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Message-ID: <67247b2d51aa8b2da7377e400e9191733144ed0f.camel@perches.com>
Subject: Re: [PATCH v2] checkpatch: fix false positives in REPEATED_WORD
 warning
From:   Joe Perches <joe@perches.com>
To:     Aditya <yashsri421@gmail.com>
Cc:     linux-kernel@vger.kernel.org,
        linux-kernel-mentees@lists.linuxfoundation.org,
        lukas.bulwahn@gmail.com, dwaipayanray1@gmail.com
Date:   Thu, 22 Oct 2020 12:33:04 -0700
In-Reply-To: <5121bf7c-a126-6178-62ff-e54f0bb4cb6e@gmail.com>
References: <20201022145021.28211-1-yashsri421@gmail.com>
         <4cbbd8d8b6c4d686f71648af8bc970baa4b0ee9b.camel@perches.com>
         <5121bf7c-a126-6178-62ff-e54f0bb4cb6e@gmail.com>
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On Fri, 2020-10-23 at 00:44 +0530, Aditya wrote:
> On 22/10/20 9:40 pm, Joe Perches wrote:
> > On Thu, 2020-10-22 at 20:20 +0530, Aditya Srivastava wrote:
> > > Presence of hexadecimal address or symbol results in false warning
> > > message by checkpatch.pl.
> > []
> > > diff --git a/scripts/checkpatch.pl b/scripts/checkpatch.pl
> > []
> > > @@ -3051,7 +3051,10 @@ sub process {
> > >  		}
> > >  
> > >  # check for repeated words separated by a single space
> > > -		if ($rawline =~ /^\+/ || $in_commit_log) {
> > > +# avoid false positive from list command eg, '-rw-r--r-- 1 root root'
> > > +		if (($rawline =~ /^\+/ || $in_commit_log) &&
> > > +		$rawline !~ /[bcCdDlMnpPs\?-][rwxsStT-]{9}/) {
> > 
> > Alignment and use \b before and after the regex please.
> 
> If we use \b either before or after or both it does not match patterns
> such as:
> +   -rw-r--r--. 1 root root 112K Mar 20 12:16'
selinux-policy-3.14.4-48.fc31.noarch.rpm

OK, thanks, it's good you checked.

> > []

> > What does all this code actually avoid?
> 
> Sir, there are multiple variations of hex for which this warning is
> occurring, for eg:
> 1) 00 c0 06 16 00 00 ff ff 00 93 1c 18 00 00 ff ff  ................
> 2) ffffffff ffffffff 00000000 c070058c
> 3)     f5a:       48 c7 44 24 78 ff ff    movq
> $0xffffffffffffffff,0x78(%rsp)
> 4) +    fe fe
> 5) +    fe fe   - ? end marker ?
> 6) Code: ff ff 48 (...)

So why not just match first with /^[0-9a-f]+$/i ?

Doesn't that match all the cases listed above?