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From: "John Moran" <arronax@eircom.net>
To: "ILUG" <ilug@linux.ie>
Subject: RE: [ILUG] Optimizing for Pentium Pt.2
Date: Sat, 27 Jul 2002 17:10:39 +0100
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gcc, glibc and binutils, which the lfs site says not to optimise,
already determines what system you're compiling on, and optimises itself
to that. That's my understanding of how it works anyway.

John

Subject: Re: [ILUG] Optimizing for Pentium Pt.2


On Fri, Jul 26, 2002 at 11:24:30PM +0100, John Gay wrote:
> A while ago I asked what other packages I should optomize for Pentium.

> One
> person answered GlibC. This got me thinking about GCC itself, so I
asked on
> another list and got a few answers, most were "don't even think about
it" but
> a few suggested GCC and one pointed me to Linux From Scratch.

why?

or more specifically, what do you mean?  on one hand you can optimise
how gcc is compiled.  all that will do is make it generate the exact
same code just a smidge faster.  and since gcc is such a memory pig,
you'd do better to buy more ram to up your fs cache hits and to keep
gcc's heap out of swap.

on the other side you can look into patches to gcc that affect it's code
generation.  um, ok, but keep in mind that compiler errors suck. i can't
express that enough.  compilers should just work.  perfectly. always.
doing anything that might affect that is, in my opinion, insane. they're
hard to trace and you'd better have a deep knowledge of what's going on
to either report bugs to the patch developers or to fix it yourself.
plus my understanding is that gcc would need major changes to get large
speed boosts on x86 chips.

kevin




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