From mboxrd@z Thu Jan  1 00:00:00 1970
Return-Path: <sourceware-bugzilla@sourceware.org>
Received: by sourceware.org (Postfix, from userid 48)
 id 3F199385F011; Wed, 15 Apr 2020 07:07:05 +0000 (GMT)
DKIM-Filter: OpenDKIM Filter v2.11.0 sourceware.org 3F199385F011
From: "marxin.liska at gmail dot com" <sourceware-bugzilla@sourceware.org>
To: elfutils-devel@sourceware.org
Subject: [Bug general/24498] 0.176: isn't LTO ready
Date: Wed, 15 Apr 2020 07:07:05 +0000
X-Bugzilla-Reason: CC
X-Bugzilla-Type: changed
X-Bugzilla-Watch-Reason: None
X-Bugzilla-Product: elfutils
X-Bugzilla-Component: general
X-Bugzilla-Version: unspecified
X-Bugzilla-Keywords: 
X-Bugzilla-Severity: normal
X-Bugzilla-Who: marxin.liska at gmail dot com
X-Bugzilla-Status: NEW
X-Bugzilla-Resolution: 
X-Bugzilla-Priority: P2
X-Bugzilla-Assigned-To: unassigned at sourceware dot org
X-Bugzilla-Target-Milestone: ---
X-Bugzilla-Flags: 
X-Bugzilla-Changed-Fields: 
Message-ID: <bug-24498-10460-YwNT4ImMgO@http.sourceware.org/bugzilla/>
In-Reply-To: <bug-24498-10460@http.sourceware.org/bugzilla/>
References: <bug-24498-10460@http.sourceware.org/bugzilla/>
Content-Type: text/plain; charset="UTF-8"
Content-Transfer-Encoding: quoted-printable
X-Bugzilla-URL: http://sourceware.org/bugzilla/
Auto-Submitted: auto-generated
MIME-Version: 1.0
X-BeenThere: elfutils-devel@sourceware.org
X-Mailman-Version: 2.1.29
Precedence: list
List-Id: Elfutils-devel mailing list <elfutils-devel.sourceware.org>
List-Unsubscribe: <http://sourceware.org/mailman/options/elfutils-devel>,
 <mailto:elfutils-devel-request@sourceware.org?subject=unsubscribe>
List-Archive: <https://sourceware.org/pipermail/elfutils-devel/>
List-Help: <mailto:elfutils-devel-request@sourceware.org?subject=help>
List-Subscribe: <http://sourceware.org/mailman/listinfo/elfutils-devel>,
 <mailto:elfutils-devel-request@sourceware.org?subject=subscribe>
X-List-Received-Date: Wed, 15 Apr 2020 07:07:05 -0000

https://sourceware.org/bugzilla/show_bug.cgi?id=3D24498

--- Comment #11 from Martin Li=C5=A1ka <marxin.liska at gmail dot com> ---
(In reply to kloczek from comment #10)
> > I would add a configure option --enable-lto that will append -flto to {=
C,LD}FLAGS.
>=20
> Please don't do that.
>=20
> LTO can be driven using only env variable.
>=20
> % CFLAGS=3D"<clto_cflags>" LDFLAGS=3D"<lto_ldflags>" ./configure

Works for me.

>=20
> Please use KISS principle and do not implement something which can be
> already done other way *without* touching existing code.
>=20
> PS. Changing {C,LD}FLAGS is not only part of using LTO. You need to pass =
NM,
> RANLIB and AR env variables.

Not necessarily. Typical Linux systems, like openSUSE, utilize auto-loading
mechanism of LTO plugins:

$ strace -f -s512 nm foo.o 2>&1 | grep plugin
...
openat(AT_FDCWD, "/usr/bin/../bin/../lib/bfd-plugins/liblto_plugin.so.0.0.0=
",
O_RDONLY|O_CLOEXEC) =3D 5

--=20
You are receiving this mail because:
You are on the CC list for the bug.=