From mboxrd@z Thu Jan  1 00:00:00 1970
From: Panu Matilainen <pmatilai@redhat.com>
Subject: Re: Can't compile DPDK if both
 CONFIG_RTE_BUILD_COMBINE_LIBS and LIBRTE_PMD_XENVIRT are set to "yes"
Date: Tue, 24 Nov 2015 15:57:02 +0200
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 <thiagocmartinsc@gmail.com>,
 dev@dpdk.org, Neil Horman <nhorman@tuxdriver.com>,
 "Gonzalez Monroy, Sergio" <sergio.gonzalez.monroy@intel.com>
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On 11/23/2015 08:37 PM, Martinx - =E3=82=B8=E3=82=A7=E3=83=BC=E3=83=A0=E3=
=82=BA wrote:
> Hello!
>
> My name is Thiago, I'm trying to compile DPDK 2.0, 2.1 and/or 2.2-rc1,
> on Ubuntu with Xen support but, it does not build...
>
> Also, initially, I'm using DPDK sources from Ubuntu APT repository
> but, it is also reproducible using upstream DPDK tarball as well,
> explained as follows:
>
> Problem:
>
> * It is not possible to use the following DPDK options at the same time=
:
>
> CONFIG_RTE_BUILD_COMBINE_LIBS
> LIBRTE_PMD_XENVIRT
>
> Ubuntu DPDK .deb package uses CONFIG_RTE_BUILD_COMBINE_LIBS and,
> without it, it can't build its .deb binary package (step: "make -f
> debian/rules binary" doesn't work).
>
> So, if you have the above two options set to "yes", the following
> error appear while building DPDK:
>
> http://pastebin.com/xUsQPxh8
>
[...]
> Build error:
>
> http://pastebin.com/fuUkpF4w
>
> If you remove "CONFIG_RTE_BUILD_COMBINE_LIBS", then, you can build it
> with "LIBRTE_PMD_XENVIRT", and vice-versa. But, without
> "...COMBINE_LIBS", Ubuntu .deb package doesn't get builded.
>
> BTW, the option LIBRTE_XEN_DOM0 is fine when also enabling COMBINE_LIBS=
...
>
> Am I missing something? Is this by design or a DPDK bug?

DPDK bug I would say. The combined library has been increasingly in risk=20
of collapsing under its own weight for some time now.

A much better way of achieving the same is using a so called linker=20
script which is essentially just an ascii file listing all the=20
individual libraries which the linker handles behind the scenes.
FWIW, that's how the combined library is packaged on Fedora and RHEL and=20
consumers like OVS and pktgen never knew the difference.

The linker script approach has been suggested before but somehow the=20
threads died without nothing actually happening. I'll revive the patch=20
and post here shortly. Unless Sergio (cc'd) who previously worked on the=20
patches has a newer version cooking silently?

P.S. I know, a "linker script" sounds exotic but they're actually rather=20
commonplace. On an average Linux system, libc.so is a linker script for=20
example.

	- Panu -