[libcxx-commits] [libcxx] [libcxxabi] [libc++][RFC] Always define internal feature test macros (PR #89178)

[Louis Dionne via libcxx-commits]

================
@@ -419,7 +418,7 @@ inline Tp const& DoNotOptimize(Tp const& value) {
 #  define TEST_HAS_NO_FILESYSTEM
 #endif
 
-#if defined(_LIBCPP_HAS_NO_C8RTOMB_MBRTOC8)
+#if defined(_LIBCPP_HAS_C8RTOMB_MBRTOC8) && !_LIBCPP_HAS_C8RTOMB_MBRTOC8
----------------
ldionne wrote:

```suggestion
#if defined(_LIBCPP_VERSION) && !_LIBCPP_HAS_C8RTOMB_MBRTOC8
```

https://github.com/llvm/llvm-project/pull/89178