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Date: Tue, 31 Aug 2004 08:28:19 +0200
From: Jens Axboe <axboe@suse.de>
To: Arjan van de Ven <arjanv@redhat.com>
Cc: Adrian Bunk <bunk@fs.tum.de>, Linus Torvalds <torvalds@osdl.org>,
       Andrew Morton <akpm@osdl.org>, Matt Mackall <mpm@selenic.com>,
       linux-kernel@vger.kernel.org
Subject: Re: What policy for BUG_ON()?
Message-ID: <20040831062815.GA2312@suse.de>
References: <20040830201519.GH12134@fs.tum.de> <1093897329.2870.11.camel@laptop.fenrus.com>
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On Mon, Aug 30 2004, Arjan van de Ven wrote:
> On Mon, 2004-08-30 at 22:15, Adrian Bunk wrote:
> > Let me try to summarize the different options regarding BUG_ON, 
> > concerning whether the argument to BUG_ON might contain side effects, 
> > and whether it should be allowed in some "do this only if you _really_ 
> > know what you are doing" situations to let BUG_ON do nothing.
> > 
> > Options:
> > 1. BUG_ON must not be defined to do nothing
> > 1a. side effects are allowed in the argument of BUG_ON
> > 1b. side effects are not allowed in the argument of BUG_ON
> > 2. BUG_ON is allowed to be defined to do nothing
> > 2a. side effects are allowed in the argument of BUG_ON
> > 2b. side effects are not allowed in the argument of BUG_ON
> 
> since you quoted me earlier my 2 cents:
> 1) I would prefer BUG_ON() arguments to not have side effects; its just 
> cleaner that way. (similar to assert)
> 
> 2) if one wants to compiel out BUG_ON, I rather alias it to panic() than
> to nothing.

I agree completely with that.

-- 
Jens Axboe