Re: libtool versioning and ABI

[Ralf Wildenhues]

Hello Michel,

* Michel Briand wrote on Thu, Aug 06, 2009 at 12:46:00AM CEST:
> Personally I've always seen interface as a contract.
> A contract between a library writer and library user.

Yes.

> Why does libtool want to interfere with this ... has always made me
> scratching my head....

libtool allows you to exploit the versioning capabilities of the runtime
linkers on different systems.  Not all the world is a GNU/Linux box, and
some non-glibc runtime linkers have different versioning semantics.

> Since it's a contract, ABI changes fall into the contract agreement. So
> why bother with complex versionning and error-prone version
> manipulations with substraction

*You* the developer that uses libtool shouldn't ever need to use
subtraction.  libtool does that for you.

> The difficult, and somehow messy, scheme of libtool versioning is
> boring and uneasy : developers do not understand this different way
> that overlap with the classical, natural and contractual scheme (X.Y.Z
> that one can still use with the -release flag) ; and this create
> additional work to handle package version (official, classical) in
> parallel with libtool -version-info scheme.
> 
> Or I'm completely wrong.... but the documentation lacks some clues
> about what is this all about ;)))

Yes, you are wrong.  You are simply doing non-GNU/Linux users a
disservice, by effectively disabling library versioning capabilities for
them.  I'm not sure how to best explain that to you.

Cheers,
Ralf