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From: "Drokin, Oleg" <oleg.drokin@intel.com>
To: Joe Perches <joe@perches.com>
CC: Julia Lawall <julia.lawall@lip6.fr>,
        Dan Carpenter <dan.carpenter@oracle.com>,
        Andrew Morton <akpm@linux-foundation.org>,
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        "<linux-kernel@vger.kernel.org>" <linux-kernel@vger.kernel.org>,
        "Andy Whitcroft" <apw@canonical.com>
Subject: Re: [PATCH] checkpatch: Warn on macros with flow control statements
Thread-Topic: [PATCH] checkpatch: Warn on macros with flow control statements
Thread-Index: AQHPzG4AtdGxJRLQ1EGIjgHETNmIL5v6gvcAgABXSoCAAALvgIAACJAAgAAEgYA=
Date: Wed, 10 Sep 2014 14:52:47 +0000
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Hello!

On Sep 10, 2014, at 10:36 AM, Joe Perches wrote:

> On Wed, 2014-09-10 at 16:06 +0200, Julia Lawall wrote:
>> On Wed, 10 Sep 2014, Joe Perches wrote:
>>> On Wed, 2014-09-10 at 11:43 +0300, Dan Carpenter wrote:
>>>> On Tue, Sep 09, 2014 at 01:38:13PM -0700, Joe Perches wrote:
>>>>> Macros with flow control statements (goto and return) are
>>>>> not very nice to read as any flow movement is unexpected.
>>> 
>>> break and continue are also flow control statements
>>> but are those are frequently used in macros in
>>> complete switch statements so were not added.
>> 
>> Would it be possible to make a warning when there is a break or continue
>> but no while/switch/etc.
> 
> I suppose the has_flow_statement could be extended.
> 
> Maybe something like:
> 
> 			if ($ctx =~ /\b(goto|return|break|continue)\b/ &&
> 			    $ctx !~ /\b(switch|if|do|while)\b/) {
> 				has_flow_statement = 1;
> 			}
> 
> but checkpatch isn't really capable  of doing proper
> flow logic analysis.

While possibly not really suitable in checkpatch, it might be a good addition to
some static code analyzer as a "future bugs possible due to this" check.

Bye,
    Oleg