preparing new RtMidi release, question about SO version

[Felipe Sateler]

Hi Stephen

On 10 February 2016 at 14:21, Stephen Sinclair <radarsat1 at gmail.com> wrote:
>
> Hello,
>
> I am helping to update RtMidi, a C++ class for cross-platform MIDI
> support.  There is a Debian librtmidi package.  Although this is just
> a bug-fix release, and is planned to go from 2.1.0 to 2.1.1, we have
> added some automake/libtool infrastructure, and a last debate is
> whether to properly start supporting SO version according to libtool's
> rules.

Cool. I would be careful, though, because for C++ seemingly innocent
changes can break the ABI. STK[1] was recently updated to use
libtool's -release style versioning to avoid problems, as some changes
broke ABI and were not noticed by upstream as such. This is
particularly important for libraries that are used as static libraries
(as this kind of breakage might go unnoticed for a  while).


[1] https://github.com/thestk/stk/pull/27
>
> Previous versions have made the error of treating SO version like the
> version number, and producing binaries e.g. librtmidi.so.2.1.0.
>
> I was recommending changing this to properly reflect ABI
> compatibility.  What would Debian maintainers prefer here?

If (and only if) proper ABI versioning can be done, then I'd prefer
that, of course. But using a -release style versioning would also be
ok, and force rebuild of all reverse depedends on each upstream
version. This should be ok, as there aren't many (6 by my count). This
has the advantagae for upstream that they do not have to care about
abi.

>
> I proposed making the new SO version 3.0.0, to really emphasize that
> the ABI version is new, however since it's a bugfix release I don't
> know if that's the recommended strategy.
>
> https://github.com/thestk/rtmidi/pull/59
>
> In any case I notice that the interface has changed a bit, e.g. some
> functions have lost parameters, others have new parameters, since the
> last release.

I see the pull request has already been merged. I hope this message
doesn't come too late.

-- 

Saludos,
Felipe Sateler