diff --git a/include/asio/detail/config.hpp b/include/asio/detail/config.hpp
index 3c4c8e46c9..e50157c0c8 100644
--- a/include/asio/detail/config.hpp
+++ b/include/asio/detail/config.hpp
@@ -398,7 +398,7 @@
 #  if (__cplusplus >= 201703)
 #   if defined(__clang__)
 #    if defined(ASIO_HAS_CLANG_LIBCXX)
-#     if (_LIBCPP_STD_VER > 14) && defined(_LIBCPP_HAS_ALIGNED_ALLOC) \
+#     if (_LIBCPP_STD_VER > 14) && !defined(_LIBCPP_HAS_NO_ALIGNED_ALLOCATION) \
         && !defined(_LIBCPP_MSVCRT) && !defined(__MINGW32__)
 #      if defined(__ANDROID__) && (__ANDROID_API__ >= 28)
 #        define ASIO_HAS_STD_ALIGNED_ALLOC 1
@@ -423,7 +423,7 @@
 #      else // defined(__APPLE__)
 #       define ASIO_HAS_STD_ALIGNED_ALLOC 1
 #      endif // defined(__APPLE__)
-#     endif // (_LIBCPP_STD_VER > 14) && defined(_LIBCPP_HAS_ALIGNED_ALLOC)
+#     endif // (_LIBCPP_STD_VER > 14) && !defined(_LIBCPP_HAS_NO_ALIGNED_ALLOCATION)
             //   && !defined(_LIBCPP_MSVCRT) && !defined(__MINGW32__)
 #    elif defined(_GLIBCXX_HAVE_ALIGNED_ALLOC)
 #     define ASIO_HAS_STD_ALIGNED_ALLOC 1