Gentoo Archives: gentoo-user

From: Volker Armin Hemmann <volker.armin.hemmann@××××××××××××.de>
To: gentoo-user@l.g.o
Subject: Re: [gentoo-user] cpu flags / USE flags / compiler flags
Date: Wed, 31 Aug 2005 18:50:06
Message-Id: 200508312044.05668.volker.armin.hemmann@tu-clausthal.de
In Reply to: Re: [gentoo-user] cpu flags / USE flags / compiler flags by Mark Knecht
1 On Wednesday 31 August 2005 19:21, Mark Knecht wrote:
2 > On 8/31/05, Volker Armin Hemmann <volker.armin.hemmann@××××××××××××.de>
3 wrote:
4 > > Hi,
5 > >
6 > > before you panic, have you tried the firefox-bin packet with the same
7 > > site?
8 > >
9 > > Maybe nspluginviewer is the culprit? I had to kill it so many times I
10 > > can't remember.
11 >
12 > Thanks Volker. I'll give it a try.
13 >
14 > I'm still interested in the right way to really set up these flags
15 > though. I was looking at some of the online docs and found stuff like
16 > this in some emails:
17 >
18 > "I'm compiling currently with -mfpmath=387 -msse -mcpu=pentium3
19 > -march=pentium3 and gcc 3.1.1-4 from the very latest experimental
20 > cygwin distribution."
21 >
22 > Obviously I'm not intested in cygwin, etc., but when I saw -msse it
23 > made me wonder if I was supposed to change my CFLAGS line from
24 >
25 > CFLAGS="-O2 -march=pentium4 -pipe -fomit-frame-pointer"
26 >
27 > to
28 >
29 > CFLAGS="-O2 -march=pentium4 -pipe -fomit-frame-pointer -mmx -msse -msse2"
30 >
31 > I understand that the USE flags control what options are built into a
32 > pachage, but in the case of CPU flags do they also control the
33 > compiler flags that are used to build the package? Not being a
34 > programmer this is one part I'm confused about.
35 >
36
37 AFAIK the CFLAGS ONLY control the optimiziation, while the USEFLAGS only
38 control the configuration - if somebody built in some optimiziation for
39 mmx/sse, fine, this would be 'activated' by the useflags, not the cflags.
40
41 hm, about your CFLAGs, I suppose, -march=pentium4 already sets them (mmx/sse),
42 but this is something easily found in man gcc ;)
43 --
44 gentoo-user@g.o mailing list

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Re: [gentoo-user] cpu flags / USE flags / compiler flags capsel <capsel@×××××.com>