[clang] [clang-tools-extra] [llvm] [clang] Add test for CWG472 (PR #67948)

[Aaron Ballman via cfe-commits]

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@@ -2871,7 +2871,7 @@ <h2 id="cxxdr">C++ defect report implementation status</h2>
     <td><a href="https://cplusplus.github.io/CWG/issues/472.html">472</a></td>
     <td>drafting</td>
     <td>Casting across protected inheritance</td>
-    <td align="center">Not resolved</td>
+    <td class="none" align="center">No</td>
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AaronBallman wrote:

I don't think we should read tea leaves on unresolved issues; WG21 and WG14 will change direction on unresolved issues sometimes and so documenting anything about how we compare to the proposed resolution runs a reasonably high risk of getting stale. I think it's fine to have tests to document how we currently behave (and then if the test breaks, it's a reminder to whoever made the change to go look at the current status of the issue). But maybe we should just leave these as `Not Resolved` and make no other claims?

Otherwise, the information I think that's most accurate is whether Clang does or does not exhibit the issue that was reported (when possible). At least that tells the user "if you think this is an issue, Clang has that behavior."

https://github.com/llvm/llvm-project/pull/67948