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From: Duncan Sands <baldrick@wanadoo.fr>
To: "Martin J. Bligh" <mbligh@aracnet.com>, Andrew Morton <akpm@digeo.com>
Subject: Re: BUGed to death
Date: Tue, 15 Apr 2003 16:58:10 +0200
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> > No, I meant what happens if BUG() is non-trivial and BUG_ON is a no-op.
> > I thought it might give an indication of whether time was being lost
> > evaluating the condition (occurs with BUG and BUG_ON), or mispredicting
> > the branch (only occurs with BUG).
>
> Mmmm. wouldn't that just optimise away the BUG_ONs, but not the BUGs ?
> Which will tell you something, but I'm not sure anything interesting.
> My impression is that if I do:
>
> if (foo)
> 	do {} while (0);
>
> the compiler will just ditch the whole thing, and not evaluate foo.
> I'll admit to not having checked that, but still ....

Good point.  So much for trying to get info without converting a bunch
of BUG's into BUG_ON's...

Duncan.