[clang] Warning for incorrect useof 'pure' attribute (PR #78200)

[Aaron Ballman via cfe-commits]

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@@ -560,7 +560,8 @@ Improvements to Clang's diagnostics
 - Clang now diagnoses unexpanded packs within the template argument lists of function template specializations.
 - Clang now diagnoses attempts to bind a bitfield to an NTTP of a reference type as erroneous
   converted constant expression and not as a reference to subobject.
-
+- Clang now diagnoses incorrect usage of 'const' and 'pure' attributes (``-Wincorrect-pure-usage``),
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AaronBallman wrote:

```suggestion
- Clang now diagnoses incorrect usage of ``const`` and ``pure`` attributes (``-Wincorrect-pure-usage``),
```

https://github.com/llvm/llvm-project/pull/78200