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Message-ID: <554EBBA5.9000303@ignoranthack.me>
Date: Sat, 09 May 2015 19:00:05 -0700
From: Sean Bruno <sbruno@ignoranthack.me>
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To: freebsd-hackers@freebsd.org
Subject: Re: How to get anything useful out of kgdb?
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Hash: SHA512


>> 
>> I'm guessing that the place to change -O2 -> -O0 is in
>> kern.pre.mk ?
>> 
>> sean
> 
> No, it means you need to iescover DEBUG and how it affects
> optimization level :)
> 
> .if defined(DEBUG) _MINUS_O=       -O CTFFLAGS+=      -g .else ...
> 
> Say, I have 'makeoptions     DEBUG="-g -gdwarf-2"' in my kernel
> config file. -gdwarf-2 is probably not required anymore.

Indeed!  :-)

I was directed to go a slightly different way:

make.conf:
COPTFLAGS=-O0
CFLAGS=-O0


This makes unbootable kernels and they panic unless you defined the
following in your kernel config:
options		KSTACK_PAGES=6


sean
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