<table border="1" cellspacing="0" cellpadding="8">
    <tr>
        <th>Issue</th>
        <td>
            <a href=https://github.com/llvm/llvm-project/issues/61095>61095</a>
        </td>
    </tr>

    <tr>
        <th>Summary</th>
        <td>
            libc++ std::variant adds two words of overhead, rather than one, on Windows
        </td>
    </tr>

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

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

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

<pre>
    I don't have an easy standalone reproducer, mostly because I don't see clang-cl on godbolt or anything, but here's a static_assert in Chromium:
https://chromium-review.googlesource.com/c/chromium/src/+/4294508
https://logs.chromium.org/logs/chromium/buildbucket/cr-buildbucket/8787813272405926289/+/u/compile__with_patch_/stdout

While `absl::variant<size_t, char>` is 16 bytes as expected, `std::variant<size_t, char>`, on just Windows is 24 bytes.
</pre>
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