<table border="1" cellspacing="0" cellpadding="8">
    <tr>
        <th>Issue</th>
        <td>
            <a href=https://github.com/llvm/llvm-project/issues/151826>151826</a>
        </td>
    </tr>

    <tr>
        <th>Summary</th>
        <td>
            libc++ fails to compile valid c++20 use of uses_allocator_construction_args
        </td>
    </tr>

    <tr>
      <th>Labels</th>
      <td>
            libc++
      </td>
    </tr>

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

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

<pre>
    The following C++20 program will not compile if I use -stdlib=libc++

#include <memory>
using P00 = std::pair<int, char>;
using A00 = std::allocator<P00>;
const P00 p00(1, 'a');
A00 a00;
auto r00
 = std::uses_allocator_construction_args<P00, A00, int, char>(a00, p00);

I do note there are other bugs posted against uses_allocator_construction_args, but they are marked c++23,  I believe this should be accepted in C++20 mode.

Not in important issue...I  just wanted to report it.

Thank you,

Ed Vogel
</pre>
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