<table border="1" cellspacing="0" cellpadding="8">
    <tr>
        <th>Issue</th>
        <td>
            <a href=https://github.com/llvm/llvm-project/issues/124612>124612</a>
        </td>
    </tr>

    <tr>
        <th>Summary</th>
        <td>
            C++20 coroutine with stateful allocator results in ASAN stack-use-after-scope starting with clang 19
        </td>
    </tr>

    <tr>
      <th>Labels</th>
      <td>
            clang
      </td>
    </tr>

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

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

<pre>
    When trying to upgrade to clang 19, we ran into an issue where an ASAN violation is reported in code using a stateful allocator on a promise type. I've tried to reduce the repro in https://godbolt.org/z/soPP6x9rx which shows 18 and 19 side-by-side. It looks like the `stack-use-after-scope` occurs during the construction of the coroutine frame.
</pre>
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