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Date: Fri, 22 Apr 2005 10:33:06 -0700 (PDT)
From: Doug White <dwhite@gumbysoft.com>
To: freebsd-arch@freebsd.org
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Subject: libpthread version bump
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Hey folks,

The recent changes to implement the the %fs/%gs manipulation syscalls has
created a problem for 5.x compatibility.  While libc has been bumped for
6.x already, libpthread hasn't, so running 5.x apps on -CURRENT ends up
with the app pulling in the old libc correctly, but it pulls in the
current libpthread which depends on the new libc and the linker errors out
on the missing symbols.

I think we need to bump libpthread's version to allow for compatibility in
6. Then we can ship the old libpthread along with the old libc and the
Right Thing happens.

As it is now people have to recompile any libpthread consumer.

Another option is to create a hacked compatibility libc.so.5 that
implements the new syscalls. This is logistically difficult but doable if
just shipping the old libs isn't good enough. (I don't know the details of
the fs/gs handling, but I know it has something to do with TLS. If we want
to keep TLS working from 5.x this may be what we need to do.)

Comments?

-- 
Doug White                    |  FreeBSD: The Power to Serve
dwhite@gumbysoft.com          |  www.FreeBSD.org