linux-kernel - Re: InfiniBand-ocrdma: Delete unnecessary variable initialisations in 11 functions

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Date:	Fri, 15 Jan 2016 19:41:50 +0200
From:	Leon Romanovsky <leon@...n.nu>
To:	Bart Van Assche <bart.vanassche@...disk.com>
Cc:	SF Markus Elfring <elfring@...rs.sourceforge.net>,
	linux-rdma@...r.kernel.org,
	Devesh Sharma <devesh.sharma@...gotech.com>,
	Doug Ledford <dledford@...hat.com>,
	Hal Rosenstock <hal.rosenstock@...il.com>,
	Mitesh Ahuja <mitesh.ahuja@...gotech.com>,
	Sean Hefty <sean.hefty@...el.com>,
	Selvin Xavier <selvin.xavier@...gotech.com>,
	LKML <linux-kernel@...r.kernel.org>,
	kernel-janitors@...r.kernel.org,
	Julia Lawall <julia.lawall@...6.fr>
Subject: Re: InfiniBand-ocrdma: Delete unnecessary variable initialisations
 in 11 functions

On Fri, Jan 15, 2016 at 09:19:38AM -0800, Bart Van Assche wrote:
> On 01/15/2016 09:00 AM, Leon Romanovsky wrote:
> >On Fri, Jan 15, 2016 at 05:24:50PM +0100, SF Markus Elfring wrote:
> >
> >Since, you didn't answer to my original question, I will repeat it again.
> >[Q.] What did you try to achieve by this patch?
> 
> Hello Leon,
> 
> Have you noticed Dan's reply: "Doing bogus initializations turns off GCC's
> checking for uninitialized variables so it's a bad habit."

Yes and his second part of that message too, that uninitialized
checks in GCC work as not as expected [1, 2].

Stackoverflow site has a lot examples of these types of bugs [3].
These examples together with Dan's suggestion requires from all
reviewers to be extra cautions when removing variable initialization.

[1] https://gcc.gnu.org/wiki/Better_Uninitialized_Warnings
[2] https://gcc.gnu.org/bugzilla/buglist.cgi?quicksearch=may%20be%20uninitialized
[3] http://stackoverflow.com/questions/27063678/compiler-not-detecting-obviously-uninitialized-variable

> 
> Thanks,
> 
> Bart.
> --
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