Re: libpthread.so.2 compatibility

On Sun, 4 Jun 2006, John Hay wrote:

>>>>> FWIW, I just upgraded a system from an early January -CURRENT, and I'm
>>>>> getting the same thing.  I've already rebuilt most things, which
>>>>> probably means there'll be a "fix" for this that requires rebuilding
>>>>> them again   :p
>>>>
>>>> There have been no ABI changes in libpthread, so it must be coming
>>>> from somewhere else.  I know that libc had some ABI changes but
>>>> it's version was bumped to account for that.
>>>>
>>>> libpthread did move from /usr/lib to /lib, but I don't know how
>>>> that would bite you unless you deleted it from /usr/lib in the
>>>> upgrade process.
>>>
>>> Ok, maybe it isn't some ABI change inside libpthread. Can it maybe be
>>> that we have two "versions" of libpthread.so.2 now, one that was
>>> compiled and like to be linked to libc.so.6 and one that like to be
>>> linked to libc.so.7? So if you now try to run an older threaded app
>>> (one that was compiled with libc.so.6 and libpthread.so.2, like what
>>> would happen in FreeBSD-6) on -current, it would try to use the new
>>> libpthread.so.2 that was build against libc.so.7, but try to link it
>>> with libc.so.6 and then crash and burn? Maybe when libc gets bumped
>>> all other libs have to be bumped too?
>>
>> All others have to be bumped anyway (in -current) but I don't know
>> if that is what is causing the problem.  ldd or readelf -d are your
>> friends...  If there are multiple dependencies on libpthread, then
>> that is probably causing the problem.
>
> I have done it, but do not see anything strange. ldd looks like this,
> with and without  the libmap.conf tweak:

[ ... ]

> Actually one does not even need a big complex app to see the problem.
> Just copy /sbin/ggatec from 6.1 or 6.1-stable to a current box and you
> will see it happen:
>
> #######
> angel:~ > uname -a
> FreeBSD angel.cids.org.za 7.0-CURRENT FreeBSD 7.0-CURRENT #2: Sun May 28 11:06:16 SAST 2006     jhay_at_angel.cids.org.za:/usr/src/sys/i386/compile/ANGEL  i386
> angel:~ > ssh zibbi "uname -a"
> FreeBSD zibbi.meraka.csir.co.za 6.1-STABLE FreeBSD 6.1-STABLE #4: Thu May 25 06:11:44 SAST 2006     jhay_at_zibbi.meraka.csir.co.za:/usr/src/sys/i386/compile/ZIBBI  i386
> angel:~ > scp -p zibbi:/sbin/ggatec /tmp/
> ggatec                                        100%   16KB   8.1KB/s   00:02
> angel:~ > /tmp/ggatec
> Segmentation fault (core dumped)
> #######

It is probably the networking ABI changes in libc.  There was a short period
of time when there were ABI changes in libc.so.6 in -current -- before libc
was bumped to libc.so.7.  What happens when you try moving a -stable libc.so.6
to the -current machine?

-- 
DE