<table border="1" cellspacing="0" cellpadding="8">
    <tr>
        <th>Issue</th>
        <td>
            <a href=https://github.com/llvm/llvm-project/issues/123369>123369</a>
        </td>
    </tr>

    <tr>
        <th>Summary</th>
        <td>
            Offset of captures-by-copy is not observable
        </td>
    </tr>

    <tr>
      <th>Labels</th>
      <td>
            c++,
            clang:frontend,
            rejects-valid,
            lambda
      </td>
    </tr>

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

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

<pre>
    Consider the following example, courtesy of @erichkeane (https://godbolt.org/z/Tz7arYjvn):
```cpp
int x;
auto lam = [x](auto lam2){ return offsetof(decltype(lam2), x); };
return lam(lam);
```
This is arguably well-formed, because `x` refers to unnamed non-static data member of the lambda per https://eel.is/c++draft/expr.prim.lambda#capture-6.1.
</pre>
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