From owner-cvs-all  Sat Oct 26 20:10:44 2002
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Date: Sun, 27 Oct 2002 14:21:38 +1100 (EST)
From: Bruce Evans <bde@zeta.org.au>
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To: Dag-Erling Smorgrav <des@ofug.org>
Cc: Poul-Henning Kamp <phk@critter.freebsd.dk>,
	John Baldwin <jhb@FreeBSD.org>, <cvs-all@FreeBSD.org>,
	<cvs-committers@FreeBSD.org>
Subject: Re: cvs commit: src/sys/kern kern_mutex.c
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On Sat, 26 Oct 2002, Dag-Erling Smorgrav wrote:

> Bruce Evans <bde@zeta.org.au> writes:
> > No need.  Memory access errors are very easy to debug since debuggers show
> > a context with the precise instruction and function that caused the error.
> > Anyone how can debug them doesn't need a hint about why the function might
> > cause a memory access error.  Panics are not so easy to debug, since the
> > context and restartability are messed up by calling panic().
>
> Maybe the KASSERT macros could be rewritten to cause a trap rather
> than call panic(), to avoid messing up the stack frame?
>
> #define KASSERT(exp,msg) \
>         do { if (!(exp)) panic_hint msg; *(int *)NULL = 0; } while (0)
>
> panic_hint() would be a short wrapper for vsnprintf().

Yes, though I would be tempted to optionally leave out the panic_hint part.

Bruce


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