<table border="1" cellspacing="0" cellpadding="8">
    <tr>
        <th>Issue</th>
        <td>
            <a href=https://github.com/llvm/llvm-project/issues/82107>82107</a>
        </td>
    </tr>

    <tr>
        <th>Summary</th>
        <td>
            Investigate backdeployment tests.
        </td>
    </tr>

    <tr>
      <th>Labels</th>
      <td>
            new issue
      </td>
    </tr>

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

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

<pre>
    ```suggestion
// XFAIL: using-built-library-before-llvm-19
```

_Originally posted by @ldionne in https://github.com/llvm/llvm-project/pull/76467#discussion_r1488334399_

Applying this suggestion failed for the "Apple system" [CI](https://buildkite.com/llvm-project/libcxx-ci/builds/33635#018da3e0-d01f-4ba4-a04f-60bb5daa4679). Based on the CI configuration this does not seem like a back-deployment target. Maybe there is something off in the backdeployment detection. 
</pre>
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