<table border="1" cellspacing="0" cellpadding="8">
    <tr>
        <th>Issue</th>
        <td>
            <a href=https://github.com/llvm/llvm-project/issues/75248>75248</a>
        </td>
    </tr>

    <tr>
        <th>Summary</th>
        <td>
            Error message on missing `typename` in parameter pack expansion does not note lack of `typename`
        </td>
    </tr>

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

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

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

<pre>
    In the following code:
```
template <typename... Ts> struct S;

template <typename T>
using U1 = S<T::Type>;

template <typename... Ts>
using U2 = S<Ts::Type...>;
```
Both `U1` and `U2` are missing `typename` inside the `<>`. The compiler helpfully suggests I add it for `U1`. It does not do so for `U2`. I think it should. This would have saved an hour of my time today tracking down what was wrong and how to fix it, since I'd never tried to using a member type alias inside a parameter pack expansion before.

Live example: https://godbolt.org/z/3c8aWMEnb
</pre>
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