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Date: Sat, 7 Jun 1997 07:48:47 +1000
From: Bruce Evans <bde@zeta.org.au>
Message-Id: <199706062148.HAA16814@godzilla.zeta.org.au>
To: craig@gnofn.org, hackers@FreeBSD.ORG
Subject: Re: gcc -m486, gcc -O2
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>Is -m486 desireable/useful on various flavors of 586-class
>chips?  Specifically curious about AMD K5.

It is sometimes a pessimization on 486's and often a pessimization
on 586's.  `-m486 -malign-functions=2 -mailign-jumps=2 -malign-loops=2'
may be best on 586's.

>Is there any reason -O2 would not be a good idea for kernel/make
>world in make.conf?  I notice that the suggested use is -O2 for
>everything else and -O for the kernel.  

-O2 is sometimes a pessimization.  `-O2 -m486' was suggested in 1994.
It is wronger now.

Bruce