[clang] [C++] Expose nullptr_t from stddef.h in C++ mode (PR #154599)

[Nikolas Klauser via cfe-commits]

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@@ -16,7 +16,8 @@
 #define _NULLPTR_T
 
 #ifdef __cplusplus
-#if defined(_MSC_EXTENSIONS) && defined(_NATIVE_NULLPTR_SUPPORTED)
+#if __cplusplus >= 201103L ||                                                  \
+    (defined(_MSC_EXTENSIONS) && defined(_NATIVE_NULLPTR_SUPPORTED))
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philnik777 wrote:

Sorry, I meant libc++'s `stddef.h` with "our `stddef.h`". We currently have a wrapping header to provide `nullptr_t` correctly: https://godbolt.org/z/W41dKKbd4.

https://github.com/llvm/llvm-project/pull/154599