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Mail Archives: djgpp/2000/04/02/11:53:38

Date: Sun, 2 Apr 2000 15:40:10 +0600 (LKT)
From: Kalum Somaratna aka Grendel <kalum AT lintux DOT cx>
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To: Eli Zaretskii <eliz AT is DOT elta DOT co DOT il>
cc: djgpp AT delorie DOT com
Subject: Re: EXE files too big!
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On Sun, 2 Apr 2000, Eli Zaretskii wrote:

 
> On Tue, 28 Mar 2000, Kalum Somaratna aka Grendel wrote:
> 
> > IMHO the -O3 switch is even better, as it provides better optimisations,
> > and I still have to tun into any problems with it being likely to
> > introduce optimiser errors into the code.
> 
> In my experience, -O3 produces slower code in most real-life
> programs.  

This maybe because of the inlining done by GCC overflowing the CPU cache.

>It certainly produces larger programs.  

I agree. This most probably is due to gcc inlining certain code sequences.
But since GNU programs run under the assumption that they are run on
memory abundant machines I suppose that this "larger program size" is not
that much relevant now. Especially with the current machines coming with
at least 64MB RAM..

>I always use -O2 by default.

The allegro library is one exception that comes to my mind. It uses the
-O3 for its default build. But I agree that most packages use the -O2
option.


Grendel


Hi, I'm a signature virus. plz set me as your signature and help me spread
:)


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