<table border="1" cellspacing="0" cellpadding="8">
    <tr>
        <th>Issue</th>
        <td>
            <a href=https://github.com/llvm/llvm-project/issues/96408>96408</a>
        </td>
    </tr>

    <tr>
        <th>Summary</th>
        <td>
            Cannot use lambda expression within Requires
        </td>
    </tr>

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

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

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

<pre>
    This program
```
template<typename T>
concept C = requires(T t) {
    [x=t](){ return x; }();
};

static_assert(C<int>);
```
seems valid, and it is accepted by GCC and MSVC. Unfortunately, Clang rejects it with the
```
error: constraint variable 't' cannot be used in an evaluated context
    3 |     [x=t](){ return x; }();
```
Online demo: https://gcc.godbolt.org/z/37v5bWKvv
</pre>
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