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From: graichen@mail.physik.fu-berlin.de (Thomas Graichen)
Newsgroups: comp.unix.bsd.freebsd.misc
Subject: Re: Floating Point Exceptions
Date: 26 Feb 1996 07:58:17 GMT
Organization: his FreeBSD box :-)
Lines: 34
Message-ID: <4grp6p$kq@mordillo.physik.fu-berlin.de>
References: <4gqv91$r88@susscsc1.rdg.ac.uk>
NNTP-Posting-Host: lislip.physik.fu-berlin.de (130.133.3.126)
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Mark Blackman (markb) wrote:
: hello netland,
: ummm... what's the recommended way for getting a NaN value into
: a variable **without** causing a floating point exception?
: I want to use the NaN value as a marker for bad data and i thought
: a simple 0.0/0.0 would give me what i wanted, but alas a floating
: point exception was in the works. Is this a function of gcc,
: the kernel, the math coprocessor? and where do i tackle it?
you may try the following - it is'nt perfect but it works for me:
--- sys/i386/include/npx.h~ Tue Jan 3 04:57:46 1995
+++ sys/i386/include/npx.h Fri Aug 4 20:33:22 1995
@@ -138,7 +138,7 @@
#define __INITIAL_NPXCW__ __iBCS_NPXCW__
#endif
#else
-#define __INITIAL_NPXCW__ __BDE_NPXCW__
+#define __INITIAL_NPXCW__ __BETTER_BDE_NPXCW__
#endif
#ifdef KERNEL
after applying it you have to recompile your kernel
t
--
thomas graichen graichen@mail.physik.fu-berlin.de graichen@FreeBSD.org
perfection is reached, not when there is no longer anything to add, but when
there is no longer anything to take away antoine de saint-exupery