NPTL for hppa-linux is not backwards compatible with Linuxthreads.

["Carlos O'Donell" <carlos@systemhalted.org>]

NPTL for hppa-linux is not backwards compatible with Linuxthreads, we
have broken the pthread ABI.

I made the choice. I told people we were breaking the ABI. We even
looked at weird alternatives. In the end I felt we could not sanely
support NPTL with "load and clear word" primitives. When I say
"support" I also include future work, maintenance, and upstream
integration. The NPTL implementation uses a kernel helper, and brings
hppa-linux in line with all other architectures.

The hard part is transitioning from Linuxthreads to NPTL.

It has been recommended that we bump to libc6.1 for NPTL. Is that a
good idea? Are there any comments about how to make such a transition
smooth for debian, gentoo, and ubuntu?

I'm looking for guidance on this matter. We need help :-)

Cheers,
Carlos.