<table border="1" cellspacing="0" cellpadding="8">
    <tr>
        <th>Issue</th>
        <td>
            <a href=https://github.com/llvm/llvm-project/issues/84859>84859</a>
        </td>
    </tr>

    <tr>
        <th>Summary</th>
        <td>
            Parameter pack incorrectly accepted not at the end of template parameter list
        </td>
    </tr>

    <tr>
      <th>Labels</th>
      <td>
            new issue
      </td>
    </tr>

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

    <tr>
      <th>Reporter</th>
      <td>
          Boris-Rasin
      </td>
    </tr>
</table>

<pre>
    clang 18.1.0

This correctly fails to compile:
"error: template parameter pack must be the last template parameter"

```c++
template<typename..., typename...>
class C;
```

This is incorrectly accepted:

```c++
template <template<typename..., typename...> class C>
struct test;
```

Related: https://github.com/llvm/llvm-project/issues/84857
</pre>
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