Gentoo Archives: gentoo-dev

From: Davide Pesavento <pesa@g.o>
To: gentoo-dev@l.g.o
Cc: blueness@g.o, "Michał Górny" <mgorny@g.o>
Subject: Re: [gentoo-dev] multilib and different CFLAGS for 32 and 64bit ABIs
Date: Sun, 29 Mar 2015 21:29:12
Message-Id: CADfzvvYgP+prhsnpVUgAzo-deVhJi=xmfQoXb4yZa3ZhjQq1mg@mail.gmail.com
In Reply to: Re: [gentoo-dev] multilib and different CFLAGS for 32 and 64bit ABIs by Matthias Schwarzott
1 On Sun, Mar 29, 2015 at 9:12 PM, Matthias Schwarzott <zzam@g.o> wrote:
2 > On 29.03.2015 20:58, Matthias Schwarzott wrote:
3 >> Hi there!
4 >>
5 >> I updated my ~amd64 system recently to new hardware (Intel Core i3-4160).
6 >> Since then valgrind did no longer work for 32bit programs because
7 >> "-march=native" did choose instructions that valgrind does not support
8 >> in 32bit mode (even ld.so was unusable).
9 >>
10 >> After some research I put this into make.conf and now it works:
11 >> CFLAGS_x86="${CFLAGS_x86} -mno-avx2 -mno-sse4 -mno-bmi -mno-bmi2"
12 >> CXXFLAGS_x86="${CXXFLAGS_x86} -mno-avx2 -mno-sse4 -mno-bmi -mno-bmi2"
13 >>
14 >> Is this the best solution to the problem?
15 >> If yes, the valgrind ebuild could suggest something like this.
16 >> Either always show it or check cpu-flags first (is this maintainable?).
17 >>
18 > I should add, that it seems to break for exactly one package: mariadb
19 >
20
21 Not only mariadb, there are other known breakages... see
22 https://bugs.gentoo.org/show_bug.cgi?id=541616#c5
23
24 According to mgorny (Cc'ed):
25 "You are not supposed to touch CFLAGS_x86, ever. That's some magic
26 stuff that's used in profiles & multilib.eclass."
27
28 Regards,
29 Davide

Replies

Subject Author
Re: [gentoo-dev] multilib and different CFLAGS for 32 and 64bit ABIs Matthias Schwarzott <zzam@g.o>