From: "S. Mikecin" <sime AT fly DOT cc DOT fer DOT hr>
Newsgroups: comp.os.msdos.djgpp
Subject: Re: Help - Floating Point Exception
Date: 26 Sep 1998 15:36:14 GMT
Organization: FER, Croatia
Lines: 48
Message-ID: <6uj1le$4dg$7@bagan.srce.hr>
References: <GoldED DOT 199809242144148700 DOT enlar AT hidespam DOT iname DOT com>
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Eneko Lacunza <enlar AT hidespam DOT iname DOT com> wrote:
: Hello All!

:     I'm having some problems with the following code:

: === Cut ===
: #define pi 3.1415926535897932385

: void build_table(void)
: {
: unsigned short xcont,ycont;
: float radio,angulo;

:      for(ycont=0;ycont<200;ycont++)
:          for(xcont=0;xcont<320;xcont++)
:          {
:              radio=sqrt((xcont-160)*(xcont-160)+(100-ycont)*(100-ycont));
:              angulo=atan2((xcont-160),(100-ycont));

:              table[xcont][ycont][0]=floor(radio);
:              table[xcont][ycont][1]=floor(255*angulo/(2*pi)); // FPE
:          }
: }
: === Cut ===

:     This crashes at the point noted as //FPE with a Floating Point
: exception. This is quite tricky, because it doesn't crash in a shell (i.e.
: running it under rhide) and if I try to redir the crash, redir crashes when 
: the program has finished the above code and is doing something else.

:     Could somebody tell me what does that exception mean, and how could I
: fix it (if this info is enough). I'm using GCC 2.7.2...

:     Any help would be appreciated.

If you're sure you have correct code, than this my help:

use:

#include <float.h>

and call _fpcontrol(MSW_EM,MSW_EM) at the beggining of main().

This will disable FPEs.

-- 

						<smikecin AT bigfoot DOT com>