-#if (defined(__APPLE__) && defined(_LIBCPP_HAS_C11_FEATURES)) || defined(__ANDROID__) || defined(__OpenBSD__) || (defined(__GLIBCXX__) && !defined(_GLIBCXX_HAVE_ALIGNED_ALLOC) && !defined(_WIN32))
- return aligned_alloc(alignment, size);
-#elif (defined(_WIN32) || (defined(__APPLE__) && !defined(_LIBCPP_HAS_C11_FEATURES)))
+
+#if defined(POSIXALIGNEDALLOC)
+ void *mem;
+ return posix_memalign(&mem, alignment, size) ? nullptr : mem;
+#elif defined(_WIN32)