diff --git a/libstdc++-v3/include/bits/ptr_traits.h b/libstdc++-v3/include/bits/ptr_traits.h
index dc42a743c96..f6cc6b65f93 100644
--- a/libstdc++-v3/include/bits/ptr_traits.h
+++ b/libstdc++-v3/include/bits/ptr_traits.h
@@ -34,12 +34,15 @@
 
 #include <bits/move.h>
 
+/* Duplicate definition with unique_ptr.h.  */
+#if __cplusplus > 202002L && defined(__cpp_constexpr_dynamic_alloc)
+# define __cpp_lib_constexpr_memory 202202L
+#elif __cplusplus > 201703L
+# include <concepts>
+# define __cpp_lib_constexpr_memory 201811L
+#endif
+
 #if __cplusplus > 201703L
-#include <concepts>
-# ifndef __cpp_lib_constexpr_memory
-// Defined to a newer value in bits/unique_ptr.h for C++23
-#  define __cpp_lib_constexpr_memory 201811L
-# endif
 namespace __gnu_debug { struct _Safe_iterator_base; }
 #endif
 
diff --git a/libstdc++-v3/include/bits/unique_ptr.h b/libstdc++-v3/include/bits/unique_ptr.h
index c8daff41865..f0c6d2383b4 100644
--- a/libstdc++-v3/include/bits/unique_ptr.h
+++ b/libstdc++-v3/include/bits/unique_ptr.h
@@ -43,12 +43,11 @@
 # endif
 #endif
 
-#if __cplusplus > 202002L && __cpp_constexpr_dynamic_alloc
-# if __cpp_lib_constexpr_memory < 202202L
-// Defined with older value in bits/ptr_traits.h for C++20
-#  undef __cpp_lib_constexpr_memory
-#  define __cpp_lib_constexpr_memory 202202L
-# endif
+/* Duplicate definition with ptr_traits.h.  */
+#if __cplusplus > 202002L && defined(__cpp_constexpr_dynamic_alloc)
+# define __cpp_lib_constexpr_memory 202202L
+#elif __cplusplus > 201703L
+# define __cpp_lib_constexpr_memory 201811L
 #endif
 
 namespace std _GLIBCXX_VISIBILITY(default)
diff --git a/libstdc++-v3/include/std/memory b/libstdc++-v3/include/std/memory
index 341f9857730..85c36d67ee1 100644
--- a/libstdc++-v3/include/std/memory
+++ b/libstdc++-v3/include/std/memory
@@ -91,6 +91,12 @@
 #  include <bits/uses_allocator_args.h>
 #endif
 
+/* As a hack, we declare __cpp_lib_atomic_value_initialization here even though
+   we don't include the bit that actually declares it, for consistency.  */
+#if !defined(__cpp_lib_atomic_value_initialization) && __cplusplus >= 202002L
+# define __cpp_lib_atomic_value_initialization 201911L
+#endif
+
 #if __cplusplus >= 201103L && __cplusplus <= 202002L && _GLIBCXX_HOSTED
 namespace std _GLIBCXX_VISIBILITY(default)
 {
diff --git a/libstdc++-v3/include/std/version b/libstdc++-v3/include/std/version
index a19c39c6cdd..0239fcea813 100644
--- a/libstdc++-v3/include/std/version
+++ b/libstdc++-v3/include/std/version
@@ -85,6 +85,12 @@
 #define __cpp_lib_transparent_operators 201510L
 #define __cpp_lib_tuple_element_t 201402L
 #define __cpp_lib_tuples_by_type 201304L
+#define __cpp_lib_robust_nonmodifying_seq_ops 201304L
+
+#if _GLIBCXX_FLOAT_IS_IEEE_BINARY32 && _GLIBCXX_DOUBLE_IS_IEEE_BINARY64 \
+    && __SIZE_WIDTH__ >= 32
+# define __cpp_lib_to_chars 201611L
+#endif
 
 #if _GLIBCXX_HOSTED
 # define __cpp_lib_chrono_udls 201304L
@@ -92,7 +98,6 @@
 # define __cpp_lib_generic_associative_lookup 201304L
 # define __cpp_lib_make_unique 201304L
 # define __cpp_lib_quoted_string_io 201304L
-# define __cpp_lib_robust_nonmodifying_seq_ops 201304L
 # ifdef _GLIBCXX_HAS_GTHREADS
 #  define __cpp_lib_shared_timed_mutex 201402L
 # endif
@@ -136,13 +141,13 @@
 # define __cpp_lib_variant 202102L
 #endif
 #define __cpp_lib_void_t 201411L
-
-#if _GLIBCXX_HOSTED
+#define __cpp_lib_gcd 201606L
+#define __cpp_lib_gcd_lcm 201606L
+#define __cpp_lib_raw_memory_algorithms 201606L
 #if __cplusplus == 201703L // N.B. updated value in C++20
 # define __cpp_lib_array_constexpr 201803L
 #endif
-#define __cpp_lib_boyer_moore_searcher 201603L
-#define __cpp_lib_chrono 201611L
+#define __cpp_lib_nonmember_container_access 201411L
 #define __cpp_lib_clamp 201603L
 #if __cplusplus == 201703L // N.B. updated value in C++20
 # if _GLIBCXX_HAVE_IS_CONSTANT_EVALUATED
@@ -150,13 +155,16 @@
 #  define __cpp_lib_constexpr_string 201611L
 # endif
 #endif
+#define __cpp_lib_sample 201603L
+#define __cpp_lib_lcm 201606L
+
+#if _GLIBCXX_HOSTED
+#define __cpp_lib_boyer_moore_searcher 201603L
+#define __cpp_lib_chrono 201611L
 #define __cpp_lib_enable_shared_from_this 201603L
 #define __cpp_lib_execution 201902L // FIXME: should be 201603L
 #define __cpp_lib_filesystem 201703L
-#define __cpp_lib_gcd 201606L
-#define __cpp_lib_gcd_lcm 201606L
 #define __cpp_lib_hypot 201603L
-#define __cpp_lib_lcm 201606L
 #define __cpp_lib_map_try_emplace 201411L
 #define __cpp_lib_math_special_functions 201603L
 #ifdef _GLIBCXX_HAS_GTHREADS
@@ -165,20 +173,13 @@
 # define __cpp_lib_memory_resource 1
 #endif
 #define __cpp_lib_node_extract 201606L
-#define __cpp_lib_nonmember_container_access 201411L
 #define __cpp_lib_parallel_algorithm 201603L
-#define __cpp_lib_raw_memory_algorithms 201606L
-#define __cpp_lib_sample 201603L
 #ifdef _GLIBCXX_HAS_GTHREADS
 # define __cpp_lib_scoped_lock 201703L
 # define __cpp_lib_shared_mutex 201505L
 #endif
 #define __cpp_lib_shared_ptr_weak_type 201606L
 #define __cpp_lib_string_view 201803L
-#if _GLIBCXX_FLOAT_IS_IEEE_BINARY32 && _GLIBCXX_DOUBLE_IS_IEEE_BINARY64 \
-    && __SIZE_WIDTH__ >= 32
-# define __cpp_lib_to_chars 201611L
-#endif
 #define __cpp_lib_unordered_map_try_emplace 201411L
 #endif
 
@@ -224,7 +225,9 @@
 #if __cpp_lib_concepts
 # define __cpp_lib_make_obj_using_allocator 201811L
 #endif
-#define __cpp_lib_optional 202106L
+#if __cplusplus <= 202002L // N.B. updated value in C++23
+# define __cpp_lib_optional 202106L
+#endif
 #define __cpp_lib_remove_cvref 201711L
 #if __has_builtin(__builtin_source_location)
 # define __cpp_lib_source_location 201907L
@@ -243,9 +246,27 @@
 #if __cpp_concepts >= 202002L && __cpp_constexpr >= 201811L
 # define __cpp_lib_variant 202106L
 #endif
-
-#if _GLIBCXX_HOSTED
 #define __cpp_lib_array_constexpr 201811L
+#define __cpp_lib_constexpr_iterator 201811L
+#ifdef __cpp_lib_is_constant_evaluated
+# define __cpp_lib_constexpr_char_traits 201811L
+#endif
+#define __cpp_lib_interpolate 201902L
+#define __cpp_lib_constexpr_utility 201811L
+#define __cpp_lib_shift 201806L
+#if __cpp_lib_concepts
+# define __cpp_lib_move_iterator_concept 202207L
+# define __cpp_lib_ranges 202110L
+#endif
+#define __cpp_lib_constexpr_numeric 201911L
+#define __cpp_lib_constexpr_functional 201907L
+#define __cpp_lib_constexpr_algorithms 201806L
+#define __cpp_lib_constexpr_tuple 201811L
+#if __cplusplus <= 202002L // N.B. updated value in C++23
+# define __cpp_lib_constexpr_memory 201811L
+#endif // C++20
+
+#if _GLIBCXX_HOSTED
 #define __cpp_lib_atomic_shared_ptr 201711L
 #if defined _GLIBCXX_HAS_GTHREADS || defined _GLIBCXX_HAVE_LINUX_FUTEX
 # define __cpp_lib_atomic_wait 201907L
@@ -256,16 +277,9 @@
 // #undef __cpp_lib_chrono
 // #define __cpp_lib_chrono 201907L
 // FIXME: #define __cpp_lib_execution 201902L
-#define __cpp_lib_constexpr_algorithms 201806L
-#ifdef __cpp_lib_is_constant_evaluated
-# define __cpp_lib_constexpr_char_traits 201811L
-#endif
 #define __cpp_lib_constexpr_complex 201711L
 #define __cpp_lib_constexpr_dynamic_alloc 201907L
-#define __cpp_lib_constexpr_functional 201907L
-#define __cpp_lib_constexpr_iterator 201811L
-#define __cpp_lib_constexpr_memory 201811L
-#define __cpp_lib_constexpr_numeric 201911L
+#define __cpp_lib_constexpr_tuple 201811L
 #ifdef __cpp_lib_is_constant_evaluated
 # if _GLIBCXX_USE_CXX11_ABI
 #  define __cpp_lib_constexpr_string 201907L
@@ -273,13 +287,10 @@
 #  define __cpp_lib_constexpr_string 201811L
 # endif
 #endif
-#define __cpp_lib_constexpr_tuple 201811L
-#define __cpp_lib_constexpr_utility 201811L
 #define __cpp_lib_constexpr_vector 201907L
 #define __cpp_lib_erase_if 202002L
 #define __cpp_lib_format 202106L
 #define __cpp_lib_generic_unordered_lookup 201811L
-#define __cpp_lib_interpolate 201902L
 #ifdef _GLIBCXX_HAS_GTHREADS
 # define __cpp_lib_jthread 201911L
 #endif
@@ -288,15 +299,10 @@
 #endif
 #define __cpp_lib_list_remove_return_type 201806L
 #define __cpp_lib_polymorphic_allocator 201902L
-#if __cpp_lib_concepts
-# define __cpp_lib_ranges 202110L
-# define __cpp_lib_move_iterator_concept 202207L
-#endif
 #if __cpp_lib_atomic_wait || _GLIBCXX_HAVE_POSIX_SEMAPHORE
 # define __cpp_lib_semaphore 201907L
 #endif
 #define __cpp_lib_shared_ptr_arrays 201707L
-#define __cpp_lib_shift 201806L
 #define __cpp_lib_smart_ptr_for_overwrite 202002L
 # if _GLIBCXX_USE_CXX11_ABI
 // Only supported with cxx11-abi
@@ -330,14 +336,17 @@
 #define __cpp_lib_ranges_stride 202207L
 #define __cpp_lib_ranges_cartesian_product 202207L
 #define __cpp_lib_ranges_as_rvalue 202207L
-
-#if _GLIBCXX_HOSTED
-#define __cpp_lib_adaptor_iterator_pair_constructor 202106L
 #if __cpp_constexpr_dynamic_alloc
-# define __cpp_lib_constexpr_bitset 202202L
+# if _GLIBCXX_HOSTED
+#  define __cpp_lib_constexpr_bitset 202202L
+# endif
 # undef __cpp_lib_constexpr_memory
 # define __cpp_lib_constexpr_memory 202202L
 #endif
+#define __cpp_lib_stdatomic_h 202011L
+
+#if _GLIBCXX_HOSTED
+#define __cpp_lib_adaptor_iterator_pair_constructor 202106L
 #define __cpp_lib_ios_noreplace 202207L
 #define __cpp_lib_move_only_function 202110L
 #if __cpp_lib_span
