2007-08-16 06:17:17

by Eugene Teo

Subject: [PATCH] Make checkpatch rant about trailing ; at the end of "if" expr

Make checkpatch rant about trailing ; at the end of "if" expression.

Thanks to Auke for the regexp.

Signed-off by: Eugene Teo <[email protected]>

--- checkpatch.pl-0.09.default 2007-08-03 23:31:40.000000000 +0800
+++ checkpatch.pl-0.09 2007-08-16 13:18:40.000000000 +0800
@@ -1091,6 +1091,12 @@ sub process {
CHK("__setup appears un-documented -- check Documentation/kernel-parameters.txt\n" . $herecurr);
}
}
+
+# checks for trailing ; at the end of "if" expression
+ if ($line =~ /\bif\s*\([^\)]*\)\s*\;/) {
+ my $herevet = "$here\n" . cat_vet($line) . "\n";
+ ERROR("trailing ;\n" . $herevet);
+ }
}

if ($chk_patch && !$is_patch) {

2007-08-16 09:22:35

by Andy Whitcroft

Subject: Re: [PATCH] Make checkpatch rant about trailing ; at the end of "if" expr

Eugene Teo wrote:
> Make checkpatch rant about trailing ; at the end of "if" expression.
>
> Thanks to Auke for the regexp.
>
> Signed-off by: Eugene Teo <[email protected]>
>
> --- checkpatch.pl-0.09.default 2007-08-03 23:31:40.000000000 +0800
> +++ checkpatch.pl-0.09 2007-08-16 13:18:40.000000000 +0800
> @@ -1091,6 +1091,12 @@ sub process {
> CHK("__setup appears un-documented -- check Documentation/kernel-parameters.txt\n" . $herecurr);
> }
> }
> +
> +# checks for trailing ; at the end of "if" expression
> + if ($line =~ /\bif\s*\([^\)]*\)\s*\;/) {
> + my $herevet = "$here\n" . cat_vet($line) . "\n";
> + ERROR("trailing ;\n" . $herevet);
> + }
> }
>
> if ($chk_patch && !$is_patch) {

Heh, you are the second person to suggest this check today, do I detect
some ripped out hair due to one of these!

I've taken this idea and expanded it to cover if, for and while which
can all suffer from this. Using the relative indent to work out which
are valid combinations:

WARNING: Trailing semicolon indicates no statements, indent implies
otherwise
#28: FILE: Z17.c:25:
+ if (foo);
+ return 10;
WARNING: Trailing semicolon indicates no statements, indent implies
otherwise
#31: FILE: Z17.c:28:
+ for (a; b; c);
+ a += *b;

Thanks for the patch.

-apw

2007-08-17 12:04:12

by Jan Engelhardt

Subject: Re: [PATCH] Make checkpatch rant about trailing ; at the end of "if" expr

On Aug 16 2007 10:21, Andy Whitcroft wrote:
>> + if ($line =~ /\bif\s*\([^\)]*\)\s*\;/) {
>
>Heh, you are the second person to suggest this check today, do I detect
>some ripped out hair due to one of these!
>
>I've taken this idea and expanded it to cover if, for and while which
>can all suffer from this. Using the relative indent to work out which
>are valid combinations:

But. The above regex does not seem to handle

if ((a = b));
oops;

I have tried to come up with a superduper regex that handles multiple
(), but my regex fu seems to stop above two pairs of ().

#!/usr/bin/perl

@check = (
q"if ((ptr = malloc(bong, GFP)) == NULL) ; (oopsie) ;",
q"if ((ptr = malloc(bong, GFP)) == NULL) (alright);",
q"if ( ({ bool evil = (true); evil; }) ) ; (oopsie) ;",
q"if ( ({ bool evil = (true); evil; }) ) (alright);",
q"if((()));",
);

my $r = qr/\s*\(\s*(??{$r})?\s*\)\s*|\s*\(\s*[^()]+\s*\)\s*/;

foreach (@check) {
if ($_ =~ /(if|for|while)$r;/) {
print "ok $_\n";
}
}


Jan
--