<table border="1" cellspacing="0" cellpadding="8">
    <tr>
        <th>Issue</th>
        <td>
            <a href=https://github.com/llvm/llvm-project/issues/78184>78184</a>
        </td>
    </tr>

    <tr>
        <th>Summary</th>
        <td>
            [libc++][format] file_clock should always use UTC as timezone
        </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>
     Actually this clock should always have UTC at timezone, this GMT is wrong too.
[[time.format]/12](http://eel.is/c++draft/time.format#12)
```
Remarks: If %Z is used, it is replaced with STATICALLY-WIDEN<charT>("UTC").
```

_Originally posted by @mordante in https://github.com/llvm/llvm-project/pull/75526#discussion_r1452581034_
 
</pre>
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