<table border="1" cellspacing="0" cellpadding="8">
    <tr>
        <th>Issue</th>
        <td>
            <a href=https://github.com/llvm/llvm-project/issues/112931>112931</a>
        </td>
    </tr>

    <tr>
        <th>Summary</th>
        <td>
            Unexpected warning for pack indexing
        </td>
    </tr>

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

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

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

<pre>
    Suppose we use the feature test macro to only use pack indexing when available
```
template <std::size_t N, typename... Args>
constexpr auto my_element(Args... args) {
#if __cpp_pack_indexing >=  202311L
  return args...[N];
#else
  // Do something else
#endif
}
```
A compiler warning is emitted when compiling for C++23 or earlier
```
<source>:13:16: warning: pack indexing is a C++2c extension [-Wc++26-extensions]
   13 |         return args...[N];
      |                ^
1 warning generated.
```
</pre>
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