From owner-freebsd-alpha@FreeBSD.ORG  Thu Jan 13 15:17:36 2005
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Date: Thu, 13 Jan 2005 16:17:31 +0100
From: Idar Tollefsen <idart@performancedesign.no>
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To: Angus MacGyver <macgyver@calibre-solutions.co.uk>
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cc: freebsd-alpha@freebsd.org
Subject: Re: Question... Alpha Compile optimizations....
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Angus MacGyver wrote:
> I am just wondering, after reading the sample make.conf from
> 5.3-RELEASE, what is the nature of the bugs that MAY appear if I use 
> CFLAGS= -O2 -pipe
> as the optimisation flags.

Wasn't the -O2 problem fixed in GCC 3.x? Although I can't remember what 'x'...

> I have done so before on a 4.9 system, and have not experienced any
> problem that i could see, tho I did see an improvement in the speed of
> the resultant system (always a good thing)

I tried to compile the kernel with -O2 once on a 4.8 system. It booted, but 
didn't run for long before stopping, spawning messages about waiting for some 
lock (I don't remember the exact message).


- IT