From:	"John M. Aldrich" <fighteer AT cs DOT com>
Newsgroups:	comp.os.msdos.djgpp
Subject:	Re: ! Optimization in Practice
Date:	Fri, 03 Apr 1998 18:34:24 -0500
Organization:	Two pounds of chaos and a pinch of salt.
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Message-ID:	<35257200.2C7B@cs.com>
References:	<C12565DB DOT 003ACF44 DOT 00 AT vega DOT ads DOT it>
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To:	djgpp AT delorie DOT com
DJ-Gateway:	from newsgroup comp.os.msdos.djgpp

G DOT DegliEsposti AT ads DOT it wrote:
> 
> If this can explain why use -O2 in stead of -O3, I agree
> with you on one point: why -O1 in stead of -O2 ?
> Maybe the switch is available for backward compatibility ?

Each of the optimization levels takes progressively more time to
compile, and -O2 doesn't increase speed over -O1 by as much as -O1
increases speed over non-optimized code.  For myself, I always use -O2
in production code.  The various options exist for flexibility.  :-)

-- 
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|      John M. Aldrich       | "A committee is a life form with six |
|       aka Fighteer I       | or more legs and no brain."          |
|   mailto:fighteer AT cs DOT com   |                                      |
| http://www.cs.com/fighteer |                 - Lazarus Long       |
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