[clang] Add tests for CWG issues 6, 212, 232, 2823. (PR #165633)

[Vlad Serebrennikov via cfe-commits]

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@@ -230,6 +230,37 @@ namespace cwg211 { // cwg211: 2.7
   };
 } // namespace cwg211
 
+namespace cwg212 { // cwg212: yes
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Endilll wrote:

> I suppose it'd make sense to remove "yes" entirely as an option, given we're so close

I discussed that with other maintainers, and it was met with some resistance. I guess DR status page for C being filled with "yes" didn't help.

(There is a dream for C DR tests to follow the example of C++ DR tests, including the script to automatically generate the status page.)

https://github.com/llvm/llvm-project/pull/165633