handlers when a thread is cancelled which has the side effect that
programs linked with librt fail on Fedora Core 2 due to librt having
been built against the NPTL header instead of the old pthread headers.
This change extends valgrind's libpthread.so to handle both the old
and new style cleanup handlers in a similar way to NPTL and seems to
be sufficient to get programs linked with librt working again.
git-svn-id: svn://svn.valgrind.org/valgrind/trunk@2405
