Re: [dpdk-dev] [PATCH] service: clean references to removed symbol

From: David Marchand <david.marchand@redhat.com>
To: "Van Haaren, Harry" <harry.van.haaren@intel.com>
Cc: "dev@dpdk.org" <dev@dpdk.org>,
	"stable@dpdk.org" <stable@dpdk.org>, Ray Kinsella <mdr@ashroe.eu>,
	 Neil Horman <nhorman@tuxdriver.com>,
	Dodji Seketeli <dodji@redhat.com>
Subject: Re: [dpdk-dev] [PATCH] service: clean references to removed symbol
Date: Thu, 8 Apr 2021 16:04:54 +0200	[thread overview]
Message-ID: <CAJFAV8zQOL-O_qLJvOtWsqMnWZeNR_7Dh8kE73FJxzYKXO48UQ@mail.gmail.com> (raw)
In-Reply-To: <BYAPR11MB3143B5EF130FFE371BCD61BBD7749@BYAPR11MB3143.namprd11.prod.outlook.com>

On Thu, Apr 8, 2021 at 3:08 PM Van Haaren, Harry
<harry.van.haaren@intel.com> wrote:
> > > For rte_service.h doc changes I'm all fine.
> > >
> > > For ABI consistency, this removes a function from the DPDK_21 version map that
> > didn't exist in
> > > the shared object itself. I'm not sure if that's an ABI break or not... I see ABI
> > experts on CC,
> > > and will let them comment on that topic.
> >
> > The symbol is not in the API anymore.
> > Applications can't have a reference to this symbol without a definition.
>
> Agreed, however I'm not familiar enough with linking/ABI stability to
> know if removing a symbol (even when not available in the API) could
> affect the resulting shared object's ABI.

After a discussion with Dodji and looking at binutils, I understand
that the versioning is applied for each symbol found in an elf object.
So at least with binutils, non-existent nodes in a version script are
harmless and have no impact on the generated elf.

-- 
David Marchand