<table border="1" cellspacing="0" cellpadding="8">
    <tr>
        <th>Issue</th>
        <td>
            <a href=https://github.com/llvm/llvm-project/issues/143657>143657</a>
        </td>
    </tr>

    <tr>
        <th>Summary</th>
        <td>
            [clang-format] Apply different ColumnLimit for comments
        </td>
    </tr>

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

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

    <tr>
      <th>Reporter</th>
      <td>
          M-Fabian
      </td>
    </tr>
</table>

<pre>
    We are using clang-format for some time now and enjoy the auto-formatting for the most part.

One issue we have is with commented out code. If a line is slightly shorter than the column limit, then by commenting it out, it becomes 3 characters longer due to "// ", thus exceeding the column limit. clang-format then reformats the comment, thereby breaking the code snippet. Commenting it back in results in a syntax error.

The solution seems to be straightforward: Allow comment lines to have a ColumnLimit + 3 before adding a line break.

Consider the following example for illustration:

    // original code with a 80 character line
    void f()
    {
      cout << "This is a looooooooooooooooong line which I need to comment out.\n";
 int k = 5;
    }
    
    // comment code out, line becomes 83 characters wide and is adjusted.
    void f()
    {
      //   cout << "This is a looooooooooooooooong line which I need to comment
      // out.\n"; int k = 5;
    }
    
    // comment code back in, resulting in syntax errors
    void f()
    {
      cout << "This is a looooooooooooooooong line which I need to comment
              out.\n "; int k = 5;
    }

</pre>
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