<table border="1" cellspacing="0" cellpadding="8">
    <tr>
        <th>Issue</th>
        <td>
            <a href=https://github.com/llvm/llvm-project/issues/130753>130753</a>
        </td>
    </tr>

    <tr>
        <th>Summary</th>
        <td>
            False positive `clangd(unused-includes)` with deduced return `operator<=>`
        </td>
    </tr>

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

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

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

<pre>
    The following code raises `clang(implied_comparison_category_type_not_found)`:
```cpp
struct awoo {
 friend auto operator<=>(awoo,awoo) = default;
};
```
The following code then raises: `clangd(unused-includes)`:
```cpp
#include <compare>
struct awoo {
    friend auto operator<=>(awoo,awoo) = default;
};
```
Not sure how to reproduce on Compiler Explorer.

To fix it, one must use `std::strong_ordering` instead of `auto`.
</pre>
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