<table border="1" cellspacing="0" cellpadding="8">
    <tr>
        <th>Issue</th>
        <td>
            <a href=https://github.com/llvm/llvm-project/issues/125810>125810</a>
        </td>
    </tr>

    <tr>
        <th>Summary</th>
        <td>
            [Clang] `-Wunused-variable` false negative when not all structured bindings are marked `maybe_unused`
        </td>
    </tr>

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

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

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

<pre>
    Clang doesn't emit warning when all structured bindings are unused but not all structured bindings are marked `maybe_unused`.

```cpp
struct S {
  int a, b;
};

void test(S s) {
  auto &[a1, _] = s; // "unused variable" warning emitted expectedly
  auto &[a2, b2 [[maybe_unused]]] = s; // no warning emitted unexpectedly
  auto &[_, b3 [[maybe_unused]]] = s; // no warning emitted expectedly
}
```

Compiler Explorer: <https://godbolt.org/z/vnf9Ma3nb>
</pre>
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