diff --git a/include/boost/config/detail/suffix.hpp b/include/boost/config/detail/suffix.hpp
index 870d2e6b..c11a4140 100644
--- a/include/boost/config/detail/suffix.hpp
+++ b/include/boost/config/detail/suffix.hpp
@@ -1135,9 +1135,14 @@ namespace std{ using ::type_info; }
 #endif
 #endif
 #endif
+//
+// Define the std level that the compiler claims to support:
+//
+#ifndef BOOST_CXX_VERSION
+#  define BOOST_CXX_VERSION __cplusplus
+#endif
 
-#if !defined(_YVALS) && !defined(_CPPLIB_VER)  // msvc std lib already configured
-#if (!defined(__has_include) || (__cplusplus < 201704))
+#if (!defined(__has_include) || (BOOST_CXX_VERSION < 201704))
 #  define BOOST_NO_CXX20_HDR_BARRIER
 #  define BOOST_NO_CXX20_HDR_FORMAT
 #  define BOOST_NO_CXX20_HDR_SOURCE_LOCATION
@@ -1153,50 +1158,49 @@ namespace std{ using ::type_info; }
 #  define BOOST_NO_CXX20_HDR_COROUTINE
 #  define BOOST_NO_CXX20_HDR_SEMAPHORE
 #else
-#if !__has_include(<barrier>)
+#if (!__has_include(<barrier>) || !defined(__cpp_lib_barrier) || (__cpp_lib_barrier < 201907L)) && !defined(BOOST_NO_CXX20_HDR_BARRIER)
 #  define BOOST_NO_CXX20_HDR_BARRIER
 #endif
-#if !__has_include(<format>)
+#if (!__has_include(<format>) || !defined(__cpp_lib_format) || (__cpp_lib_format < 201907L)) && !defined(BOOST_NO_CXX20_HDR_FORMAT)
 #  define BOOST_NO_CXX20_HDR_FORMAT
 #endif
-#if !__has_include(<source_location>)
+#if (!__has_include(<source_location>) || !defined(__cpp_lib_source_location) || (__cpp_lib_source_location < 201907L)) && !defined(BOOST_NO_CXX20_HDR_SOURCE_LOCATION)
 #  define BOOST_NO_CXX20_HDR_SOURCE_LOCATION
 #endif
-#if !__has_include(<bit>)
+#if (!__has_include(<bit>) || !defined(__cpp_lib_bit_cast) || (__cpp_lib_bit_cast < 201806L) || !defined(__cpp_lib_bitops) || (__cpp_lib_bitops < 201907L) || !defined(__cpp_lib_endian) || (__cpp_lib_endian < 201907L)) && !defined(BOOST_NO_CXX20_HDR_BIT)
 #  define BOOST_NO_CXX20_HDR_BIT
 #endif
-#if !__has_include(<latch>)
+#if (!__has_include(<latch>) || !defined(__cpp_lib_latch) || (__cpp_lib_latch < 201907L)) && !defined(BOOST_NO_CXX20_HDR_LATCH)
 #  define BOOST_NO_CXX20_HDR_LATCH
 #endif
-#if !__has_include(<span>)
+#if (!__has_include(<span>) || !defined(__cpp_lib_span) || (__cpp_lib_span < 202002L)) && !defined(BOOST_NO_CXX20_HDR_SPAN)
 #  define BOOST_NO_CXX20_HDR_SPAN
 #endif
-#if !__has_include(<compare>)
+#if (!__has_include(<compare>) || !defined(__cpp_lib_three_way_comparison) || (__cpp_lib_three_way_comparison < 201907L)) && !defined(BOOST_NO_CXX20_HDR_COMPARE)
 #  define BOOST_NO_CXX20_HDR_COMPARE
 #endif
-#if !__has_include(<numbers>)
+#if (!__has_include(<numbers>) || !defined(__cpp_lib_math_constants) || (__cpp_lib_math_constants < 201907L)) && !defined(BOOST_NO_CXX20_HDR_NUMBERS)
 #  define BOOST_NO_CXX20_HDR_NUMBERS
 #endif
-#if !__has_include(<stop_token>)
+#if (!__has_include(<stop_token>) || !defined(__cpp_lib_jthread) || (__cpp_lib_jthread < 201911L)) && !defined(BOOST_NO_CXX20_HDR_STOP_TOKEN)
 #  define BOOST_NO_CXX20_HDR_STOP_TOKEN
 #endif
-#if !__has_include(<concepts>)
+#if (!__has_include(<concepts>) || !defined(__cpp_lib_concepts) || (__cpp_lib_concepts < 202002L)) && !defined(_YVALS) && !defined(_CPPLIB_VER) && !defined(BOOST_NO_CXX20_HDR_CONCEPTS)
 #  define BOOST_NO_CXX20_HDR_CONCEPTS
 #endif
-#if !__has_include(<ranges>)
+#if (!__has_include(<ranges>) || !defined(__cpp_lib_ranges) || (__cpp_lib_ranges < 201911L)) && !defined(BOOST_NO_CXX20_HDR_RANGES)
 #  define BOOST_NO_CXX20_HDR_RANGES
 #endif
-#if !__has_include(<syncstream>)
+#if (!__has_include(<syncstream>) || !defined(__cpp_lib_syncbuf) || (__cpp_lib_syncbuf < 201803L)) && !defined(BOOST_NO_CXX20_HDR_SYNCSTREAM)
 #  define BOOST_NO_CXX20_HDR_SYNCSTREAM
 #endif
-#if !__has_include(<coroutine>)
+#if (!__has_include(<coroutine>) || !defined(__cpp_lib_coroutine) || (__cpp_lib_coroutine < 201902L)) && !defined(BOOST_NO_CXX20_HDR_COROUTINE)
 #  define BOOST_NO_CXX20_HDR_COROUTINE
 #endif
-#if !__has_include(<semaphore>)
+#if (!__has_include(<semaphore>) || !defined(__cpp_lib_semaphore) || (__cpp_lib_semaphore < 201907L)) && !defined(BOOST_NO_CXX20_HDR_SEMAPHORE)
 #  define BOOST_NO_CXX20_HDR_SEMAPHORE
 #endif
 #endif
-#endif
 
 #ifdef __has_include
 #if !__has_include(<version>)
@@ -1211,13 +1215,6 @@ namespace std{ using ::type_info; }
 //
 #include <boost/config/detail/cxx_composite.hpp>
 
-//
-// Define the std level that the compiler claims to support:
-//
-#ifndef BOOST_CXX_VERSION
-#  define BOOST_CXX_VERSION __cplusplus
-#endif
-
 //
 // Finish off with checks for macros that are depricated / no longer supported,
 // if any of these are set then it's very likely that much of Boost will no
diff --git a/include/boost/config/stdlib/dinkumware.hpp b/include/boost/config/stdlib/dinkumware.hpp
index a98aaf79..8feccc65 100644
--- a/include/boost/config/stdlib/dinkumware.hpp
+++ b/include/boost/config/stdlib/dinkumware.hpp
@@ -194,35 +194,10 @@
 #  define BOOST_NO_CXX17_STD_INVOKE
 #endif
 
-// C++20 features
+// C++20 features which aren't configured in suffix.hpp correctly:
 #if !defined(_MSVC_STL_UPDATE) || (_MSVC_STL_UPDATE < 202008L) || !defined(_HAS_CXX20) || (_HAS_CXX20 == 0)
-#  define BOOST_NO_CXX20_HDR_BARRIER
-#  define BOOST_NO_CXX20_HDR_BIT
-#  define BOOST_NO_CXX20_HDR_LATCH
-#  define BOOST_NO_CXX20_HDR_SPAN
-#  define BOOST_NO_CXX20_HDR_COMPARE
-#  define BOOST_NO_CXX20_HDR_NUMBERS
 #  define BOOST_NO_CXX20_HDR_CONCEPTS
-#  define BOOST_NO_CXX20_HDR_COROUTINE
-#  define BOOST_NO_CXX20_HDR_SEMAPHORE
 #endif
-#if !defined(_MSVC_STL_UPDATE) || (_MSVC_STL_UPDATE < 202011L) || !defined(_HAS_CXX20) || (_HAS_CXX20 == 0)
-#  define BOOST_NO_CXX20_HDR_STOP_TOKEN
-#endif
-// C++20 features not yet implemented:
-#  define BOOST_NO_CXX20_HDR_FORMAT
-#if !defined(_MSVC_STL_UPDATE) || (_MSVC_STL_UPDATE < 202108L) || !defined(_HAS_CXX20) || (_HAS_CXX20 == 0)
-#  define BOOST_NO_CXX20_HDR_SOURCE_LOCATION
-#  define BOOST_NO_CXX20_HDR_SYNCSTREAM
-#endif
-#if !defined(BOOST_NO_CXX20_HDR_COROUTINE) && !defined(__cpp_lib_coroutine)
-#  define BOOST_NO_CXX20_HDR_COROUTINE
-#endif
-#if !defined(BOOST_NO_CXX20_HDR_SOURCE_LOCATION) && !defined(__cpp_consteval)
-#  define BOOST_NO_CXX20_HDR_SOURCE_LOCATION
-#endif
-// Incomplete:
-#  define BOOST_NO_CXX20_HDR_RANGES
 
 #if !(!defined(_CPPLIB_VER) || (_CPPLIB_VER < 650) || !defined(BOOST_MSVC) || (BOOST_MSVC < 1912) || !defined(_HAS_CXX17) || (_HAS_CXX17 == 0))
 // Deprecated std::iterator:
diff --git a/include/boost/config/stdlib/libcpp.hpp b/include/boost/config/stdlib/libcpp.hpp
index eeea2305..fc1d5bb4 100644
--- a/include/boost/config/stdlib/libcpp.hpp
+++ b/include/boost/config/stdlib/libcpp.hpp
@@ -115,53 +115,7 @@
 #define BOOST_NO_CXX17_STD_INVOKE
 #endif
 
-#if !defined(__cpp_lib_bit_cast) || (__cpp_lib_bit_cast < 201806L) || !defined(__cpp_lib_bitops) || (__cpp_lib_bitops < 201907L) || !defined(__cpp_lib_endian) || (__cpp_lib_endian < 201907L)
-#  define BOOST_NO_CXX20_HDR_BIT
-#endif
-#if !defined(__cpp_lib_three_way_comparison) || (__cpp_lib_three_way_comparison < 201907L)
-#  define BOOST_NO_CXX20_HDR_COMPARE
-#endif
-#if !defined(__cpp_lib_ranges) || (__cpp_lib_ranges < 201911L)
-#  define BOOST_NO_CXX20_HDR_RANGES
-#endif
-#if !defined(__cpp_lib_barrier) || (__cpp_lib_barrier < 201907L)
-#  define BOOST_NO_CXX20_HDR_BARRIER
-#endif
-#if !defined(__cpp_lib_format) || (__cpp_lib_format < 201907L)
-#  define BOOST_NO_CXX20_HDR_FORMAT
-#endif
-#if !defined(__cpp_lib_source_location) || (__cpp_lib_source_location < 201907L)
-#  define BOOST_NO_CXX20_HDR_SOURCE_LOCATION
-#endif
-#if !defined(__cpp_lib_latch) || (__cpp_lib_latch < 201907L)
-#  define BOOST_NO_CXX20_HDR_LATCH
-#endif
-#if !defined(__cpp_lib_span) || (__cpp_lib_span < 202002L)
-#  define BOOST_NO_CXX20_HDR_SPAN
-#endif
-#if !defined(__cpp_lib_math_constants) || (__cpp_lib_math_constants < 201907L)
-#  define BOOST_NO_CXX20_HDR_NUMBERS
-#endif
-#if !defined(__cpp_lib_jthread) || (__cpp_lib_jthread < 201911L)
-#  define BOOST_NO_CXX20_HDR_STOP_TOKEN
-#endif
-#if !defined(__cpp_lib_concepts) || (__cpp_lib_concepts < 202002L)
-#  define BOOST_NO_CXX20_HDR_STOP_CONCEPTS
-#endif
-#if !defined(__cpp_lib_syncbuf) || (__cpp_lib_syncbuf < 201803L)
-#  define BOOST_NO_CXX20_HDR_SYNCSTREAM
-#endif
-#if !defined(__cpp_lib_coroutine) || (__cpp_lib_coroutine < 201902L)
-#  define BOOST_NO_CXX20_HDR_COROUTINE
-#endif
-#if !defined(__cpp_lib_semaphore) || (__cpp_lib_semaphore < 201907L)
-#  define BOOST_NO_CXX20_HDR_SEMAPHORE
-#endif
-#if !defined(__cpp_lib_concepts) || (__cpp_lib_concepts < 202002L)
-#  define BOOST_NO_CXX20_HDR_CONCEPTS
-#endif
-
-#if(_LIBCPP_VERSION < 9000) && !defined(BOOST_NO_CXX20_HDR_SPAN)
+#if(_LIBCPP_VERSION < 9000)
 // as_writable_bytes is missing.
 #  define BOOST_NO_CXX20_HDR_SPAN
 #endif