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Date:   Fri, 15 Nov 2019 01:38:21 +0100
From:   Luc Van Oostenryck <luc.vanoostenryck@gmail.com>
To:     Alex Kogan <alex.kogan@oracle.com>
Cc:     kbuild test robot <lkp@intel.com>, linux-sparse@vger.kernel.org,
        kbuild-all@lists.01.org, linux@armlinux.org.uk,
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        linux-arch@vger.kernel.org, linux-arm-kernel@lists.infradead.org,
        linux-kernel@vger.kernel.org, tglx@linutronix.de, bp@alien8.de,
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        daniel.m.jordan@oracle.com, dave.dice@oracle.com,
        rahul.x.yadav@oracle.com
Subject: Re: [PATCH v6 3/5] locking/qspinlock: Introduce CNA into the slow
 path of qspinlock
Message-ID: <20191115003821.raskzlj7hscz7vax@ltop.local>
References: <20191107174622.61718-4-alex.kogan@oracle.com>
 <201911110540.8p3UoQAR%lkp@intel.com>
 <58623E4A-973B-46CC-8FA8-29E68DB5EFF4@oracle.com>
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On Thu, Nov 14, 2019 at 03:57:34PM -0500, Alex Kogan wrote:
> + linux-sparse mailing list
> 
> It seems like a bug in the way sparse handles “pure” functions that return
> a pointer.

Yes, it's a bug in sparse.
 
> The warnings can be eliminated by adding an explicit cast, e.g.:
> 
> 	node = (struct mcs_spinlock *)grab_mcs_node(node, idx);
> 
> but this seems wrong (unnecessary) to me.

Indeed, it would be wrong.

Thanks for analyzing and reporting this,
-- Luc