Subject: Re: New Defects reported by Coverity Scan for PostgreSQL
To: emre@hasegeli.com, Tom Lane <tgl@sss.pgh.pa.us>
Cc: Ning Yu <nyu@pivotal.io>, Alvaro Herrera <alvherre@2ndquadrant.com>,
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From: Tomas Vondra <tomas.vondra@2ndquadrant.com>
Message-ID: <611f2223-cf96-b26b-a58e-f8b76b156780@2ndquadrant.com>
Date: Thu, 2 Aug 2018 11:43:45 +0200
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On 08/01/2018 04:07 PM, Emre Hasegeli wrote:
>> I think there are three different things that need to be addressed:
>>
>> * Underspecified comments.
> 
> I agree.  My patch added comments, the next one with actual fixes adds
> more.  I just didn't want to invest even more time on them while the
> code is its current shape.
> 
>> * The function names and argument names are badly chosen IMO, because even
>> granted a convention such as the above, it's not very obvious what roles
>> "l1" and "l2" play.  I'm not exactly sure what would be better, but if you
>> used names like "ofseg" and "otherseg" you'd at least be trying.  I'd go
>> with an asymmetrical function name too, to make miswriting of calls less
>> likely.
> 
> Good idea.  I haven't though about that, but now such names makes more
> sense to me.  I will prepare another patch to improve the naming and
> comments to be applied on top of my current patches.
> 
>> * And lastly, are we sure there aren't actual *bugs* here?  I'd initially
>> supposed that lseg_closept_lseg acted as Emre says above, but reading the
>> code makes me think it's the other way around.  Its first two potential
>> assignments to *result are definitely assigning points on l2 not l1.
> 
> Yes, it is wrong beyond understanding.  The committed patch intended
> to keep answers as they were.  The next one actually fixes those.
> 

OK, so I think we should not do anything about the issues reported by 
coverity until we commit all the patches. Which may resolve some of 
those (pre-existing) issues, for example.

regards

-- 
Tomas Vondra                  http://www.2ndQuadrant.com
PostgreSQL Development, 24x7 Support, Remote DBA, Training & Services