<table border="1" cellspacing="0" cellpadding="8">
    <tr>
        <th>Issue</th>
        <td>
            <a href=https://github.com/llvm/llvm-project/issues/102169>102169</a>
        </td>
    </tr>

    <tr>
        <th>Summary</th>
        <td>
            Clang crashes on nested lambdas with parameter packs
        </td>
    </tr>

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

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

    <tr>
      <th>Reporter</th>
      <td>
          Taw3e8
      </td>
    </tr>
</table>

<pre>
    This code crashes: https://godbolt.org/z/zdGvoE6h4
```cpp
template <std::size_t N, std::size_t M>
concept C = requires {
 []<std::size_t... Is>(std::index_sequence<Is...>)
    requires requires {
        []<std::size_t... Js>(std::index_sequence<Js...>)
 requires requires { true; }
        {}(std::make_index_sequence<M>{});
 }
    {}(std::make_index_sequence<N>{});
};
```
But without the nested lambda it's fine: https://godbolt.org/z/P8svEfjYd

Some issues that seem related: https://github.com/llvm/llvm-project/issues/86361, https://github.com/llvm/llvm-project/issues/93256, https://github.com/llvm/llvm-project/issues/85667

</pre>
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