Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) client-ip=23.128.96.18;
Message-ID: <38388294c6ad7bf4abdb1b9a0bac9af5224c8fa6.camel@klomp.org>
Subject: Re: Static call dependency on libelf version?
From:   Mark Wielaard <mark@klomp.org>
To:     Josh Poimboeuf <jpoimboe@redhat.com>
Cc:     peterz@infradead.org, Hugh Dickins <hughd@google.com>,
        linux-kernel@vger.kernel.org, x86@kernel.org
Date:   Tue, 15 Sep 2020 16:38:02 +0200
In-Reply-To: <20200915141701.j5fnir63trpwqbfp@treble>
References: <alpine.LSU.2.11.2009142337530.1550@eggly.anvils>
         <20200915093016.GV1362448@hirez.programming.kicks-ass.net>
         <d02d57308d9e8febd569c3fd3757dbcc87b1c4a1.camel@klomp.org>
         <20200915141701.j5fnir63trpwqbfp@treble>
Content-Type: text/plain; charset="UTF-8"
Content-Transfer-Encoding: 8BIT
Mime-Version: 1.0
Sender: linux-kernel-owner@vger.kernel.org
Precedence: bulk

Hi Josh,

On Tue, 2020-09-15 at 09:17 -0500, Josh Poimboeuf wrote:
> On Tue, Sep 15, 2020 at 01:24:17PM +0200, Mark Wielaard wrote:
> > But all this is for ancient versions of elfutils libelf. So it is hard
> > to say and my memory might be failing. If someone can confirm 0.158
> > (which is 6 years old) works fine I would pick that as minimum version,
> > otherwise simply go with 0.168 which is 4 years old and should be on
> > most systems by now.
> 
> I just discovered elf_version(), I assume that would allow us to check
> and enforce the libelf version?

No, sorry. That is for the ELF file format version, which is and has
always been  version 1 (and I suspect it will be for the next 20
years).

There is /usr/include/elfutils/version.h which provides a
_ELFUTILS_PREREQ(major, minor) macro if you need something during
compile time.

Note that in theory libelf is a generic library (there are variants for
Solaris and BSD with which we try to be [source] compatible), but the
only actively maintained version is the elfutils one.

Cheers,

Mark