<table border="1" cellspacing="0" cellpadding="8">
    <tr>
        <th>Issue</th>
        <td>
            <a href=https://github.com/llvm/llvm-project/issues/86686>86686</a>
        </td>
    </tr>

    <tr>
        <th>Summary</th>
        <td>
            `std::variant<std::string>{}.index()` is not an integral constant expression
        </td>
    </tr>

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

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

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

<pre>
    Clang rejects the following. 
Not sure if it's just because a certain language feature isn't implemented yet, correct me if I'm missing something.

```cpp
#include <variant>
#include <string>

static_assert(std::variant<std::string>{}.index() == 0);
```
https://godbolt.org/z/8cTnafsMd
</pre>
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