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From: Detlev Zundel <dzu@denx.de>
To: joakim.tjernlund@transmode.se
Subject: Re: Signal backtrace function
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Date: Tue, 15 Apr 2008 17:50:45 +0200
In-Reply-To: <1208190010.5911.15.camel@gentoo-jocke.transmode.se> (Joakim
	Tjernlund's message of "Mon, 14 Apr 2008 18:20:09 +0200")
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Hi Jocke,

> On Mon, 2008-04-14 at 18:09 +0200, Detlev Zundel wrote:
>> Hi Jocke,
>> 
>> > I made my own backtrace function for printing
>> > a trace from within a signal handler. Maybe it
>> > can be useful for the kernel too? General
>> > comments welcome.
>> 
>> Probably a dumb question, but doesn't backtrace(3) from glibc work
>> architecture independent already?   Why do you need to reimplement it?
>
> Nope, it doesn't give you a good backtrace from within a signal handler.
> On x86 you can use the normal backtrace function with a minor
> workaround, but as ppc doesn't save a FP in leaf functions, that
> workaround does not work well. You can read more about it
> at http://www.linuxjournal.com/article/6391

Thanks for clearing that up.  I wasn't aware of that limitation.

Cheers
  Detlev

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