Re: [ft] Library versioning

[Werner LEMBERG]

> I have updated the Debian package of FreeType from 2.1.7, where it
> had been for a while, to 2.1.10. This has caused a few problems [1,
> 2] because a few symbols have gone missing - both the API and ABI
> have changed in this respect. The libtool version and soname have
> remained stable during this period, only incrementing the revision,
> when it would appear that there should have been current/age and
> major/minor changes.
>
> Is this an oversight or have I misunderstood the situation?

This is a difficult issue.  The cache interface has been declared (and
still is, IIRC) as experimental, not really part of the rest of the
FreeType code.  Increasing the current/age and major/minor numbers of
the DLL seems not appropriate for me.

I know that this may cause linking problems in case the program
doesn't properly check the availability of the exact interface, but I
don't see a better alternative, sorry.

Basically, all programs using the caching code should add a run-time
check whether it uses the correct library version: Since FT 2.0.9
there exists a function called `FT_Library_Version' which does that.


    Werner