Re: CodingStyle vs checkpatch for block comments

[Joe Perches <joe@perches.com>]

On Tue, 2012-04-03 at 14:08 -0400, Chris Metcalf wrote:
> On 4/3/2012 1:41 PM, Joe Perches wrote:
> > On Tue, 2012-04-03 at 13:25 -0400, Chris Metcalf wrote:
> >> The relevant code in checkpatch.pl is:
> >>
> >>                 if ($rawline =~ /^\+[ \t]*\/\*[ \t]*$/ &&
> >>                     $prevrawline =~ /^\+[ \t]*$/) {
> >>                         CHK("BLOCK_COMMENT_STYLE",
> >>                             "Don't begin block comments with only a /*
> >> line, use /* comment...\n" . $hereprev);
> >>                 }
> >>
> >> So, my questions -
> >>
> >> 1. I'm not sure what the regexps are really trying to avoid.  Presumably a
> >> blank line followed by a block comment is OK?  Certainly the kernel sources
> >> are full of this construct.
> > It emits a check message on
> > <blank line>
> > 	/*
> >
> > but not
> > <blank line>
> > 	/* some actual comment
> 
> Right, I understand what the regexps do, I'm just not clear on what the
> rationale is.

Fewer vertical lines for block comments.

This block comment uses a lot of lines:

		some_code();
	}

	/*
	 * Some multiline
	 * block comment
	 */

	some_more_code();

This is 1 fewer line

		some_code();
	}

	/* Some multline
	 * block comment
	 */

	some_more_code();

>   Is it trying to ensure that multi-line block comments are
> never preceded by a blank line?

No.

> Is it trying to change the format of block
> comments such that they either are preceded by a blank line, or a
> standalone "/*", but not both?  Confusing.

It's suggesting that a multi line comment block
starting with only a /* wastes space on vertically
challenged terminals.

Some of my friends are also vertically challenged,
so I understand the desire to be efficient.

> Obviously removing it would be an easy fix. :-)  I don't know if it makes
> sense to advocate for different kernel comment styles in different subtrees.

<shrug>  I don't care much either way.

The content of the comment is more important.