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Date: Fri, 28 May 2004 14:53:40 +1000
From: Paul Mackerras <paulus@samba.org>
To: Andreas Dilger <adilger@clusterfs.com>
Cc: David Gibson <david@gibson.dropbear.id.au>, Andrew Morton <akpm@osdl.org>,
       Anton Blanchard <anton@samba.org>, linux-kernel@vger.kernel.org,
       linuxppc64-dev@lists.linuxppc.org
Subject: Re: [PPC64] Remove silly debug path from get_vsid()
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Andreas Dilger writes:

> so presumably if you don't select CONFIG_PPCDBG it is also a no-op unless
> the compiler is broken and doesn't optimize away "if (0)" stanzas.  The
> original construct gives you the option to enable this particular debugging
> at runtime (without necessarily enabling all debugging at one time) if wanted.

And the effect of suddenly changing your VSID calculation algorithm in
mid-stream is pretty catastrophic.  There is no sensible reason
wanting to be able to turn this on and off at runtime.  This is not
just some extra checking.

Paul.