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From: Jimi Xenidis <jimix@watson.ibm.com>
Subject: Re: [POWERPC] mark BUG() as noreturn
Date: Thu, 21 Sep 2006 08:18:47 -0400
To: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: ppc-dev <linuxppc-dev@ozlabs.org>, paulus@samba.org,
	Hollis Blanchard <hollisb@us.ibm.com>
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On Sep 21, 2006, at 12:55 AM, Stephen Rothwell wrote:

> From an idea from Michael Ellerman.
>
> We finish the BUG() macro with a call to a function marked with  
> attribute
> "noreturn" so that the compiler will know that BUG() and BUG_ON()
> (with a constant, non-zero argument) will not return.

But BUG() _can_ return, if I have a probe, xmon or kgdb configured it  
is possible  to play with the state of the world and try to continue/ 
recover, (xmon "x" command).  IMHO, this is a powerful debugging  
scenario.

Why are we concerned with the performance of this anyway?

-JX