<table border="1" cellspacing="0" cellpadding="8">
    <tr>
        <th>Issue</th>
        <td>
            <a href=https://github.com/llvm/llvm-project/issues/133314>133314</a>
        </td>
    </tr>

    <tr>
        <th>Summary</th>
        <td>
            [libc++] `<regex>`: Optional empty repetitions should not match
        </td>
    </tr>

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

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

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

<pre>
    ```
> "aaa".match(/(a?)+/)
Array [ "aaa", "a" ]
> "bbebbee".match(/((b)?(be)?)+bbee/)
Array(4) [ "bbebbee", "bbe", "b", "be" ]
```
~Firefox

But in libc++, the equivalent operations return `[ "aaa", "" ]` and `[ "bbebbee", "", undefined, undefined ]`.

Full example: https://godbolt.org/z/zYYenvEdb (blatantly modified from https://github.com/microsoft/STL/issues/5365)
</pre>
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