[clang] [clang][ExprConst] allow single element access of vector object to be constant expression (PR #72607)

[Yuanfang Chen via cfe-commits]

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@@ -144,6 +144,9 @@ sections with improvements to Clang's support for those languages.
 
 C++ Language Changes
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+- Allow single element access of vector object to be constant expression.
+  Supports the `V.xyzw` syntax and other tidbits as seen in OpenCL.
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yuanfang-chen wrote:

done

https://github.com/llvm/llvm-project/pull/72607