<table border="1" cellspacing="0" cellpadding="8">
    <tr>
        <th>Issue</th>
        <td>
            <a href=https://github.com/llvm/llvm-project/issues/78069>78069</a>
        </td>
    </tr>

    <tr>
        <th>Summary</th>
        <td>
            CWG472 is not implemented
        </td>
    </tr>

    <tr>
      <th>Labels</th>
      <td>
            c++,
            clang:frontend
      </td>
    </tr>

    <tr>
      <th>Assignees</th>
      <td>
      </td>
    </tr>

    <tr>
      <th>Reporter</th>
      <td>
          Endilll
      </td>
    </tr>
</table>

<pre>
    Richard suggested the following approach in https://github.com/llvm/llvm-project/pull/67948#issuecomment-1890010504:
> I think a rule even more similar to [class.protected] should be implemented: if we rely on a conversion from a class N to a class B, if N is a protected base class of B (if a public member of B would be a protected member of N), then additionally require that N is either C or a class derived from C (where C is the class granting access, as in [class.protected]).
>
> I'd suggest we implement that as a warning, given that the standard is clear and other implementers accept.
</pre>
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