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Date: Fri, 15 Jan 2016 17:09:35 +0200
From: Leon Romanovsky <leon@leon.nu>
To: SF Markus Elfring <elfring@users.sourceforge.net>
Cc: linux-rdma@vger.kernel.org, Devesh Sharma <devesh.sharma@avagotech.com>,
        Doug Ledford <dledford@redhat.com>,
        Hal Rosenstock <hal.rosenstock@gmail.com>,
        Mitesh Ahuja <mitesh.ahuja@avagotech.com>,
        Sean Hefty <sean.hefty@intel.com>,
        Selvin Xavier <selvin.xavier@avagotech.com>,
        LKML <linux-kernel@vger.kernel.org>, kernel-janitors@vger.kernel.org,
        Julia Lawall <julia.lawall@lip6.fr>
Subject: Re: InfiniBand-ocrdma: Delete unnecessary variable initialisations
 in 11 functions
Message-ID: <20160115150935.GA32346@leon.nu>
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On Fri, Jan 15, 2016 at 03:50:27PM +0100, SF Markus Elfring wrote:
> >> The variable "status" will be set to an appropriate value a bit later.
> >> Thus omit the explicit initialisation at the beginning.
> > 
> > What did you try to achieve by this patch?
> 
> I would like to optimise the affected source files a bit.
> Would you like to clarify any measurable effects around the implementation
> detail when various variables will only be initialised immediately
> before they will be read again?

Compiler will drop this variable initialization by itself because
there are no reads between this variable initialization and write.

I recommend you to take a look on the assembly code and ensure it
by yourself.

The proposed change won't affect performance at all.

> 
> Regards,
> Markus