diff --git a/include/boost/locale/boundary/boundary_point.hpp b/include/boost/locale/boundary/boundary_point.hpp
index 370dd5f..0743347 100644
--- a/include/boost/locale/boundary/boundary_point.hpp
+++ b/include/boost/locale/boundary/boundary_point.hpp
@@ -100,7 +100,7 @@ namespace boost { namespace locale { namespace boundary {
 
     typedef boundary_point<std::string::const_iterator> sboundary_point;   ///< convenience typedef
     typedef boundary_point<std::wstring::const_iterator> wsboundary_point; ///< convenience typedef
-#ifndef BOOST_LOCALE_NO_CXX20_STRING8
+#ifdef __cpp_lib_char8_t
     typedef boundary_point<std::u8string::const_iterator> u8sboundary_point; ///< convenience typedef
 #endif
 #ifdef BOOST_LOCALE_ENABLE_CHAR16_T
diff --git a/include/boost/locale/boundary/index.hpp b/include/boost/locale/boundary/index.hpp
index 92b7613..249ef87 100644
--- a/include/boost/locale/boundary/index.hpp
+++ b/include/boost/locale/boundary/index.hpp
@@ -868,7 +868,7 @@ namespace boost { namespace locale { namespace boundary {
 
     typedef segment_index<std::string::const_iterator> ssegment_index;   ///< convenience typedef
     typedef segment_index<std::wstring::const_iterator> wssegment_index; ///< convenience typedef
-#ifndef BOOST_LOCALE_NO_CXX20_STRING8
+#ifdef __cpp_lib_char8_t
     typedef segment_index<std::u8string::const_iterator> u8ssegment_index; ///< convenience typedef
 #endif
 #ifdef BOOST_LOCALE_ENABLE_CHAR16_T
@@ -892,7 +892,7 @@ namespace boost { namespace locale { namespace boundary {
 
     typedef boundary_point_index<std::string::const_iterator> sboundary_point_index;   ///< convenience typedef
     typedef boundary_point_index<std::wstring::const_iterator> wsboundary_point_index; ///< convenience typedef
-#ifndef BOOST_LOCALE_NO_CXX20_STRING8
+#ifdef __cpp_lib_char8_t
     typedef boundary_point_index<std::u8string::const_iterator> u8sboundary_point_index; ///< convenience typedef
 #endif
 #ifdef BOOST_LOCALE_ENABLE_CHAR16_T
diff --git a/include/boost/locale/boundary/segment.hpp b/include/boost/locale/boundary/segment.hpp
index 24e129d..84243ab 100644
--- a/include/boost/locale/boundary/segment.hpp
+++ b/include/boost/locale/boundary/segment.hpp
@@ -340,7 +340,7 @@ namespace boost { namespace locale { namespace boundary {
 
     typedef segment<std::string::const_iterator> ssegment;   ///< convenience typedef
     typedef segment<std::wstring::const_iterator> wssegment; ///< convenience typedef
-#ifndef BOOST_LOCALE_NO_CXX20_STRING8
+#ifdef __cpp_lib_char8_t
     typedef segment<std::u8string::const_iterator> u8ssegment; ///< convenience typedef
 #endif
 #ifdef BOOST_LOCALE_ENABLE_CHAR16_T
diff --git a/include/boost/locale/config.hpp b/include/boost/locale/config.hpp
index 1c69c92..2064810 100644
--- a/include/boost/locale/config.hpp
+++ b/include/boost/locale/config.hpp
@@ -89,11 +89,6 @@
 #    define BOOST_LOCALE_NO_SANITIZE(what)
 #endif
 
-#if !defined(__cpp_lib_char8_t) || BOOST_WORKAROUND(BOOST_CLANG_VERSION, < 150000)
-// No std::basic_string<char8_t> or bug in Clang: https://github.com/llvm/llvm-project/issues/55560
-#    define BOOST_LOCALE_NO_CXX20_STRING8
-#endif
-
 /// \endcond
 
 #endif // boost/locale/config.hpp
diff --git a/include/boost/locale/format.hpp b/include/boost/locale/format.hpp
index 58a9a0f..68020a4 100644
--- a/include/boost/locale/format.hpp
+++ b/include/boost/locale/format.hpp
@@ -418,7 +418,7 @@ namespace boost { namespace locale {
     typedef basic_format<char> format;
     /// Definition of wchar_t based format
     typedef basic_format<wchar_t> wformat;
-#ifndef BOOST_LOCALE_NO_CXX20_STRING8
+#ifdef __cpp_lib_char8_t
     /// Definition of char8_t based format
     typedef basic_format<char8_t> u8format;
 #endif
diff --git a/include/boost/locale/message.hpp b/include/boost/locale/message.hpp
index 88a4aef..fafff38 100644
--- a/include/boost/locale/message.hpp
+++ b/include/boost/locale/message.hpp
@@ -341,7 +341,7 @@ namespace boost { namespace locale {
     typedef basic_message<char> message;
     /// Convenience typedef for wchar_t
     typedef basic_message<wchar_t> wmessage;
-#ifndef BOOST_LOCALE_NO_CXX20_STRING8
+#ifdef __cpp_lib_char8_t
     /// Convenience typedef for char8_t
     typedef basic_message<char8_t> u8message;
 #endif
diff --git a/src/encoding/codepage.cpp b/src/encoding/codepage.cpp
index 0f052b8..814a803 100644
--- a/src/encoding/codepage.cpp
+++ b/src/encoding/codepage.cpp
@@ -224,7 +224,7 @@ namespace boost { namespace locale { namespace conv {
     BOOST_LOCALE_INSTANTIATE(char);
     BOOST_LOCALE_INSTANTIATE_NO_CHAR(wchar_t);
 
-#ifndef BOOST_LOCALE_NO_CXX20_STRING8
+#ifdef __cpp_lib_char8_t
     BOOST_LOCALE_INSTANTIATE_NO_CHAR(char8_t);
 #endif
 
diff --git a/src/icu/conversion.cpp b/src/icu/conversion.cpp
index 130a0d4..a7fddb4 100644
--- a/src/icu/conversion.cpp
+++ b/src/icu/conversion.cpp
@@ -198,7 +198,7 @@ namespace boost { namespace locale { namespace impl_icu {
                     return std::locale(in, new utf8_converter_impl<char>(cd));
                 return std::locale(in, new converter_impl<char>(cd));
             case char_facet_t::wchar_f: return std::locale(in, new converter_impl<wchar_t>(cd));
-#ifndef BOOST_LOCALE_NO_CXX20_STRING8
+#ifdef __cpp_lib_char8_t
             case char_facet_t::char8_f: return std::locale(in, new utf8_converter_impl<char8_t>(cd));
 #elif defined(__cpp_char8_t)
             case char_facet_t::char8_f: break;
diff --git a/src/posix/converter.cpp b/src/posix/converter.cpp
index 38a4bb6..13477aa 100644
--- a/src/posix/converter.cpp
+++ b/src/posix/converter.cpp
@@ -125,7 +125,7 @@ namespace boost { namespace locale { namespace impl_posix {
                 return std::locale(in, new std_converter<char>(std::move(lc)));
             }
             case char_facet_t::wchar_f: return std::locale(in, new std_converter<wchar_t>(std::move(lc)));
-#ifndef BOOST_LOCALE_NO_CXX20_STRING8
+#ifdef __cpp_lib_char8_t
             case char_facet_t::char8_f: return std::locale(in, new utf8_converter<char8_t>(std::move(lc)));
 #elif defined(__cpp_char8_t)
             case char_facet_t::char8_f: break;
diff --git a/src/shared/message.cpp b/src/shared/message.cpp
index 88cee09..70eafd2 100644
--- a/src/shared/message.cpp
+++ b/src/shared/message.cpp
@@ -620,7 +620,7 @@ namespace boost { namespace locale { namespace detail {
             case char_facet_t::nochar: break;
             case char_facet_t::char_f: return std::locale(in, gnu_gettext::create_messages_facet<char>(minf));
             case char_facet_t::wchar_f: return std::locale(in, gnu_gettext::create_messages_facet<wchar_t>(minf));
-#ifndef BOOST_LOCALE_NO_CXX20_STRING8
+#ifdef __cpp_lib_char8_t
             case char_facet_t::char8_f: return std::locale(in, gnu_gettext::create_messages_facet<char8_t>(minf));
 #elif defined(__cpp_char8_t)
             case char_facet_t::char8_f: break;
diff --git a/src/std/converter.cpp b/src/std/converter.cpp
index fcfb7df..ec60a58 100644
--- a/src/std/converter.cpp
+++ b/src/std/converter.cpp
@@ -104,7 +104,7 @@ namespace boost { namespace locale { namespace impl_std {
                 else
                     return std::locale(in, new std_converter<char>(locale_name));
             case char_facet_t::wchar_f: return std::locale(in, new std_converter<wchar_t>(locale_name));
-#ifndef BOOST_LOCALE_NO_CXX20_STRING8
+#ifdef __cpp_lib_char8_t
             case char_facet_t::char8_f: return std::locale(in, new utf8_converter<char8_t>(locale_name));
 #elif defined(__cpp_char8_t)
             case char_facet_t::char8_f: break;
diff --git a/src/util/foreach_char.hpp b/src/util/foreach_char.hpp
index 37328e1..1c0dc35 100644
--- a/src/util/foreach_char.hpp
+++ b/src/util/foreach_char.hpp
@@ -9,7 +9,7 @@
 
 #include <boost/locale/config.hpp>
 
-#ifndef BOOST_LOCALE_NO_CXX20_STRING8
+#ifdef __cpp_lib_char8_t
 #    define BOOST_LOCALE_FOREACH_CHAR_I_CHAR8_T(F) F(char8_t)
 #    define BOOST_LOCALE_FOREACH_CHAR_I2_CHAR8_T(F) F(char8_t)
 #elif defined(__cpp_char8_t)
diff --git a/src/win32/converter.cpp b/src/win32/converter.cpp
index 455fef6..fe168df 100644
--- a/src/win32/converter.cpp
+++ b/src/win32/converter.cpp
@@ -62,7 +62,7 @@ namespace boost { namespace locale { namespace impl_win {
             case char_facet_t::nochar: break;
             case char_facet_t::char_f: return std::locale(in, new utf8_converter<char>(lc));
             case char_facet_t::wchar_f: return std::locale(in, new wide_converter(lc));
-#ifndef BOOST_LOCALE_NO_CXX20_STRING8
+#ifdef __cpp_lib_char8_t
             case char_facet_t::char8_f: return std::locale(in, new utf8_converter<char8_t>(lc));
 #elif defined(__cpp_char8_t)
             case char_facet_t::char8_f: break;
diff --git a/test/boostLocale/test/tools.hpp b/test/boostLocale/test/tools.hpp
index 7e9a045..6537aa5 100644
--- a/test/boostLocale/test/tools.hpp
+++ b/test/boostLocale/test/tools.hpp
@@ -113,7 +113,7 @@ std::basic_string<Char> to(const std::string& utf8)
     return out;
 }
 
-#ifndef BOOST_LOCALE_NO_CXX20_STRING8
+#ifdef __cpp_lib_char8_t
 template<>
 std::basic_string<char8_t> to(const std::string& utf8)
 {
diff --git a/test/show_config.cpp b/test/show_config.cpp
index 226ec1c..e2dd854 100644
--- a/test/show_config.cpp
+++ b/test/show_config.cpp
@@ -65,7 +65,7 @@ void test_main(int /*argc*/, char** /*argv*/)
     std::cout << "no\n";
 #endif
     std::cout << "- std::basic_string<char8_t>: ";
-#ifndef BOOST_LOCALE_NO_CXX20_STRING8
+#ifdef __cpp_lib_char8_t
     std::cout << "yes\n";
 #elif defined(__cpp_lib_char8_t)
     std::cout << "partial\n";
diff --git a/test/test_boundary.cpp b/test/test_boundary.cpp
index 7a2715a..64b1b76 100644
--- a/test/test_boundary.cpp
+++ b/test/test_boundary.cpp
@@ -310,7 +310,7 @@ void test_boundaries(std::string* all, int* first, int* second, lb::boundary_typ
     run_word<char>(all, first, second, nullptr, nullptr, nullptr, g("he_IL.cp1255"), t);
     std::cout << " wchar_t" << std::endl;
     run_word<wchar_t>(all, first, second, nullptr, nullptr, nullptr, g("he_IL.UTF-8"), t);
-#ifndef BOOST_LOCALE_NO_CXX20_STRING8
+#ifdef __cpp_lib_char8_t
     std::cout << " char8_t" << std::endl;
     run_word<char8_t>(all, first, second, nullptr, nullptr, nullptr, g("he_IL.UTF-8"), t);
 #endif
@@ -373,7 +373,7 @@ void word_boundary()
     run_word<wchar_t>(txt_simple, none_simple, zero, word_simple, zero, zero, utf8_en_locale);
     run_word<wchar_t>(txt_all, none_all, num_all, word_all, kana_all, ideo_all, utf8_jp_locale);
 
-#ifndef BOOST_LOCALE_NO_CXX20_STRING8
+#ifdef __cpp_lib_char8_t
     std::cout << " char8_t" << std::endl;
     run_word<char8_t>(txt_empty, zero, zero, zero, zero, zero, g("ja_JP.UTF-8"));
     run_word<char8_t>(txt_simple, none_simple, zero, word_simple, zero, zero, utf8_en_locale);
diff --git a/test/test_convert.cpp b/test/test_convert.cpp
index 8752d74..d00568f 100644
--- a/test/test_convert.cpp
+++ b/test/test_convert.cpp
@@ -25,7 +25,7 @@ void test_norm(std::string orig, std::string normal, boost::locale::norm_type ty
 {
     test_normc<char>(orig, normal, type);
     test_normc<wchar_t>(to<wchar_t>(orig), to<wchar_t>(normal), type);
-#ifndef BOOST_LOCALE_NO_CXX20_STRING8
+#ifdef __cpp_lib_char8_t
     test_normc<char8_t>(to<char8_t>(orig), to<char8_t>(normal), type);
 #endif
 #ifdef BOOST_LOCALE_ENABLE_CHAR16_T
@@ -105,7 +105,7 @@ void test_main(int /*argc*/, char** /*argv*/)
     TEST_ALL_CASES;
 #undef TEST_V
 
-#ifndef BOOST_LOCALE_NO_CXX20_STRING8
+#ifdef __cpp_lib_char8_t
 #    define TEST_V(how, source_s, dest_s) TEST_A(char8_t, how, to<char8_t>(source_s), to<char8_t>(dest_s))
     TEST_ALL_CASES;
 #    undef TEST_V
diff --git a/test/test_encoding.cpp b/test/test_encoding.cpp
index 0a01d43..6f1dcc6 100644
--- a/test/test_encoding.cpp
+++ b/test/test_encoding.cpp
@@ -425,7 +425,7 @@ void test_utf_to_utf_for()
     test_from_utf_for_impls(utf<Char>(utf8_string), utf8_string, "UTF-8");
     std::cout << "---- wchar_t\n";
     test_utf_to_utf_for<Char, wchar_t>(utf8_string);
-#ifndef BOOST_LOCALE_NO_CXX20_STRING8
+#ifdef __cpp_lib_char8_t
     std::cout << "---- char8_t\n";
     test_utf_to_utf_for<Char, char8_t>(utf8_string);
 #endif
@@ -446,7 +446,7 @@ void test_utf_to_utf()
     test_utf_to_utf_for<char>();
     std::cout << "-- wchar_t\n";
     test_utf_to_utf_for<wchar_t>();
-#ifndef BOOST_LOCALE_NO_CXX20_STRING8
+#ifdef __cpp_lib_char8_t
     std::cout << "-- char8_t\n";
     test_utf_to_utf_for<char8_t>();
 #endif
@@ -643,7 +643,7 @@ void test_latin1_conversions()
     test_latin1_conversions_for<char>();
     std::cout << "-- wchar_t\n";
     test_latin1_conversions_for<wchar_t>();
-#ifndef BOOST_LOCALE_NO_CXX20_STRING8
+#ifdef __cpp_lib_char8_t
     std::cout << "-- char8_t\n";
     test_latin1_conversions_for<char8_t>();
 #endif
@@ -781,7 +781,7 @@ void test_main(int /*argc*/, char** /*argv*/)
     test_utf_for<char>();
     std::cout << "  wchar_t" << std::endl;
     test_utf_for<wchar_t>();
-#ifndef BOOST_LOCALE_NO_CXX20_STRING8
+#ifdef __cpp_lib_char8_t
     std::cout << "  char8_t" << std::endl;
     test_utf_for<char8_t>();
 #endif
diff --git a/test/test_generator.cpp b/test/test_generator.cpp
index ed3ac3c..88bfb87 100644
--- a/test/test_generator.cpp
+++ b/test/test_generator.cpp
@@ -329,7 +329,7 @@ void test_main(int /*argc*/, char** /*argv*/)
 #else
 #    define TEST_FOR_CHAR8(check) (void)0
 #endif
-#ifndef BOOST_LOCALE_NO_CXX20_STRING8
+#ifdef __cpp_lib_char8_t
 #    define TEST_FOR_STRING8(check) TEST(check)
 #else
 #    define TEST_FOR_STRING8(check) (void)0
diff --git a/test/test_ios_info.cpp b/test/test_ios_info.cpp
index 79179a8..bcffe3d 100644
--- a/test/test_ios_info.cpp
+++ b/test/test_ios_info.cpp
@@ -222,7 +222,7 @@ void test_any_string()
     TEST_EQ(s.get<char32_t>(), ascii_to<char32_t>("Char32 Pattern"));
     TEST_THROWS(s.get<char16_t>(), std::bad_cast);
 
-#ifndef BOOST_LOCALE_NO_CXX20_STRING8
+#ifdef __cpp_lib_char8_t
     s.set<char8_t>(ascii_to<char8_t>("Char8 Pattern"));
     TEST_EQ(s.get<char8_t>(), ascii_to<char8_t>("Char8 Pattern"));
     TEST_THROWS(s.get<char32_t>(), std::bad_cast);
diff --git a/test/test_message.cpp b/test/test_message.cpp
index 304d66c..80ea7d7 100644
--- a/test/test_message.cpp
+++ b/test/test_message.cpp
@@ -84,7 +84,7 @@ std::wstring same_w(std::wstring s)
     return s;
 }
 
-#ifndef BOOST_LOCALE_NO_CXX20_STRING8
+#ifdef __cpp_lib_char8_t
 std::basic_string<char8_t> same_u8(std::basic_string<char8_t> s)
 {
     return s;
@@ -376,7 +376,7 @@ void test_cntranslate(const std::string& c,
     impl::test_cntranslate<char>(c, s, p, n, expected, l, domain);
     std::cout << "  wchar_t" << std::endl;
     impl::test_cntranslate<wchar_t>(c, s, p, n, expected, l, domain);
-#ifndef BOOST_LOCALE_NO_CXX20_STRING8
+#ifdef __cpp_lib_char8_t
     std::cout << "  char8_t" << std::endl;
     impl::test_cntranslate<char8_t>(c, s, p, n, expected, l, domain);
 #endif
@@ -401,7 +401,7 @@ void test_ntranslate(const std::string& s,
     impl::test_ntranslate<char>(s, p, n, expected, l, domain);
     std::cout << "  wchar_t" << std::endl;
     impl::test_ntranslate<wchar_t>(s, p, n, expected, l, domain);
-#ifndef BOOST_LOCALE_NO_CXX20_STRING8
+#ifdef __cpp_lib_char8_t
     std::cout << "  char8_t" << std::endl;
     impl::test_ntranslate<char8_t>(s, p, n, expected, l, domain);
 #endif
@@ -425,7 +425,7 @@ void test_ctranslate(const std::string& c,
     impl::test_ctranslate<char>(c, original, expected, l, domain);
     std::cout << "  wchar_t" << std::endl;
     impl::test_ctranslate<wchar_t>(c, original, expected, l, domain);
-#ifndef BOOST_LOCALE_NO_CXX20_STRING8
+#ifdef __cpp_lib_char8_t
     std::cout << "  char8_t" << std::endl;
     impl::test_ctranslate<char8_t>(c, original, expected, l, domain);
 #endif
@@ -448,7 +448,7 @@ void test_translate(const std::string& original,
     impl::test_translate<char>(original, expected, l, domain);
     std::cout << "  wchar_t" << std::endl;
     impl::test_translate<wchar_t>(original, expected, l, domain);
-#ifndef BOOST_LOCALE_NO_CXX20_STRING8
+#ifdef __cpp_lib_char8_t
     std::cout << "  char8_t" << std::endl;
     impl::test_translate<char8_t>(original, expected, l, domain);
 #endif
@@ -570,7 +570,7 @@ void test_main(int argc, char** argv)
         TEST_EQ(same_s(bl::translate("hello")), "שלום");
         TEST_EQ(same_w(bl::translate(to<wchar_t>("hello"))), to<wchar_t>("שלום"));
 
-#ifndef BOOST_LOCALE_NO_CXX20_STRING8
+#ifdef __cpp_lib_char8_t
         TEST_EQ(same_u8(bl::translate(to<char8_t>("hello"))), to<char8_t>("שלום"));
 #endif
 #ifdef BOOST_LOCALE_ENABLE_CHAR16_T
diff --git a/test/test_std_convert.cpp b/test/test_std_convert.cpp
index bc8126e..1b8537a 100644
--- a/test/test_std_convert.cpp
+++ b/test/test_std_convert.cpp
@@ -84,7 +84,7 @@ void test_main(int /*argc*/, char** /*argv*/)
     test_char<char>();
     std::cout << "Testing wchar_t" << std::endl;
     test_char<wchar_t>();
-#ifndef BOOST_LOCALE_NO_CXX20_STRING8
+#ifdef __cpp_lib_char8_t
     std::cout << "Testing char8_t" << std::endl;
     test_char<char8_t>();
 #endif