<table border="1" cellspacing="0" cellpadding="8">
    <tr>
        <th>Issue</th>
        <td>
            <a href=https://github.com/llvm/llvm-project/issues/63181>63181</a>
        </td>
    </tr>

    <tr>
        <th>Summary</th>
        <td>
            Requires-expressions don't seem to evaluate pack expansions
        </td>
    </tr>

    <tr>
      <th>Labels</th>
      <td>
            clang:frontend,
            accepts-invalid,
            concepts
      </td>
    </tr>

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

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

<pre>
    [GCC test `concepts-lambda19` compiles when it shouldn't](https://godbolt.org/z/cjaKdKTcY).
```cpp
// PR c++/103706
// RUN: %clang_cc1 -std=c++20 -fsyntax-only -verify %s

template<class T> concept C = __is_same(T, int);

template<class... Ts> void f() {
  ([]() requires C<Ts> { return Ts(); }(), ...); // this expands to C<char> for the second one, which is false
}

template void f<int, int, int>();
template void f<int, int, char>();
```

Note that this also happens with
```cpp
int main()
{
  f<int, int, char>();
}
```
</pre>
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