<table border="1" cellspacing="0" cellpadding="8">
    <tr>
        <th>Issue</th>
        <td>
            <a href=https://github.com/llvm/llvm-project/issues/79010>79010</a>
        </td>
    </tr>

    <tr>
        <th>Summary</th>
        <td>
            [libc++][modules] Guard #error against MSVC headers on Windows
        </td>
    </tr>

    <tr>
      <th>Labels</th>
      <td>
            libc++
      </td>
    </tr>

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

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

<pre>
    The libc++ test suite sees the MSVC STL headers and may conclude these are libc++ headers when inspecting the name. Modules guard against forgetting to export new headers, and this gets false positives if it finds MSVC STL headers.
</pre>
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