symbol versioning of private libraries builds

[tridge at samba.org]

Hi Simo,

 > Actually it hasn't.

The thing that has not changed is that the symbols in our libraries
when we bundle a library and when it is not bundled are the same. With
the change proposed by Metze we would have different symbols when the
library is bundled and when it is not bundled. I'm still looking into
whether that is a good thing or not, but it would be a significant
departure from current behaviour, so I am asking Metze to not make the
change until we can consider the implications.

I don't have time to write the test code needed to sort this out right
now. I'll do that when I have some time to spend on this.

 > We have bugs open where heimdal symbols conflicts with the system
 > library symbols for example (openchange linked by evolution that also
 > links to the system kerberos library).

That has been fixed in two ways:

 1) we use RTLD_DEEPBIND in ldb module loading, and now also in bind9
    module loading (in the patchset that is pending for the next
    release). Using external dlz modules in bind9 had the same
    MIT/Heimdal problem that openchange/evolution had.

 2) the symbol versions mean that Samba code binds to the specific
    symbol versions needed for the builtin Heimdal, which avoids the
    problem of calling into a system MIT library

Either of those changes should fix the evolution problem.

Cheers, Tridge