Date: Mon, 8 Sep 1997 08:12:12 +0800 (GMT)
From: Orlando Andico <orly AT dilnet DOT upd DOT edu DOT ph>
To: sime AT fly DOT cc DOT etf DOT hr
cc: djgpp AT delorie DOT com
Subject: Re: Optimization of math.h functions
In-Reply-To: <5uu8jp$fqf@bagan.srce.hr>
Message-ID: <Pine.SGI.3.93.970908081052.1721C-100000@gibson>
MIME-Version: 1.0
Content-Type: TEXT/PLAIN; charset=US-ASCII
Precedence: bulk

On 7 Sep 1997, S. Mikecin wrote:

..
> : Use '-ffast-math' to inline the math functions.
> 
> Yes, you're right. But it seems to work only for a few functions (sqrt, sin,
> cos, fabs). Compared to Watcom C 10.5a output which inlines almost all
> math functions (sqrt, sin, cos, fabs, tan, atan, sinh, cosh, log, exp,...) it
> is not as good as it should be (maybe in gcc 2.8.0?).

If I remember the GCC man page directly, there's a further caveat to be
aware of when using -ffast-math. That is, when this flag is used, GCC does
not guarantee that math error exceptions (matherr() et al) will be
completely ANSI compliant.

That said, I use -ffast-math all the time.  :)
 
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Orlando Alcantara Andico
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