<table border="1" cellspacing="0" cellpadding="8">
    <tr>
        <th>Issue</th>
        <td>
            <a href=https://github.com/llvm/llvm-project/issues/63627>63627</a>
        </td>
    </tr>

    <tr>
        <th>Summary</th>
        <td>
            The alias-declaration of decltype lambda is broken in the for loop
        </td>
    </tr>

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

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

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

<pre>
    Clang accepts the following invalid code.

```cpp
template<class T>
void f() {
  for (using U = decltype([]{}.operator----); 
 auto x : "abc") { }
};

int main() {
 f<int>();
}
```
https://godbolt.org/z/dTKbnv3nE
</pre>
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