<table border="1" cellspacing="0" cellpadding="8">
    <tr>
        <th>Issue</th>
        <td>
            <a href=https://github.com/llvm/llvm-project/issues/60999>60999</a>
        </td>
    </tr>

    <tr>
        <th>Summary</th>
        <td>
            allocator_traits<Alloc>::select_on_container_copy_construction rejected when used with a parameter pack
        </td>
    </tr>

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

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

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

<pre>
    ```
struct S
{
    template<class... Allocator>
    S(const Allocator&...) {}
};

template<class... Allocators>
void foo(const Allocators&... as)
{
     S s(std::allocator_traits<Allocators>::select_on_container_copy_construction(as)...); // rejected

     // OK:
     //S s({std::allocator_traits<Allocators>::select_on_container_copy_construction(as)...});
}
```

Here's the godbolt link: https://godbolt.org/z/Pear79vvr

I did try to create an example without using allocator_traits but couldn't get it to fail.

Note that there doesn't seem to be a problem in the non-variadic case
</pre>
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