Re: [PATCH] change GLIBC PPC64/ELF2 ABI default to 2.17

["Carlos O'Donell" <carlos at redhat dot com>]

On 01/31/2014 04:46 PM, H.J. Lu wrote:
> On Fri, Jan 31, 2014 at 1:37 PM, Jeff Law <law@redhat.com> wrote:
>> On 01/31/14 12:24, Brooks Moses wrote:
>>>
>>>
>>> My assumption at this point is that there is _no_ such purely technical
>>> argument.  Carlos and Jeff have implied that RedHat's team is under
>>> constraints that would prohibit doing so, and have implied that these
>>> are for "management" reasons rather than "technical" reasons.  As I have
>>> no connection to their team, I am free to speculate on what those might
>>> be; one that IMO carries reasonable weight is that breaking the "you
>>> need a glibc 2.18 or later package to provide symbols of 2.18 or later"
>>> invariant will confuse any users or support teams that run into a
>>> problem with a 2.18-versioned symbol and are using their 2.17 library.
>>>
>>> It would, I think, be good for someone from RedHat to describe a bit
>>> more what precisely what their constraints _are_ and what their
>>> alternate option is if the patch isn't approved, even if they are not at
>>> liberty to share the reasons for those constraints or in a position to
>>> debate them.
>>
>> Unfortunately we are not at liberty to discuss the constraints or why they
>> exist.  I will say that many are pretty obvious, some less so.  I realize
>> our inability to discuss them in any detail makes the entire discussion
>> tougher than it needs to be.  Heavy sigh....
>>
> 
> Let's assume that RedHat must use glibc 2.17 and can't move
> it to glibc 2.18/2.19.   What I don't understand is why GLIBC_2.19
> can't be used as symbol version in glibc 2.17.
 
It can. 

It's just software it can do anything.

However I've never seen it done by an distro before, and while 
technically possible it's something I'd like to avoid to reduce
risk.

We all know how to rebuild packages and it's easy and we know
there are no problems there.

Cheers,
Carlos.