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Date:   Fri, 8 Jun 2018 01:45:34 +0200
From:   Luc Van Oostenryck <luc.vanoostenryck@gmail.com>
To:     Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc:     Kees Cook <keescook@chromium.org>, Miroslav Benes <mbenes@suse.cz>,
        LKML <linux-kernel@vger.kernel.org>
Subject: Re: sparse warnings in overflow.h
Message-ID: <20180607234533.nfdxd4cqiygahfms@ltop.local>
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On Thu, Jun 07, 2018 at 09:25:09PM +0200, Rasmus Villemoes wrote:
> 
> IIRC, the problem is that sparse pretends to be the gcc sparse itself
> was built with, which is obviously entirely unrelated to the C dialect
> that that particular sparse version groks. Sigh. Ack to the fix above.

Yes, indeed, and it is sometimes a problem.
Ideal would be that sparse would pretend to be same GCC as the one used
to compile the code being checked *and* to have exactly the same features.

Pretending to be an older version of GCC would maybe solve the present
problem it's not really a general solution.

One good thing would be to not depend on GCC versions to enable some
features (but GCC offers few facilities helping here).


Best regards,
-- Luc Van Oostenryck