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To: Nate Williams <nate@mt.sri.com>
cc: Mike Smith <mike@smith.net.au>, shimon@simon-shapiro.org,
        freebsd-current@FreeBSD.ORG
Subject: Re: Compiler Bug??? 
In-reply-to: Your message of "Tue, 25 Nov 1997 08:16:09 PDT."
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Date: Wed, 26 Nov 1997 10:01:33 +1030
From: Mike Smith <mike@smith.net.au>
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> > > Guess what, you have bad memory!  Seriously, this is not a compiler bug,
> > > but something in your hardware that is hosed up.  Either the memory is
> > > bad, the timings are bad, the cache is bad, or some combination of the
> > > above is bad.  Compiler bugs don't go away on reboots, but corrupted
> > > memory does.
> > 
> > ... just to clarify here, as I am reading Simon slightly differently 
> > from you;
> > 
> >  - code built while running UP works.
> >  - code built while running SMP fails.
> 
> Actually, code built while running SMP was failing, but causing a boot
> into UP caused it to work, and then going back to SMP caused it to still
> work.

Not exactly.  I quote:

] Scenario 1:
]
] Xfmail of 17-Nov-97 with xforms 0.88:  Compiles fine, then produces
] dozens of ``Bad Attribute'' and `Bad Coordinates''.  These come from
] libX11.  Tearing my hair out did not help, so I boot UP (was on SMP).
] The problem is... GONE!
]
] Recompile on UP, reboot SMP...   Problem is...  Yup, GONE!

This is actually:

 - code built while running SMP fails while running SMP.
 - code built while running SMP works UP.
 - code built while running UP works everywere.

Either of our interpretations could be right.  More data, Simon?

mike