[From nobody Fri Oct 31 03:57:17 2008
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Message-ID: <3D494999.69DC08FE@attbi.com>
Date: Thu, 01 Aug 2002 10:45:45 -0400
From: Jim Houston <jim.houston@attbi.com>
Reply-To: jim.houston@attbi.com
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To: Dave Anderson <anderson@redhat.com>, kdb@oss.sgi.com
Subject: Re: [PATCH] oops on entry to kdb with gcc 3.1
References: <23430.1028205987@ocs3.intra.ocs.com.au>
	<3D493F93.3164F83F@redhat.com>
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Hi Dave, Keith,

Dave,  My patch should not be needed with gcc 2.96.  I have 
seen the oops in the kdba_setjmp when I had broken Makefiles.
In particular if the CONFIG_FRAME_POINTER should be controlling
the -fomit-frame-pointer option.  If you are using -fomit-frame-pointer
then CONFIG_FRAME_POINTER should not be defined.

We just started building kernels with gcc 3.1 from the 
RedHat 8.0 beta and thats where we started seeing the
problem I described.  I like the idea of the compiler
getting rid of the frame pointer save for leaf functions
so I hope we can solve this.

Keith,  I just tried my version of setjmp with an old
egcs-2.91.66 and you are correct that it is broken.  I will 
try to figure out when this was fixed.  I wonder if
its broken the same way in all the older compilers?  I could
do an explicit save of ebp and use it if __builtin_frame_address
returns trash.  Sigh.


Jim Houston - Concurrent Computer Corp.
]