Gentoo Archives: gentoo-dev

From: Mike Gilbert <floppym@g.o>
To: Gentoo Dev <gentoo-dev@l.g.o>
Cc: x86@g.o, release@g.o
Subject: Re: [gentoo-dev] Gentoo i486 support
Date: Wed, 22 Aug 2018 14:30:51
In Reply to: [gentoo-dev] Gentoo i486 support by Ben Kohler
1 On Wed, Aug 22, 2018 at 8:26 AM Ben Kohler <bkohler@g.o> wrote:
2 >
3 > Hi guys,
4 >
5 > For some time now, we've been shipping broken i486 stage3s that do not
6 > run on pre-i686 hardware [1]. Due to a change in catalyst [2], we no
7 > longer set CXXFLAGS in the default make.conf, so the x86 profiles' (imho
8 > wrong/broken) defaults [3] kick in.
9 >
10 > I'd like to get this fixed, and I see 3 possible solutions, listed in
11 > order of my own preference:
12 >
13 > 1) Adjust x86 profile defaults to drop the problematic -march=i686.
14 > This would be more in line with amd64 profiles (et al), which set no
15 > -march value so it can run on any hardware for this arch.
17 Based on a quick test, running i686-pc-linuc-gnu-gcc without passing
18 -march seems to be equivalent to passing "-mtune=generic -march=i686".
19 So, you'll get code that will only run on i686, but has "generic"
20 tuning (whatever that means).
22 I don't think that will make a noticeable difference on user systems.
23 Most Gentoo people probably override this to some more specific CPU
24 model via CFLAGS in make.conf anyway.
26 So +1 from me on removing -march=i686 from the x86 arch profile.


Subject Author
Re: [gentoo-dev] Gentoo i486 support Thomas Deutschmann <whissi@g.o>