<table border="1" cellspacing="0" cellpadding="8">
    <tr>
        <th>Issue</th>
        <td>
            <a href=https://github.com/llvm/llvm-project/issues/76375>76375</a>
        </td>
    </tr>

    <tr>
        <th>Summary</th>
        <td>
            Clang wrongly warns about empty variadic argument lists for macros
        </td>
    </tr>

    <tr>
      <th>Labels</th>
      <td>
            clang
      </td>
    </tr>

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

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

<pre>
    Clang warns about empty variadic argument lists for macros if [-Wgnu-zero-variadic-macro-arguments](https://releases.llvm.org/17.0.1/tools/clang/docs/DiagnosticsReference.html#id380) is activated. This warning is wrong when compiling for C++ 20 or later mode. C++ 20 and later explicitly allow empty variadic argument lists for macros: https://eel.is/c++draft/cpp.replace.general#5

> If the [identifier-list](https://eel.is/c++draft/cpp.pre#nt:identifier-list) in the macro definition does not end with an ellipsis, the number of arguments (including those arguments consisting of no preprocessing tokens) in an invocation of a function-like macro shall equal the number of parameters in the macro definition[.](https://eel.is/c++draft/cpp.replace.general#5.sentence-1)
Otherwise, there shall be **at least as many arguments in the invocation as there are parameters in the macro definition (excluding the ...)**[.](https://eel.is/c++draft/cpp.replace.general#5.sentence-2)
There shall exist a ) preprocessing token that terminates the invocation[.](https://eel.is/c++draft/cpp.replace.general#5.sentence-3)
</pre>
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