<table border="1" cellspacing="0" cellpadding="8">
    <tr>
        <th>Issue</th>
        <td>
            <a href=https://github.com/llvm/llvm-project/issues/132561>132561</a>
        </td>
    </tr>

    <tr>
        <th>Summary</th>
        <td>
            [clang-tidy] Check request: modernize-use-elifdef-and-elifndef
        </td>
    </tr>

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

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

    <tr>
      <th>Reporter</th>
      <td>
          denzor200
      </td>
    </tr>
</table>

<pre>
    
C++23 suggests us `#elifdef` and `#elifndef` as a new way to write directives in a long conditional preprocessing block.
Needs a check that will find usages of `#elif` followed by `defined identifier`(or `!defined identifier`) and will suggest to change it to `#elifdef identifier`(or `#elifndef identifier`).

BEFORE:
```
#ifdef CPU
    std::cout << "4: no1\n";
#elif defined GPU
    std::cout << "4: no2\n";
#elif !defined RAM
    std::cout << "4: yes\n";
#endif
```

AFTER:
```
#ifdef CPU
    std::cout << "4: no1\n";
#elifdef GPU
    std::cout << "4: no2\n";
#elifndef RAM
    std::cout << "4: yes\n";
#endif
```

</pre>
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