From: Thomas Demmer <demmer AT LSTM DOT Ruhr-UNI-Bochum DOT De>
Newsgroups: comp.os.msdos.djgpp
Subject: Re: Floating Point Exceptions ???
Date: Wed, 24 Sep 1997 14:10:28 +0200
Organization: Lehrstuhl fuer Stroemungsmechanik
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The NiBBLeR wrote:
> 
> Hello,
> 
> I've got a little problem:
> I'm writing a 3d-engine, and I'm using floating point...
> what can be wrong if I get a Floating Point Exception ???(Note: I don't
> divide)
> Can somebody please tell what the reason could be ???

After taking a deep breath, relaxing into the infinity of the universe
and gathering all my pscychokinetic forces I came up with the following
answer:
 It could be
 - mixing %f and %lf in ?scanf()
 - a dangling pointer pointing some integer or character that,
   when seen as a float, makes only little, if any, sense.
 - an old libm.a that has the bug in exp()
 - virtually anything that may go wrong in programming.

My advice:
 Compile everything with -g (yes, it is for the weak, but sometimes
 helps), run the program and try to figure out with symify why it
 crashes when. 

 Compile with -Wall and -pedantic and try to resolve each and every
 warning (Yeah, this is for them Pascal whimps, but sometimes
 really helps)

 Add some information or code snippets that exhibits the problem.
 My (and probably most people's) programming capabilities outperform
 my seer's capabilities. So we'd have half a chance to say something
 reasonable ;-)

-- 
Ciao
Tom

*************************************************************
* Thomas Demmer                                             *
* Lehrstuhl fuer Stroemungsmechanik                         *
* Ruhr-Uni-Bochum                                           *
* Universitaetsstr. 150                                     *
* D-44780  Bochum                                           *
* Tel: +49 234 700 6434                                     *
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* http://www.lstm.ruhr-uni-bochum.de/~demmer                *
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