Re: Please fix or revert: [PATCH] checkpatch: add --strict tests for braces, comments and casts

[Randy Dunlap <rdunlap@xenotime.net>]

On 04/16/2012 02:17 AM, Ingo Molnar wrote:

> 
> This recent checkpatch commit, added in v3.4-rc1:
> 
>   aad4f6149831 checkpatch: add --strict tests for braces, comments and casts
> 
> made the default checkpatch run complain about the following 
> perfectly fine multi-line comment block:
> 
> +               rdp->qlen_lazy = 0;
> +               rdp->qlen = 0;
> +
> +               /*
> +                * Adopt all callbacks.  The outgoing CPU was in no shape
> +                * to advance them, so make them all go through a full
> +                * grace period.
> +                */
> +               *receive_rdp->nxttail[RCU_NEXT_TAIL] = rdp->nxtlist;
> 
> With:
> 
>  CHECK: Don't begin block comments with only a /* line, use /* comment...
> 
> #80: FILE: kernel/rcutree.c:1428:
> +
> +		/*
> 
> Which is an obviously bogus warning: the comment is perfectly 
> fine and it has the form that Documentation/CodingStyle 
> specifically recommends:
> 
> |                 Chapter 8: Commenting
> |
> | [...]
> |
> | The preferred style for long (multi-line) comments is:
> |
> |        /*
> |         * This is the preferred style for multi-line
> |         * comments in the Linux kernel source code.
> |         * Please use it consistently.
> |         *
> |         * Description:  A column of asterisks on the left side,
> |         * with beginning and ending almost-blank lines.
> |         */
> |
> 
> Please turn this new warning off by default, or fix the check, 
> or revert it. (The revert below applies cleanly on top of latest 
> -git and solves the warning for me.)
> 
> Thanks,
> 
> 	Ingo
> 
> This reverts commit aad4f61498314d41d047ea2161b7bd7237b72d33.
> 
> Signed-off-by: Ingo Molnar <mingo@kernel.org>


Acked-by: Randy Dunlap <rdunlap@xenotime.net>

Thanks.

> ---
>  scripts/checkpatch.pl |   40 ++++++++--------------------------------
>  1 files changed, 8 insertions(+), 32 deletions(-)
> 
> diff --git a/scripts/checkpatch.pl b/scripts/checkpatch.pl
> index de639ee..6217093 100755
> --- a/scripts/checkpatch.pl
> +++ b/scripts/checkpatch.pl
> @@ -1864,17 +1864,6 @@ sub process {
>  			}
>  		}
>  
> -		if ($line =~ /^\+.*\*[ \t]*\)[ \t]+/) {
> -			CHK("SPACING",
> -			    "No space is necessary after a cast\n" . $hereprev);
> -		}
> -
> -		if ($rawline =~ /^\+[ \t]*\/\*[ \t]*$/ &&
> -		    $prevrawline =~ /^\+[ \t]*$/) {
> -			CHK("BLOCK_COMMENT_STYLE",
> -			    "Don't begin block comments with only a /* line, use /* comment...\n" . $hereprev);
> -		}
> -
>  # check for spaces at the beginning of a line.
>  # Exceptions:
>  #  1) within comments
> @@ -2987,8 +2976,7 @@ sub process {
>  			#print "chunks<$#chunks> linenr<$linenr> endln<$endln> level<$level>\n";
>  			#print "APW: <<$chunks[1][0]>><<$chunks[1][1]>>\n";
>  			if ($#chunks > 0 && $level == 0) {
> -				my @allowed = ();
> -				my $allow = 0;
> +				my $allowed = 0;
>  				my $seen = 0;
>  				my $herectx = $here . "\n";
>  				my $ln = $linenr - 1;
> @@ -2999,7 +2987,6 @@ sub process {
>  					my ($whitespace) = ($cond =~ /^((?:\s*\n[+-])*\s*)/s);
>  					my $offset = statement_rawlines($whitespace) - 1;
>  
> -					$allowed[$allow] = 0;
>  					#print "COND<$cond> whitespace<$whitespace> offset<$offset>\n";
>  
>  					# We have looked at and allowed this specific line.
> @@ -3012,34 +2999,23 @@ sub process {
>  
>  					$seen++ if ($block =~ /^\s*{/);
>  
> -					#print "cond<$cond> block<$block> allowed<$allowed[$allow]>\n";
> +					#print "cond<$cond> block<$block> allowed<$allowed>\n";
>  					if (statement_lines($cond) > 1) {
>  						#print "APW: ALLOWED: cond<$cond>\n";
> -						$allowed[$allow] = 1;
> +						$allowed = 1;
>  					}
>  					if ($block =~/\b(?:if|for|while)\b/) {
>  						#print "APW: ALLOWED: block<$block>\n";
> -						$allowed[$allow] = 1;
> +						$allowed = 1;
>  					}
>  					if (statement_block_size($block) > 1) {
>  						#print "APW: ALLOWED: lines block<$block>\n";
> -						$allowed[$allow] = 1;
> +						$allowed = 1;
>  					}
> -					$allow++;
>  				}
> -				if ($seen) {
> -					my $sum_allowed = 0;
> -					foreach (@allowed) {
> -						$sum_allowed += $_;
> -					}
> -					if ($sum_allowed == 0) {
> -						WARN("BRACES",
> -						     "braces {} are not necessary for any arm of this statement\n" . $herectx);
> -					} elsif ($sum_allowed != $allow &&
> -						 $seen != $allow) {
> -						CHK("BRACES",
> -						    "braces {} should be used on all arms of this statement\n" . $herectx);
> -					}
> +				if ($seen && !$allowed) {
> +					WARN("BRACES",
> +					     "braces {} are not necessary for any arm of this statement\n" . $herectx);
>  				}
>  			}
>  		}
> --


-- 
~Randy