<table border="1" cellspacing="0" cellpadding="8">
    <tr>
        <th>Issue</th>
        <td>
            <a href=https://github.com/llvm/llvm-project/issues/129631>129631</a>
        </td>
    </tr>

    <tr>
        <th>Summary</th>
        <td>
            [clang] the "cleanup" attribute prevents type deduction
        </td>
    </tr>

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

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

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

<pre>
    ```cpp
/* a.cpp */
int open() { return 0; }
void close(decltype(open()) *) {}
int main() {
  auto fd [[gnu::cleanup(close)]] = open();
}
```

```bash
$ clang-21 a.cpp
a.cpp:4:26: error: 'cleanup' function 'close' parameter has type 'decltype(open()) *' (aka 'int *') which is incompatible with type 'auto *'
    4 |   auto fd [[gnu::cleanup(close)]] = open();
      | ^
1 error generated.
```
</pre>
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