Date: Wed, 10 May 2006 16:45:54 -0700
From: Andrew Morton <akpm@osdl.org>
To: Al Viro <viro@ftp.linux.org.uk>
Cc: davem@davemloft.net, dwalker@mvista.com, alan@lxorguk.ukuu.org.uk,
       linux-kernel@vger.kernel.org
Subject: Re: [PATCH -mm] sys_semctl gcc 4.1 warning fix
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Al Viro <viro@ftp.linux.org.uk> wrote:
>
> On Wed, May 10, 2006 at 04:05:48PM -0700, Andrew Morton wrote:
> > Sure - it's sad and we need some workaround.
> > 
> > The init_self() thingy seemed reasonable to me - it shuts up the warning
> > and has no runtime cost.  What we could perhaps do is to make
> > 
> > #define init_self(x) (x = x)
> > 
> > only if the problematic gcc versions are detected.  Later, if/when gcc gets
> > fixed up, we use
> 
> Sorry, no - it shuts up too much.  Look, there are two kinds of warnings
> here.  "May be used" and "is used".  This stuff shuts both.  And unlike
> "may be used", "is used" has fairly high S/N ratio.
> 
> Moreover, once you do that, you lose all future "is used" warnings on
> that variable.  So your ability to catch future bugs is decreased, not
> increased.

Only for certain gcc versions.  Other people use other versions, so it'll
be noticed.  If/when gcc gets fixed, more and more people will see the real
warnings.

Look, of course it has problems.  But the current build has problems too. 
It's a question of which problem is worse..
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