_ranges_starts_ends_with should not be defined before c++2b"
+# endif
+
+# ifdef __cpp_lib_ranges_zip
+#   error "__cpp_lib_ranges_zip should not be defined before c++2b"
+# endif
+
 # ifdef __cpp_lib_raw_memory_algorithms
 #   error "__cpp_lib_raw_memory_algorithms should not be defined before c++17"
 # endif
 
 # ifdef __cpp_lib_remove_cvref
 #   error "__cpp_lib_remove_cvref should not be defined before c++20"
 # endif
 

 # ifdef __cpp_lib_source_location
 #   error "__cpp_lib_source_location should not be defined before c++20"
 # endif
 
 # ifdef __cpp_lib_span
 #   error "__cpp_lib_span should not be defined before c++20"
 # endif
 
+# ifdef __cpp_lib_spanstream
+#   error "__cpp_lib_spanstream should not be defined before c++2b"
+# endif
+
 # ifdef __cpp_lib_ssize
 #   error "__cpp_lib_ssize should not be defined before c++20"
 # endif
 
 # ifdef __cpp_lib_stacktrace
 #   error "__cpp_lib_stacktrace should not be defined before c++2b"
 # endif
 

 # ifdef __cpp_lib_tuple_element_t
 #   error "__cpp_lib_tuple_element_t should not be defined before c++14"
 # endif
 
 # ifdef __cpp_lib_tuples_by_type
 #   error "__cpp_lib_tuples_by_type should not be defined before c++14"
 # endif
 
+# ifdef __cpp_lib_type_identity
+#   error "__cpp_lib_type_identity should not be defined before c++20"
+# endif
+
 # ifdef __cpp_lib_type_trait_variable_templates
 #   error "__cpp_lib_type_trait_variable_templates should not be defined before c++17"
 # endif
 
 # ifdef __cpp_lib_uncaught_exceptions
 #   error "__cpp_lib_uncaught_exceptions should not be defined before c++17"
 # endif
 

 # endif
 
 #elif TEST_STD_VER == 14
 
 # ifdef __cpp_lib_addressof_constexpr
 #   error "__cpp_lib_addressof_constexpr should not be defined before c++17"
 # endif
 
+# ifdef __cpp_lib_allocate_at_least
+#   error "__cpp_lib_allocate_at_least should not be defined before c++2b"
+# endif
+
 # ifdef __cpp_lib_allocator_traits_is_always_equal
 #   error "__cpp_lib_allocator_traits_is_always_equal should not be defined before c++17"
 # endif
 
 # ifdef __cpp_lib_any
 #   error "__cpp_lib_any should not be defined before c++17"
 # endif
 
 # ifdef __cpp_lib_apply
 #   error "__cpp_lib_apply should not be defined before c++17"
 # endif
 
 # ifdef __cpp_lib_array_constexpr
 #   error "__cpp_lib_array_constexpr should not be defined before c++17"
 # endif
 
 # ifdef __cpp_lib_as_const
 #   error "__cpp_lib_as_const should not be defined before c++17"
 # endif
 
+# ifdef __cpp_lib_associative_heterogeneous_erasure
+#   error "__cpp_lib_associative_heterogeneous_erasure should not be defined before c++2b"
+# endif
+
 # ifdef __cpp_lib_assume_aligned
 #   error "__cpp_lib_assume_aligned should not be defined before c++20"
 # endif
 
 # ifdef __cpp_lib_atomic_flag_test
 #   error "__cpp_lib_atomic_flag_test should not be defined before c++20"
 # endif
 

 # ifdef __cpp_lib_constexpr_string_view
 #   error "__cpp_lib_constexpr_string_view should not be defined before c++20"
 # endif
 
 # ifdef __cpp_lib_constexpr_tuple
 #   error "__cpp_lib_constexpr_tuple should not be defined before c++20"
 # endif
 
+# ifdef __cpp_lib_constexpr_typeinfo
+#   error "__cpp_lib_constexpr_typeinfo should not be defined before c++2b"
+# endif
+
 # ifdef __cpp_lib_constexpr_utility
 #   error "__cpp_lib_constexpr_utility should not be defined before c++20"
 # endif
 
 # ifdef __cpp_lib_constexpr_vector
 #   error "__cpp_lib_constexpr_vector should not be defined before c++20"
 # endif
 

 # ifdef __cpp_lib_interpolate
 #   error "__cpp_lib_interpolate should not be defined before c++20"
 # endif
 
 # ifdef __cpp_lib_invoke
 #   error "__cpp_lib_invoke should not be defined before c++17"
 # endif
 
+# ifdef __cpp_lib_invoke_r
+#   error "__cpp_lib_invoke_r should not be defined before c++2b"
+# endif
+
 # ifdef __cpp_lib_is_aggregate
 #   error "__cpp_lib_is_aggregate should not be defined before c++17"
 # endif
 
 # ifdef __cpp_lib_is_constant_evaluated
 #   error "__cpp_lib_is_constant_evaluated should not be defined before c++20"
 # endif
 

 # ifdef __cpp_lib_memory_resource
 #   error "__cpp_lib_memory_resource should not be defined before c++17"
 # endif
 
 # ifdef __cpp_lib_monadic_optional
 #   error "__cpp_lib_monadic_optional should not be defined before c++2b"
 # endif
 
+# ifdef __cpp_lib_move_only_function
+#   error "__cpp_lib_move_only_function should not be defined before c++2b"
+# endif
+
 # ifdef __cpp_lib_node_extract
 #   error "__cpp_lib_node_extract should not be defined before c++17"
 # endif
 
 # ifdef __cpp_lib_nonmember_container_access
 #   error "__cpp_lib_nonmember_container_access should not be defined before c++17"
 # endif
 
 # ifdef __cpp_lib_not_fn
 #   error "__cpp_lib_not_fn should not be defined before c++17"
 # endif
 
 # ifndef __cpp_lib_null_iterators
 #   error "__cpp_lib_null_iterators should be defined in c++14"
 # endif
 # if __cpp_lib_null_iterators != 201304L
 #   error "__cpp_lib_null_iterators should have the value 201304L in c++14"
 # endif
 
 # ifdef __cpp_lib_optional
 #   error "__cpp_lib_optional should not be defined before c++17"
 # endif
 
+# ifdef __cpp_lib_out_ptr
+#   error "__cpp_lib_out_ptr should not be defined before c++2b"
+# endif
+
 # ifdef __cpp_lib_parallel_algorithm
 #   error "__cpp_lib_parallel_algorithm should not be defined before c++17"
 # endif
 
 # ifdef __cpp_lib_polymorphic_allocator
 #   error "__cpp_lib_polymorphic_allocator should not be defined before c++20"
 # endif
 
 # ifndef __cpp_lib_quoted_string_io
 #   error "__cpp_lib_quoted_string_io should be defined in c++14"
 # endif
 # if __cpp_lib_quoted_string_io != 201304L
 #   error "__cpp_lib_quoted_string_io should have the value 201304L in c++14"
 # endif
 
 # ifdef __cpp_lib_ranges
 #   error "__cpp_lib_ranges should not be defined before c++20"
 # endif
 
+# ifdef __cpp_lib_ranges_starts_ends_with
+#   error "__cpp_lib_ranges_starts_ends_with should not be defined before c++2b"
+# endif
+
+# ifdef __cpp_lib_ranges_zip
+#   error "__cpp_lib_ranges_zip should not be defined before c++2b"
+# endif
+
 # ifdef __cpp_lib_raw_memory_algorithms
 #   error "__cpp_lib_raw_memory_algorithms should not be defined before c++17"
 # endif
 
 # ifdef __cpp_lib_remove_cvref
 #   error "__cpp_lib_remove_cvref should not be defined before c++20"
 # endif
 

 # ifdef __cpp_lib_source_location
 #   error "__cpp_lib_source_location should not be defined before c++20"
 # endif
 
 # ifdef __cpp_lib_span
 #   error "__cpp_lib_span should not be defined before c++20"
 # endif
 
+# ifdef __cpp_lib_spanstream
+#   error "__cpp_lib_spanstream should not be defined before c++2b"
+# endif
+
 # ifdef __cpp_lib_ssize
 #   error "__cpp_lib_ssize should not be defined before c++20"
 # endif
 
 # ifdef __cpp_lib_stacktrace
 #   error "__cpp_lib_stacktrace should not be defined before c++2b"
 # endif
 

 
 # ifndef __cpp_lib_tuples_by_type
 #   error "__cpp_lib_tuples_by_type should be defined in c++14"
 # endif
 # if __cpp_lib_tuples_by_type != 201304L
 #   error "__cpp_lib_tuples_by_type should have the value 201304L in c++14"
 # endif
 
+# ifdef __cpp_lib_type_identity
+#   error "__cpp_lib_type_identity should not be defined before c++20"
+# endif
+
 # ifdef __cpp_lib_type_trait_variable_templates
 #   error "__cpp_lib_type_trait_variable_templates should not be defined before c++17"
 # endif
 
 # ifdef __cpp_lib_uncaught_exceptions
 #   error "__cpp_lib_uncaught_exceptions should not be defined before c++17"
 # endif
 

 
 # ifndef __cpp_lib_addressof_constexpr
 #   error "__cpp_lib_addressof_constexpr should be defined in c++17"
 # endif
 # if __cpp_lib_addressof_constexpr != 201603L
 #   error "__cpp_lib_addressof_constexpr should have the value 201603L in c++17"
 # endif
 
+# ifdef __cpp_lib_allocate_at_least
+#   error "__cpp_lib_allocate_at_least should not be defined before c++2b"
+# endif
+
 # ifndef __cpp_lib_allocator_traits_is_always_equal
 #   error "__cpp_lib_allocator_traits_is_always_equal should be defined in c++17"
 # endif
 # if __cpp_lib_allocator_traits_is_always_equal != 201411L
 #   error "__cpp_lib_allocator_traits_is_always_equal should have the value 201411L in c++17"
 # endif
 
 # ifndef __cpp_lib_any

 
 # ifndef __cpp_lib_as_const
 #   error "__cpp_lib_as_const should be defined in c++17"
 # endif
 # if __cpp_lib_as_const != 201510L
 #   error "__cpp_lib_as_const should have the value 201510L in c++17"
 # endif
 
+# ifdef __cpp_lib_associative_heterogeneous_erasure
+#   error "__cpp_lib_associative_heterogeneous_erasure should not be defined before c++2b"
+# endif
+
 # ifdef __cpp_lib_assume_aligned
 #   error "__cpp_lib_assume_aligned should not be defined before c++20"
 # endif
 
 # ifdef __cpp_lib_atomic_flag_test
 #   error "__cpp_lib_atomic_flag_test should not be defined before c++20"
 # endif
 

 # ifdef __cpp_lib_constexpr_string_view
 #   error "__cpp_lib_constexpr_string_view should not be defined before c++20"
 # endif
 
 # ifdef __cpp_lib_constexpr_tuple
 #   error "__cpp_lib_constexpr_tuple should not be defined before c++20"
 # endif
 
+# ifdef __cpp_lib_constexpr_typeinfo
+#   error "__cpp_lib_constexpr_typeinfo should not be defined before c++2b"
+# endif
+
 # ifdef __cpp_lib_constexpr_utility
 #   error "__cpp_lib_constexpr_utility should not be defined before c++20"
 # endif
 
 # ifdef __cpp_lib_constexpr_vector
 #   error "__cpp_lib_constexpr_vector should not be defined before c++20"
 # endif
 

 
 # ifndef __cpp_lib_invoke
 #   error "__cpp_lib_invoke should be defined in c++17"
 # endif
 # if __cpp_lib_invoke != 201411L
 #   error "__cpp_lib_invoke should have the value 201411L in c++17"
 # endif
 
+# ifdef __cpp_lib_invoke_r
+#   error "__cpp_lib_invoke_r should not be defined before c++2b"
+# endif
+
 # ifndef __cpp_lib_is_aggregate
 #   error "__cpp_lib_is_aggregate should be defined in c++17"
 # endif
 # if __cpp_lib_is_aggregate != 201703L
 #   error "__cpp_lib_is_aggregate should have the value 201703L in c++17"
 # endif
 
 # ifdef __cpp_lib_is_constant_evaluated

 #     error "__cpp_lib_memory_resource should not be defined because it is unimplemented in libc++!"
 #   endif
 # endif
 
 # ifdef __cpp_lib_monadic_optional
 #   error "__cpp_lib_monadic_optional should not be defined before c++2b"
 # endif
 
+# ifdef __cpp_lib_move_only_function
+#   error "__cpp_lib_move_only_function should not be defined before c++2b"
+# endif
+
 # ifndef __cpp_lib_node_extract
 #   error "__cpp_lib_node_extract should be defined in c++17"
 # endif
 # if __cpp_lib_node_extract != 201606L
 #   error "__cpp_lib_node_extract should have the value 201606L in c++17"
 # endif
 
 # ifndef __cpp_lib_nonmember_container_access

 
 # ifndef __cpp_lib_optional
 #   error "__cpp_lib_optional should be defined in c++17"
 # endif
 # if __cpp_lib_optional != 201606L
 #   error "__cpp_lib_optional should have the value 201606L in c++17"
 # endif
 
+# ifdef __cpp_lib_out_ptr
+#   error "__cpp_lib_out_ptr should not be defined before c++2b"
+# endif
+
 # if !defined(_LIBCPP_VERSION)
 #   ifndef __cpp_lib_parallel_algorithm
 #     error "__cpp_lib_parallel_algorithm should be defined in c++17"
 #   endif
 #   if __cpp_lib_parallel_algorithm != 201603L
 #     error "__cpp_lib_parallel_algorithm should have the value 201603L in c++17"
 #   endif
 # else // _LIBCPP_VERSION

 # if __cpp_lib_quoted_string_io != 201304L
 #   error "__cpp_lib_quoted_string_io should have the value 201304L in c++17"
 # endif
 
 # ifdef __cpp_lib_ranges
 #   error "__cpp_lib_ranges should not be defined before c++20"
 # endif
 
+# ifdef __cpp_lib_ranges_starts_ends_with
+#   error "__cpp_lib_ranges_starts_ends_with should not be defined before c++2b"
+# endif
+
+# ifdef __cpp_lib_ranges_zip
+#   error "__cpp_lib_ranges_zip should not be defined before c++2b"
+# endif
+
 # ifndef __cpp_lib_raw_memory_algorithms
 #   error "__cpp_lib_raw_memory_algorithms should be defined in c++17"
 # endif
 # if __cpp_lib_raw_memory_algorithms != 201606L
 #   error "__cpp_lib_raw_memory_algorithms should have the value 201606L in c++17"
 # endif
 
 # ifdef __cpp_lib_remove_cvref

 # ifdef __cpp_lib_source_location
 #   error "__cpp_lib_source_location should not be defined before c++20"
 # endif
 
 # ifdef __cpp_lib_span
 #   error "__cpp_lib_span should not be defined before c++20"
 # endif
 
+# ifdef __cpp_lib_spanstream
+#   error "__cpp_lib_spanstream should not be defined before c++2b"
+# endif
+
 # ifdef __cpp_lib_ssize
 #   error "__cpp_lib_ssize should not be defined before c++20"
 # endif
 
 # ifdef __cpp_lib_stacktrace
 #   error "__cpp_lib_stacktrace should not be defined before c++2b"
 # endif
 

 
 # ifndef __cpp_lib_tuples_by_type
 #   error "__cpp_lib_tuples_by_type should be defined in c++17"
 # endif
 # if __cpp_lib_tuples_by_type != 201304L
 #   error "__cpp_lib_tuples_by_type should have the value 201304L in c++17"
 # endif
 
+# ifdef __cpp_lib_type_identity
+#   error "__cpp_lib_type_identity should not be defined before c++20"
+# endif
+
 # ifndef __cpp_lib_type_trait_variable_templates
 #   error "__cpp_lib_type_trait_variable_templates should be defined in c++17"
 # endif
 # if __cpp_lib_type_trait_variable_templates != 201510L
 #   error "__cpp_lib_type_trait_variable_templates should have the value 201510L in c++17"
 # endif
 
 # ifndef __cpp_lib_uncaught_exceptions

 
 # ifndef __cpp_lib_addressof_constexpr
 #   error "__cpp_lib_addressof_constexpr should be defined in c++20"
 # endif
 # if __cpp_lib_addressof_constexpr != 201603L
 #   error "__cpp_lib_addressof_constexpr should have the value 201603L in c++20"
 # endif
 
+# ifdef __cpp_lib_allocate_at_least
+#   error "__cpp_lib_allocate_at_least should not be defined before c++2b"
+# endif
+
 # ifndef __cpp_lib_allocator_traits_is_always_equal
 #   error "__cpp_lib_allocator_traits_is_always_equal should be defined in c++20"
 # endif
 # if __cpp_lib_allocator_traits_is_always_equal != 201411L
 #   error "__cpp_lib_allocator_traits_is_always_equal should have the value 201411L in c++20"
 # endif
 
 # ifndef __cpp_lib_any

 
 # ifndef __cpp_lib_as_const
 #   error "__cpp_lib_as_const should be defined in c++20"
 # endif
 # if __cpp_lib_as_const != 201510L
 #   error "__cpp_lib_as_const should have the value 201510L in c++20"
 # endif
 
+# ifdef __cpp_lib_associative_heterogeneous_erasure
+#   error "__cpp_lib_associative_heterogeneous_erasure should not be defined before c++2b"
+# endif
+
 # if !defined(_LIBCPP_VERSION)
 #   ifndef __cpp_lib_assume_aligned
 #     error "__cpp_lib_assume_aligned should be defined in c++20"
 #   endif
 #   if __cpp_lib_assume_aligned != 201811L
 #     error "__cpp_lib_assume_aligned should have the value 201811L in c++20"
 #   endif
 # else // _LIBCPP_VERSION

 
 # ifndef __cpp_lib_constexpr_tuple
 #   error "__cpp_lib_constexpr_tuple should be defined in c++20"
 # endif
 # if __cpp_lib_constexpr_tuple != 201811L
 #   error "__cpp_lib_constexpr_tuple should have the value 201811L in c++20"
 # endif
 
+# ifdef __cpp_lib_constexpr_typeinfo
+#   error "__cpp_lib_constexpr_typeinfo should not be defined before c++2b"
+# endif
+
 # ifndef __cpp_lib_constexpr_utility
 #   error "__cpp_lib_constexpr_utility should be defined in c++20"
 # endif
 # if __cpp_lib_constexpr_utility != 201811L
 #   error "__cpp_lib_constexpr_utility should have the value 201811L in c++20"
 # endif
 
 # if !defined(_LIBCPP_VERSION)

 
 # ifndef __cpp_lib_invoke
 #   error "__cpp_lib_invoke should be defined in c++20"
 # endif
 # if __cpp_lib_invoke != 201411L
 #   error "__cpp_lib_invoke should have the value 201411L in c++20"
 # endif
 
+# ifdef __cpp_lib_invoke_r
+#   error "__cpp_lib_invoke_r should not be defined before c++2b"
+# endif
+
 # ifndef __cpp_lib_is_aggregate
 #   error "__cpp_lib_is_aggregate should be defined in c++20"
 # endif
 # if __cpp_lib_is_aggregate != 201703L
 #   error "__cpp_lib_is_aggregate should have the value 201703L in c++20"
 # endif
 
 # ifndef __cpp_lib_is_constant_evaluated

 #     error "__cpp_lib_memory_resource should not be defined because it is unimplemented in libc++!"
 #   endif
 # endif
 
 # ifdef __cpp_lib_monadic_optional
 #   error "__cpp_lib_monadic_optional should not be defined before c++2b"
 # endif
 
+# ifdef __cpp_lib_move_only_function
+#   error "__cpp_lib_move_only_function should not be defined before c++2b"
+# endif
+
 # ifndef __cpp_lib_node_extract
 #   error "__cpp_lib_node_extract should be defined in c++20"
 # endif
 # if __cpp_lib_node_extract != 201606L
 #   error "__cpp_lib_node_extract should have the value 201606L in c++20"
 # endif
 
 # ifndef __cpp_lib_nonmember_container_access

 
 # ifndef __cpp_lib_optional
 #   error "__cpp_lib_optional should be defined in c++20"
 # endif
 # if __cpp_lib_optional != 201606L
 #   error "__cpp_lib_optional should have the value 201606L in c++20"
 # endif
 
+# ifdef __cpp_lib_out_ptr
+#   error "__cpp_lib_out_ptr should not be defined before c++2b"
+# endif
+
 # if !defined(_LIBCPP_VERSION)
 #   ifndef __cpp_lib_parallel_algorithm
 #     error "__cpp_lib_parallel_algorithm should be defined in c++20"
 #   endif
 #   if __cpp_lib_parallel_algorithm != 201603L
 #     error "__cpp_lib_parallel_algorithm should have the value 201603L in c++20"
 #   endif
 # else // _LIBCPP_VERSION

 #     error "__cpp_lib_ranges should have the value 201811L in c++20"
 #   endif
 # else // _LIBCPP_VERSION
 #   ifdef __cpp_lib_ranges
 #     error "__cpp_lib_ranges should not be defined because it is unimplemented in libc++!"
 #   endif
 # endif
 
+# ifdef __cpp_lib_ranges_starts_ends_with
+#   error "__cpp_lib_ranges_starts_ends_with should not be defined before c++2b"
+# endif
+
+# ifdef __cpp_lib_ranges_zip
+#   error "__cpp_lib_ranges_zip should not be defined before c++2b"
+# endif
+
 # ifndef __cpp_lib_raw_memory_algorithms
 #   error "__cpp_lib_raw_memory_algorithms should be defined in c++20"
 # endif
 # if __cpp_lib_raw_memory_algorithms != 201606L
 #   error "__cpp_lib_raw_memory_algorithms should have the value 201606L in c++20"
 # endif
 
 # ifndef __cpp_lib_remove_cvref

 
 # ifndef __cpp_lib_span
 #   error "__cpp_lib_span should be defined in c++20"
 # endif
 # if __cpp_lib_span != 202002L
 #   error "__cpp_lib_span should have the value 202002L in c++20"
 # endif
 
+# ifdef __cpp_lib_spanstream
+#   error "__cpp_lib_spanstream should not be defined before c++2b"
+# endif
+
 # ifndef __cpp_lib_ssize
 #   error "__cpp_lib_ssize should be defined in c++20"
 # endif
 # if __cpp_lib_ssize != 201902L
 #   error "__cpp_lib_ssize should have the value 201902L in c++20"
 # endif
 
 # ifdef __cpp_lib_stacktrace

 
 # ifndef __cpp_lib_tuples_by_type
 #   error "__cpp_lib_tuples_by_type should be defined in c++20"
 # endif
 # if __cpp_lib_tuples_by_type != 201304L
 #   error "__cpp_lib_tuples_by_type should have the value 201304L in c++20"
 # endif
 
+# ifndef __cpp_lib_type_identity
+#   error "__cpp_lib_type_identity should be defined in c++20"
+# endif
+# if __cpp_lib_type_identity != 201806L
+#   error "__cpp_lib_type_identity should have the value 201806L in c++20"
+# endif
+
 # ifndef __cpp_lib_type_trait_variable_templates
 #   error "__cpp_lib_type_trait_variable_templates should be defined in c++20"
 # endif
 # if __cpp_lib_type_trait_variable_templates != 201510L
 #   error "__cpp_lib_type_trait_variable_templates should have the value 201510L in c++20"
 # endif
 
 # ifndef __cpp_lib_uncaught_exceptions

 
 # ifndef __cpp_lib_addressof_constexpr
 #   error "__cpp_lib_addressof_constexpr should be defined in c++2b"
 # endif
 # if __cpp_lib_addressof_constexpr != 201603L
 #   error "__cpp_lib_addressof_constexpr should have the value 201603L in c++2b"
 # endif
 
+# if !defined(_LIBCPP_VERSION)
+#   ifndef __cpp_lib_allocate_at_least
+#     error "__cpp_lib_allocate_at_least should be defined in c++2b"
+#   endif
+#   if __cpp_lib_allocate_at_least != 202106L
+#     error "__cpp_lib_allocate_at_least should have the value 202106L in c++2b"
+#   endif
+# else // _LIBCPP_VERSION
+#   ifdef __cpp_lib_allocate_at_least
+#     error "__cpp_lib_allocate_at_least should not be defined because it is unimplemented in libc++!"
+#   endif
+# endif
+
 # ifndef __cpp_lib_allocator_traits_is_always_equal
 #   error "__cpp_lib_allocator_traits_is_always_equal should be defined in c++2b"
 # endif
 # if __cpp_lib_allocator_traits_is_always_equal != 201411L
 #   error "__cpp_lib_allocator_traits_is_always_equal should have the value 201411L in c++2b"
 # endif
 
 # ifndef __cpp_lib_any

 # ifndef __cpp_lib_as_const
 #   error "__cpp_lib_as_const should be defined in c++2b"
 # endif
 # if __cpp_lib_as_const != 201510L
 #   error "__cpp_lib_as_const should have the value 201510L in c++2b"
 # endif
 
 # if !defined(_LIBCPP_VERSION)
+#   ifndef __cpp_lib_associative_heterogeneous_erasure
+#     error "__cpp_lib_associative_heterogeneous_erasure should be defined in c++2b"
+#   endif
+#   if __cpp_lib_associative_heterogeneous_erasure != 202110L
+#     error "__cpp_lib_associative_heterogeneous_erasure should have the value 202110L in c++2b"
+#   endif
+# else // _LIBCPP_VERSION
+#   ifdef __cpp_lib_associative_heterogeneous_erasure
+#     error "__cpp_lib_associative_heterogeneous_erasure should not be defined because it is unimplemented in libc++!"
+#   endif
+# endif
+
+# if !defined(_LIBCPP_VERSION)
 #   ifndef __cpp_lib_assume_aligned
 #     error "__cpp_lib_assume_aligned should be defined in c++2b"
 #   endif
 #   if __cpp_lib_assume_aligned != 201811L
 #     error "__cpp_lib_assume_aligned should have the value 201811L in c++2b"
 #   endif
 # else // _LIBCPP_VERSION
 #   ifdef __cpp_lib_assume_aligned

 
 # ifndef __cpp_lib_constexpr_tuple
 #   error "__cpp_lib_constexpr_tuple should be defined in c++2b"
 # endif
 # if __cpp_lib_constexpr_tuple != 201811L
 #   error "__cpp_lib_constexpr_tuple should have the value 201811L in c++2b"
 # endif
 
+# if !defined(_LIBCPP_VERSION)
+#   ifndef __cpp_lib_constexpr_typeinfo
+#     error "__cpp_lib_constexpr_typeinfo should be defined in c++2b"
+#   endif
+#   if __cpp_lib_constexpr_typeinfo != 202106L
+#     error "__cpp_lib_constexpr_typeinfo should have the value 202106L in c++2b"
+#   endif
+# else // _LIBCPP_VERSION
+#   ifdef __cpp_lib_constexpr_typeinfo
+#     error "__cpp_lib_constexpr_typeinfo should not be defined because it is unimplemented in libc++!"
+#   endif
+# endif
+
 # ifndef __cpp_lib_constexpr_utility
 #   error "__cpp_lib_constexpr_utility should be defined in c++2b"
 # endif
 # if __cpp_lib_constexpr_utility != 201811L
 #   error "__cpp_lib_constexpr_utility should have the value 201811L in c++2b"
 # endif
 
 # if !defined(_LIBCPP_VERSION)

 
 # ifndef __cpp_lib_invoke
 #   error "__cpp_lib_invoke should be defined in c++2b"
 # endif
 # if __cpp_lib_invoke != 201411L
 #   error "__cpp_lib_invoke should have the value 201411L in c++2b"
 # endif
 
+# if !defined(_LIBCPP_VERSION)
+#   ifndef __cpp_lib_invoke_r
+#     error "__cpp_lib_invoke_r should be defined in c++2b"
+#   endif
+#   if __cpp_lib_invoke_r != 202106L
+#     error "__cpp_lib_invoke_r should have the value 202106L in c++2b"
+#   endif
+# else // _LIBCPP_VERSION
+#   ifdef __cpp_lib_invoke_r
+#     error "__cpp_lib_invoke_r should not be defined because it is unimplemented in libc++!"
+#   endif
+# endif
+
 # ifndef __cpp_lib_is_aggregate
 #   error "__cpp_lib_is_aggregate should be defined in c++2b"
 # endif
 # if __cpp_lib_is_aggregate != 201703L
 #   error "__cpp_lib_is_aggregate should have the value 201703L in c++2b"
 # endif
 
 # ifndef __cpp_lib_is_constant_evaluated

 
 # ifndef __cpp_lib_monadic_optional
 #   error "__cpp_lib_monadic_optional should be defined in c++2b"
 # endif
 # if __cpp_lib_monadic_optional != 202110L
 #   error "__cpp_lib_monadic_optional should have the value 202110L in c++2b"
 # endif
 
+# if !defined(_LIBCPP_VERSION)
+#   ifndef __cpp_lib_move_only_function
+#     error "__cpp_lib_move_only_function should be defined in c++2b"
+#   endif
+#   if __cpp_lib_move_only_function != 202110L
+#     error "__cpp_lib_move_only_function should have the value 202110L in c++2b"
+#   endif
+# else // _LIBCPP_VERSION
+#   ifdef __cpp_lib_move_only_function
+#     error "__cpp_lib_move_only_function should not be defined because it is unimplemented in libc++!"
+#   endif
+# endif
+
 # ifndef __cpp_lib_node_extract
 #   error "__cpp_lib_node_extract should be defined in c++2b"
 # endif
 # if __cpp_lib_node_extract != 201606L
 #   error "__cpp_lib_node_extract should have the value 201606L in c++2b"
 # endif
 
 # ifndef __cpp_lib_nonmember_container_access

 # ifndef __cpp_lib_optional
 #   error "__cpp_lib_optional should be defined in c++2b"
 # endif
 # if __cpp_lib_optional != 201606L
 #   error "__cpp_lib_optional should have the value 201606L in c++2b"
 # endif
 
 # if !defined(_LIBCPP_VERSION)
+#   ifndef __cpp_lib_out_ptr
+#     error "__cpp_lib_out_ptr should be defined in c++2b"
+#   endif
+#   if __cpp_lib_out_ptr != 202106L
+#     error "__cpp_lib_out_ptr should have the value 202106L in c++2b"
+#   endif
+# else // _LIBCPP_VERSION
+#   ifdef __cpp_lib_out_ptr
+#     error "__cpp_lib_out_ptr should not be defined because it is unimplemented in libc++!"
+#   endif
+# endif
+
+# if !defined(_LIBCPP_VERSION)
 #   ifndef __cpp_lib_parallel_algorithm
 #     error "__cpp_lib_parallel_algorithm should be defined in c++2b"
 #   endif
 #   if __cpp_lib_parallel_algorithm != 201603L
 #     error "__cpp_lib_parallel_algorithm should have the value 201603L in c++2b"
 #   endif
 # else // _LIBCPP_VERSION
 #   ifdef __cpp_lib_parallel_algorithm

 #     error "__cpp_lib_ranges should have the value 201811L in c++2b"
 #   endif
 # else // _LIBCPP_VERSION
 #   ifdef __cpp_lib_ranges
 #     error "__cpp_lib_ranges should not be defined because it is unimplemented in libc++!"
 #   endif
 # endif
 
+# if !defined(_LIBCPP_VERSION)
+#   ifndef __cpp_lib_ranges_starts_ends_with
+#     error "__cpp_lib_ranges_starts_ends_with should be defined in c++2b"
+#   endif
+#   if __cpp_lib_ranges_starts_ends_with != 202106L
+#     error "__cpp_lib_ranges_starts_ends_with should have the value 202106L in c++2b"
+#   endif
+# else // _LIBCPP_VERSION
+#   ifdef __cpp_lib_ranges_starts_ends_with
+#     error "__cpp_lib_ranges_starts_ends_with should not be defined because it is unimplemented in libc++!"
+#   endif
+# endif
+
+# if !defined(_LIBCPP_VERSION)
+#   ifndef __cpp_lib_ranges_zip
+#     error "__cpp_lib_ranges_zip should be defined in c++2b"
+#   endif
+#   if __cpp_lib_ranges_zip != 202110L
+#     error "__cpp_lib_ranges_zip should have the value 202110L in c++2b"
+#   endif
+# else // _LIBCPP_VERSION
+#   ifdef __cpp_lib_ranges_zip
+#     error "__cpp_lib_ranges_zip should not be defined because it is unimplemented in libc++!"
+#   endif
+# endif
+
 # ifndef __cpp_lib_raw_memory_algorithms
 #   error "__cpp_lib_raw_memory_algorithms should be defined in c++2b"
 # endif
 # if __cpp_lib_raw_memory_algorithms != 201606L
 #   error "__cpp_lib_raw_memory_algorithms should have the value 201606L in c++2b"
 # endif
 
 # ifndef __cpp_lib_remove_cvref

 
 # ifndef __cpp_lib_span
 #   error "__cpp_lib_span should be defined in c++2b"
 # endif
 # if __cpp_lib_span != 202002L
 #   error "__cpp_lib_span should have the value 202002L in c++2b"
 # endif
 
+# if !defined(_LIBCPP_VERSION)
+#   ifndef __cpp_lib_spanstream
+#     error "__cpp_lib_spanstream should be defined in c++2b"
+#   endif
+#   if __cpp_lib_spanstream != 202106L
+#     error "__cpp_lib_spanstream should have the value 202106L in c++2b"
+#   endif
+# else // _LIBCPP_VERSION
+#   ifdef __cpp_lib_spanstream
+#     error "__cpp_lib_spanstream should not be defined because it is unimplemented in libc++!"
+#   endif
+# endif
+
 # ifndef __cpp_lib_ssize
 #   error "__cpp_lib_ssize should be defined in c++2b"
 # endif
 # if __cpp_lib_ssize != 201902L
 #   error "__cpp_lib_ssize should have the value 201902L in c++2b"
 # endif
 
 # if !defined(_LIBCPP_VERSION)

 
 # ifndef __cpp_lib_tuples_by_type
 #   error "__cpp_lib_tuples_by_type should be defined in c++2b"
 # endif
 # if __cpp_lib_tuples_by_type != 201304L
 #   error "__cpp_lib_tuples_by_type should have the value 201304L in c++2b"
 # endif
 
+# ifndef __cpp_lib_type_identity
+#   error "__cpp_lib_type_identity should be defined in c++2b"
+# endif
+# if __cpp_lib_type_identity != 201806L
+#   error "__cpp_lib_type_identity should have the value 201806L in c++2b"
+# endif
+
 # ifndef __cpp_lib_type_trait_variable_templates
 #   error "__cpp_lib_type_trait_variable_templates should be defined in c++2b"
 # endif
 # if __cpp_lib_type_trait_variable_templates != 201510L
 #   error "__cpp_lib_type_trait_variable_templates should have the value 201510L in c++2b"
 # endif
 
 # ifndef __cpp_lib_uncaught_exceptions

libcxx/utils/generate_feature_test_macro_components.py

 #                   this field.
 # ================  ============================================================
 feature_test_macros = [ add_version_header(x) for x in [
   {
     "name": "__cpp_lib_addressof_constexpr",
     "values": { "c++17": 201603 },
     "headers": ["memory"],
   }, {
+    "name": "__cpp_lib_allocate_at_least",
+    "values": { "c++2b": 202106 },
+    "headers": ["memory"],
+    "unimplemented": True,
+  }, {
     "name": "__cpp_lib_allocator_traits_is_always_equal",
     "values": { "c++17": 201411 },
     "headers": ["deque", "forward_list", "list", "map", "memory", "scoped_allocator", "set", "string", "unordered_map", "unordered_set", "vector"],
   }, {
     "name": "__cpp_lib_any",
     "values": { "c++17": 201606 },
     "headers": ["any"],
   }, {
     "name": "__cpp_lib_apply",
     "values": { "c++17": 201603 },
     "headers": ["tuple"],
   }, {
     "name": "__cpp_lib_array_constexpr",
     "values": { "c++17": 201603, "c++20": 201811 },
     "headers": ["array", "iterator"],
   }, {
     "name": "__cpp_lib_as_const",
     "values": { "c++17": 201510 },
     "headers": ["utility"],
   }, {
+    "name": "__cpp_lib_associative_heterogeneous_erasure",
+    "values": { "c++2b": 202110 },
+    "headers": ["map", "set", "unordered_map", "unordered_set"],
+    "unimplemented": True,
+  }, {
     "name": "__cpp_lib_assume_aligned",
     "values": { "c++20": 201811 },
     "headers": ["memory"],
     "unimplemented": True,
   }, {
     "name": "__cpp_lib_atomic_flag_test",
     "values": { "c++20": 201907 },
     "headers": ["atomic"],
feature_test_macros = [ add_version_header(x) for x in [
     "name": "__cpp_lib_constexpr_string_view",
     "values": { "c++20": 201811 },
     "headers": ["string_view"],
   }, {
     "name": "__cpp_lib_constexpr_tuple",
     "values": { "c++20": 201811 },
     "headers": ["tuple"],
   }, {
+    "name": "__cpp_lib_constexpr_typeinfo",
+    "values": { "c++2b": 202106 },
+    "headers": ["typeinfo"],
+    "unimplemented": True,
+  }, {
     "name": "__cpp_lib_constexpr_utility",
     "values": { "c++20": 201811 },
     "headers": ["utility"],
   }, {
     "name": "__cpp_lib_constexpr_vector",
     "values": { "c++20": 201907 },
     "headers": ["vector"],
     "unimplemented": True,
feature_test_macros = [ add_version_header(x) for x in [
     "name": "__cpp_lib_interpolate",
     "values": { "c++20": 201902 },
     "headers": ["cmath", "numeric"],
   }, {
     "name": "__cpp_lib_invoke",
     "values": { "c++17": 201411 },
     "headers": ["functional"],
   }, {
+    "name": "__cpp_lib_invoke_r",
+    "values": { "c++2b": 202106 },
+    "headers": ["functional"],
+    "unimplemented": True,
+  }, {
     "name": "__cpp_lib_is_aggregate",
     "values": { "c++17": 201703 },
     "headers": ["type_traits"],
   }, {
     "name": "__cpp_lib_is_constant_evaluated",
     "values": { "c++20": 201811 },
     "headers": ["type_traits"],
   }, {
feature_test_macros = [ add_version_header(x) for x in [
     "values": { "c++17": 201603 },
     "headers": ["memory_resource"],
     "unimplemented": True,
   }, {
     "name": "__cpp_lib_monadic_optional",
     "values": { "c++2b": 202110 },
     "headers": ["optional"],
   }, {
+    "name": "__cpp_lib_move_only_function",
+    "values": { "c++2b": 202110 },
+    "headers": ["functional"],
+    "unimplemented": True,
+  }, {
     "name": "__cpp_lib_node_extract",
     "values": { "c++17": 201606 },
     "headers": ["map", "set", "unordered_map", "unordered_set"],
   }, {
     "name": "__cpp_lib_nonmember_container_access",
     "values": { "c++17": 201411 },
     "headers": ["array", "deque", "forward_list", "iterator", "list", "map", "regex", "set", "string", "unordered_map", "unordered_set", "vector"],
   }, {
     "name": "__cpp_lib_not_fn",
     "values": { "c++17": 201603 },
     "headers": ["functional"],
   }, {
     "name": "__cpp_lib_null_iterators",
     "values": { "c++14": 201304 },
     "headers": ["iterator"],
   }, {
     "name": "__cpp_lib_optional",
     "values": { "c++17": 201606 },
     "headers": ["optional"],
   }, {
+    "name": "__cpp_lib_out_ptr",
+    "values": { "c++2b": 202106 },
+    "headers": ["memory"],
+    "unimplemented": True,
+  }, {
     "name": "__cpp_lib_parallel_algorithm",
     "values": { "c++17": 201603 },
     "headers": ["algorithm", "numeric"],
     "unimplemented": True,
   }, {
     "name": "__cpp_lib_polymorphic_allocator",
     "values": { "c++20": 201902 },
     "headers": ["memory"],
     "unimplemented": True,
   }, {
     "name": "__cpp_lib_quoted_string_io",
     "values": { "c++14": 201304 },
     "headers": ["iomanip"],
   }, {
     "name": "__cpp_lib_ranges",
     "values": { "c++20": 201811 },
     "headers": ["algorithm", "functional", "iterator", "memory", "ranges"],
     "unimplemented": True,
   }, {
+    "name": "__cpp_lib_ranges_starts_ends_with",
+    "values": { "c++2b": 202106 },
+    "headers": ["algorithm"],
+    "unimplemented": True,
+  }, {
+    "name": "__cpp_lib_ranges_zip",
+    "values": { "c++2b": 202110 },
+    "headers": ["ranges", "tuple", "utility"],
+    "unimplemented": True,
+  }, {
     "name": "__cpp_lib_raw_memory_algorithms",
     "values": { "c++17": 201606 },
     "headers": ["memory"],
   }, {
     "name": "__cpp_lib_remove_cvref",
     "values": { "c++20": 201711 },
     "headers": ["type_traits"],
   }, {
feature_test_macros = [ add_version_header(x) for x in [
     "values": { "c++20": 201907 },
     "headers": ["source_location"],
     "unimplemented": True,
   }, {
     "name": "__cpp_lib_span",
     "values": { "c++20": 202002 },
     "headers": ["span"],
   }, {
+    "name": "__cpp_lib_spanstream",
+    "values": { "c++2b": 202106 },
+    "headers": ["spanstream"],
+    "unimplemented": True,
+  }, {
     "name": "__cpp_lib_ssize",
     "values": { "c++20": 201902 },
     "headers": ["iterator"],
   }, {
     "name": "__cpp_lib_stacktrace",
     "values": { "c++2b": 202011 },
     "headers": ["stacktrace"],
     "unimplemented": True,
feature_test_macros = [ add_version_header(x) for x in [
     "name": "__cpp_lib_tuple_element_t",
     "values": { "c++14": 201402 },
     "headers": ["tuple"],
   }, {
     "name": "__cpp_lib_tuples_by_type",
     "values": { "c++14": 201304 },
     "headers": ["tuple", "utility"],
   }, {
+    "name": "__cpp_lib_type_identity",
+    "values": { "c++20": 201806 },
+    "headers": ["type_traits"],
+  }, {
     "name": "__cpp_lib_type_trait_variable_templates",
     "values": { "c++17": 201510 },
     "headers": ["type_traits"],
   }, {
     "name": "__cpp_lib_uncaught_exceptions",
     "values": { "c++17": 201411 },
     "headers": ["exception"],
   }, {