From mboxrd@z Thu Jan  1 00:00:00 1970
From: Thomas Monjalon <thomas.monjalon@6wind.com>
Subject: Re: 16.07-rc2 issue with rte_rtm_init(void) constructor
Date: Thu, 14 Jul 2016 13:30:14 +0200
Message-ID: <8960687.gEONPgFZ8H@xps13>
References: <C9B4A9F8-E6CB-4B5A-9472-6E2C4877C158@cisco.com>
 <2746154.p2WhExbrR9@xps13> <BCA60C52-9E53-45DE-908C-157A96DE06E8@cisco.com>
Mime-Version: 1.0
Content-Type: text/plain; charset="utf-8"
Content-Transfer-Encoding: quoted-printable
Cc: dev@dpdk.org
To: "Damjan Marion (damarion)" <damarion@cisco.com>
Return-path: <dev-bounces@dpdk.org>
Received: from mail-wm0-f51.google.com (mail-wm0-f51.google.com [74.125.82.51])
 by dpdk.org (Postfix) with ESMTP id 329633989
 for <dev@dpdk.org>; Thu, 14 Jul 2016 13:30:16 +0200 (CEST)
Received: by mail-wm0-f51.google.com with SMTP id i5so109273089wmg.0
 for <dev@dpdk.org>; Thu, 14 Jul 2016 04:30:16 -0700 (PDT)
In-Reply-To: <BCA60C52-9E53-45DE-908C-157A96DE06E8@cisco.com>
List-Id: patches and discussions about DPDK <dev.dpdk.org>
List-Unsubscribe: <http://dpdk.org/ml/options/dev>,
 <mailto:dev-request@dpdk.org?subject=unsubscribe>
List-Archive: <http://dpdk.org/ml/archives/dev/>
List-Post: <mailto:dev@dpdk.org>
List-Help: <mailto:dev-request@dpdk.org?subject=help>
List-Subscribe: <http://dpdk.org/ml/listinfo/dev>,
 <mailto:dev-request@dpdk.org?subject=subscribe>
Errors-To: dev-bounces@dpdk.org
Sender: "dev" <dev-bounces@dpdk.org>

2016-07-14 09:36, Damjan Marion:
>=20
> > On 14 Jul 2016, at 10:20, Thomas Monjalon <thomas.monjalon@6wind.co=
m> wrote:
> >=20
> > 2016-07-13 22:58, Damjan Marion:
> >> I have issues with linking application to 16.07-rc2.
> >>=20
> >> Looks like reason is constructor function in include file,
> >> so our unit test apps are failing to link as they are not linked w=
ith dpdk libs.
> >> (and they should not be as they are not calling any dpdk function)=
.
> >=20
> > I don't understand:
> > Why are you linking DPDK if you do not use any DPDK function?
>=20
> If i simplify it, i have 4 components:
>=20
> 1. libdpdk
> 2. libXXX
> 3. app-A
> 4. app-B
>=20
> libXXX includes some dpdk headers, mainly because of data structures =
like rte_mbuf, and some functions are calling
> functions form libdpdk.
>=20
> app-A links against libdpdk and libXXX
> app-B links against libXXX only and only uses functions from libXXX w=
hich doesn=E2=80=99t have dpdk dependency
>=20
> This is working fine in 14.04. In 14.07 rte_rtm_init() implants himse=
lf into libXXX as it is defined
> in header file, and that causes linking to fail due to missing rte_cp=
u_get_flag_enabled().

OK I better understand :)

> >> static inline void __attribute__((constructor))
> >> rte_rtm_init(void)
> >> {
> >>        rtm_supported =3D rte_cpu_get_flag_enabled(RTE_CPUFLAG_RTM)=
;
> >> }
> >>=20
> >> linking fails with:
> >> dpdk/include/rte_spinlock.h:103: undefined reference to `rte_cpu_g=
et_flag_enabled=E2=80=99
> >>=20
> >> Is there any chance that this one is moved to some .c file, so it =
is loaded
> >> only when it is really needed?
> >=20
> > Yes it could be moved to lib/librte_eal/common/arch/x86/.
>=20
> Any chance to get this in 16.07 ?

Yes maybe if you submit a patch quickly and it is clean enough.