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Date: Fri, 9 Jan 1998 12:31:16 -0500
From: Norman C Rice <nrice@emu.sourcee.com>
To: Yingjun He <hey@tuns.ca>
Cc: freebsd-questions@FreeBSD.ORG
Subject: Re: your mail
References: <3.0.1.32.19980109091508.00969330@newton.ccs.tuns.ca>
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On Fri, Jan 09, 1998 at 09:15:08AM +0000, Yingjun He wrote:
> Hello,
> 
> I am running FreeBSD2.25 and 2.05 and I found that the numerical calculation
> results of the same program is different. Is this caused by the difference of
> the operating systems? Or something wrong with my hardware?
> 
> Thank you. 
>          ______________________________________________
>         | Dr. Ian (Yingjun) He                         |
>       _ | Centre for Marine Vessel Design & Research   | _
>      / )| Dalhousie University, DelTech College        |( \
>     / / | Halifax, Nova Scotia, Canada B3J 2X4         | \ \
>   _( (_ |      Phone: (902)420-7975                    | _) )_
>  (((\ \>|_/-)  Fax  : (902)423-9734                (-\_|</ /)))
>  (\\\\ \_/ /________________________________________\ \_/ ////)
>   \       /    Email: hey@tuns.ca                    \       /
>    \    _/     WWW  : http://www.tuns.ca/~hey         \_    /
>    //////  ==========================================  \\\\\\

What hardware are you using on each system (processor and floating point unit)?
Are you using the same executable on both systems?
Are you using floating point emulation? 
What is the calculation?

If you are using floating point emulation, which type are you using on
each system? Here is an excerpt from the LINT kernel configuration
file from a FreeBSD 2.2.5-STABLE system.

#
# A math emulator is mandatory if you wish to run on hardware which
# does not have a floating-point processor.  Pick either the original,
# bogus (but freely-distributable) math emulator, or a much more
# fully-featured but GPL-licensed emulator taken from Linux.
#
options     MATH_EMULATE        #Support for x87 emulation
# Don't enable both of these in a real config.
options     GPL_MATH_EMULATE    #Support for x87 emulation via
                                #new math emulator
					 
-- 
Regards,
Norman C. Rice, Jr.