[libcxx-commits] [libcxx] [libc++] stddef.h needs to #include_next for the new clang __need_ macros (PR #86252)

[Louis Dionne via libcxx-commits]

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@@ -7,16 +7,27 @@
 //
 //===----------------------------------------------------------------------===//
 
-#if defined(__need_ptrdiff_t) || defined(__need_size_t) || defined(__need_wchar_t) || defined(__need_NULL) ||          \
-    defined(__need_wint_t)
+#if defined(__need_ptrdiff_t) || defined(__need_size_t) || defined(__need_rsize_t) || defined(__need_wchar_t) ||       \
----------------
ldionne wrote:

Yes, my simplified version of the header does fail that test, however I think that test is misguided. Basically, I don't buy this:

> The problem is that some headers need to declare just size_t, and it's a problem if anything else gets declared. 

We would only be defining `nullptr_t` in addition to whatever gets defined in the `#include_next <stddef.h>`. However that's already the status quo and things work, so I don't think this can be a problem.

https://github.com/llvm/llvm-project/pull/86252