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Date: Sat, 28 Aug 2004 12:58:16 -0700
From: Andrew Morton <akpm@osdl.org>
To: Adrian Bunk <bunk@fs.tum.de>
Cc: mrmacman_g4@mac.com, linux-kernel@vger.kernel.org
Subject: Re: [2.6 patch][1/3] ipc/ BUG -> BUG_ON conversions
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Adrian Bunk <bunk@fs.tum.de> wrote:
>
>  > Anything you put in BUG_ON() must *NOT* have side effects.
>  >...
> 
>  I'd have said exactly the same some time ago, but I was convinced by 
>  Arjan that if done correctly, a BUG_ON() with side effects is possible  
>  with no extra cost even if you want to make BUG configurably do nothing.

Nevertheless, I think I'd prefer that we not move code which has
side-effects into BUG_ONs.  For some reason it seems neater that way.

Plus one would like to be able to do

	BUG_ON(strlen(str) > 22);

and have strlen() not be evaluated if BUG_ON is disabled.

A minor distinction, but one which it would be nice to preserve.