linux-kernel - Re: [PATCH] compiler.h: don't use temporary variable in __compiletime

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <20140508065646.GF2844@laptop.programming.kicks-ass.net>
Date:	Thu, 8 May 2014 08:56:46 +0200
From:	Peter Zijlstra <peterz@...radead.org>
To:	Johannes Berg <johannes@...solutions.net>
Cc:	Andrew Morton <akpm@...ux-foundation.org>,
	linux-kernel@...r.kernel.org,
	Daniel Santos <daniel.santos@...ox.com>,
	"Paul E. McKenney" <paulmck@...ux.vnet.ibm.com>
Subject: Re: [PATCH] compiler.h: don't use temporary variable in
 __compiletime_assert()

On Thu, May 08, 2014 at 08:31:25AM +0200, Johannes Berg wrote:
> From: Johannes Berg <johannes.berg@...el.com>
> 
> Usually, BUG_ON and friends aren't even evaluated in sparse, but
> recently compiletime_assert_atomic_type() was added, and that now
> results in a sparse warning every time it is used.
> 
> The reason turns out to be the temporary variable, after it sparse
> no longer considers the value to be a constant, and results in a
> warning and an error. The error is the more annoying part of this
> as it suppresses any further warnings in the same file, hiding
> other problems.
> 
> Since this is all about compile time and the condition should be
> side-effect free to start with, there's no downside (apart maybe
> from a slight compilation time penalty?) to just duplicating it,
> leaving sparse able to evaluate it at check time, getting rid of
> the warning and error.
> 
> Signed-off-by: Johannes Berg <johannes.berg@...el.com>

Acked-by: Peter Zijlstra <peterz@...radead.org>
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/