<table border="1" cellspacing="0" cellpadding="8">
    <tr>
        <th>Issue</th>
        <td>
            <a href=https://github.com/llvm/llvm-project/issues/125188>125188</a>
        </td>
    </tr>

    <tr>
        <th>Summary</th>
        <td>
            [libc++] basic_string::max_size() is broken for small sizes
        </td>
    </tr>

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

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

    <tr>
      <th>Reporter</th>
      <td>
          philnik777
      </td>
    </tr>
</table>

<pre>
    `max_size()` currently checks if the allocator's `max_size() <= numeric_limits<size_type>::max() / 2`, but then subtracts an alignment, causing an overflow for values less than the alignment. We should probably just diagnose when the `max_size()` of the allocator is so small that our string implementation is just broken (e.g. `max_size() < SSO size`).
</pre>
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