From: sime AT fly DOT cc DOT fer DOT hr (S. Mikecin)
Newsgroups: comp.os.msdos.djgpp
Subject: Re: Floating point exception problem
Date: 9 May 1997 10:17:48 GMT
Organization: FER, Croatia
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References: <336ECFF0 DOT 1DEF AT netvision DOT net DOT il>
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To: djgpp AT delorie DOT com
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Guy Rauscher (rauscher AT netvision DOT net DOT il) wrote:
: Hi!

: I've constructed a small library for easily creating 3d applications with
: Allegro. I've produced a small program to demonstrate the functionality
: of my library and it ackwardly breaks sometimes due to a floating point
: exception. The real problem is that the exception occurs when the 3d
: clipping function is used but sometimes when I run the program, it works
: fine. This is NOT because the condition that causes the exception gets
: randomly unencountered. The clipping function uses floating point
: division.

: What I'd like to know is: what is it that causes a FPE in the first place
: and more specifically, what can I do to fix my program? If necessary,
: I'll post the source code.

I think this could solve your problem:

At the beggining of the program put:

#include <float.h>

and in the beggining of the main():

  _control87(MSW_EM,MSW_EM);



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