[RFC] change packaging around shared libraries, ldconfig

[Jakub Jelinek]

On Wed, Jun 27, 2007 at 10:42:31AM -0400, Bill Nottingham wrote:
> Jeff Spaleta (jspaleta at gmail.com) said: 
> >> If the cache is stale, it will look in the directories for something that
> >> doesn't exist in the cache. I'm trying to think of a way the cache could
> >> point to the wrong *version* of the library, but nothing is coming to
> >> mind.
> >
> > Pathological case?
> > Forcing the install of a duplicate library package when there is a
> > soname version bump and there isn't a compat package and you want to
> > keep the old library version on your local system?
> 
> Then the soname doesn't match, so it will DTRT anyway. If the soname
> is the same, you'll only have the new library on the system, so the
> cache can't be 'stale' there either in a way that gives you the wrong
> library.

Well, if you are moving the same SONAME to a different path (found earlier
in ldconfig's search path) and adding new symbols at the same time, you can
have issues.
Say, package foobar used to have libfoobar.so.1 in /usr/lib64, a new
version moves it to /lib64 because barbaz program needs it before /usr is
mounted.  If it adds a new symbol foo to that library at the same time
and /bin/bar program which is run during %post needs it, you loose
without ldconfig run.

	Jakub