It's not that we wanted to give you a world of pain. It was that we wanted to avoid lots of
pain that is involved in this specific case when two DIFFERENT ABI version of libexpat are on
a system. Library A depends on expat and library B depends on library A and expat - Library A
gets rebuilt and will use libexpat.so.1 version, while library B still uses libexpat.so.0.
User launches an application linking to Library B, both expat versions are mapped in and
providing symbols, things get mixed up between them, enter a world of chaos and random hard to
explain crashes caused by the specific case this library works and is used, which made
preserve_old_lib method usage not a good option as that leads to exactly that chaos crashy
We do not have a mechanism in place to avoid that. Manually it was possible to workaround it
by making a libexpat.so.0 pointing at libexpat.so.1, because then the same library is used by
both library A and B, but in this instance this workaround it worked just for most cases due
to the ABI breakage being small.
And yes, I am one (out of about three or four) persons responsible for the decision on which
route we went with the expat upgrade and I stay by it.