[clang] [clang] Add __nullptr as a keyword to C (PR #123119)

[Erich Keane via cfe-commits]

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@@ -325,6 +325,7 @@ C Language Changes
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 - Extend clang's ``<limits.h>`` to define ``LONG_LONG_*`` macros for Android's bionic.
+- Added support for the ``__nullptr`` keyword. 
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erichkeane wrote:

```suggestion
- Exposed the the ``__nullptr`` keyword as an alias for ``nullptr`` in all C language modes.
```

Perhaps??

https://github.com/llvm/llvm-project/pull/123119