<table border="1" cellspacing="0" cellpadding="8">
    <tr>
        <th>Issue</th>
        <td>
            <a href=https://github.com/llvm/llvm-project/issues/125955>125955</a>
        </td>
    </tr>

    <tr>
        <th>Summary</th>
        <td>
            tautological warnings for is_constant_evaluated not emitted in c++23/26 modes
        </td>
    </tr>

    <tr>
      <th>Labels</th>
      <td>
            clang:frontend,
            constexpr
      </td>
    </tr>

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

    <tr>
      <th>Reporter</th>
      <td>
          cor3ntin
      </td>
    </tr>
</table>

<pre>
    for

```cpp

int main() {
   if constexpr(std::is_constant_evaluated()) { }
}
```
We usually warn 
> 'std::is_constant_evaluated' will always evaluate to 'true' in a manifestly constant-evaluated expression [-Wconstant-evaluated]

However this warning is gone in c++23 mode

https://godbolt.org/z/KKPKvveGM
</pre>
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