Gentoo Archives: gentoo-user

From: Volker Armin Hemmann <volker.armin.hemmann@××××××××××××.de>
To: gentoo-user@l.g.o
Subject: Re: [gentoo-user] gcc 4.2 and Core 2 Duo
Date: Fri, 20 Jul 2007 21:13:19
Message-Id: 200707202306.20669.volker.armin.hemmann@tu-clausthal.de
In Reply to: Re: [gentoo-user] gcc 4.2 and Core 2 Duo by Tobias Heinlein
1 On Freitag, 20. Juli 2007, Tobias Heinlein wrote:
2 > Volker Armin Hemmann wrote:
3 > > On Freitag, 20. Juli 2007, Andrew Gaydenko wrote:
4 > > march and mtune together? stupid.
5 > > mmmx, msse2, mss3 stupid. Its all part of nocona (maybe not msse3 but
6 > > everything else).
7 >
8 > Yes, that's right. These flags don't need to be set again. But there are
9 > some ebuilds that filter certain flags like march. By this filtering the
10 > package would be compiled without mmx and msse2 if the flags aren't set
11 > again. If they are, the package will still be compiled *with* mmx and
12 > msse2 even though march is filtered.. Yes, the filtering in the ebuild
13 > isn't done just for fun but some people still prefer to have mmx and
14 > msse2 enabled (when march is filtered).
15 > In short, settings these flags is not completley stupid but has a reason
16 > (even though it's not a very good one). :)
17
18
19 stupid is meant as 'uninformed' not imbecile in that case. But yes, choice of
20 words was not good in my part.
21
22 >
23 > > And then Os. That is a big nono.
24 >
25 > Why? I have a complete system running with -Os here and it's working fine.
26
27 because Os is known for miscompilations and it makes stuff slower a lot.
28
29 For example picture resizing in gwenview. Fast with O2, unbearable slow with
30 Os. Last tried with gcc 4.1 ;)
31 --
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