Message-Id: <9805250826.AA23178@axe.bre.da>
Subject: Re: Code to Fix sinh() in libm.a / Floating Exceptions
To: eliz AT is DOT elta DOT co DOT il (Eli Zaretskii)
Date: Mon, 25 May 1998 10:26:52 METDST
Cc: djgpp AT delorie DOT com
In-Reply-To: <Pine.SUN.3.91.980524193551.12971M-100000@is>; from "Eli Zaretskii" at May 24, 98 7:36 pm
From: Jens Bischoff <j DOT bischoff AT airbus DOT dasa DOT de>
Precedence: bulk

Hello!

> > In fact, I prefer that the program terminate with a FP exception, so
> > that I am forced to fix the bug
> 
> This option will always be there: just set up x87 to generate
> exceptions by calling `_control87' at the beginning of `main'.
> 
> However, ANSI Standard specifically says that a program should NOT
> crash when exceptional numerical values are produced.  So I think the
> *default* behavior cannot be to generate SIGFPE.
> 

This may be a little bit off-topic (and to complicate to implement),
but for this problem (turning floating point exceptions on or off?)
I have a suggestion:

Would it be a possible (and good) sulution to switch on floating 
point exceptions via linker flags?
On this machine I use floating exceptions normally turned off,
but you can tell the linker to enable them via the +FP option.
For example: +FPO turns on exceptions on floating point overflow,
+FPU on underflow, and so on.
The linker has to generate the appropriate startup code then.

Jens

--
|      |      | Jens Bischoff   |   Daimler-Benz Aerospace Airbus |
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|      |      | Aerodynamic Data Department (EFD)                 |
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