Bug#892325: Outdated Linphone packets

[Bernhard Schmidt]

Hi Julien,

> I'm not fully aware about the packaging process on Debian but Linphone
> Desktop 4.2 will be based on 4.4 of SDK for sure.
> 
> Even it is currently on development, the 4.4 is near to be released and
> is enough stable to begin to work with. In addition, I think that you
> will have to use all 4.4 libraries because there is no point to mix
> versions. I can confirm you that the Doxygen issue is fixed on this
> version.

So if I get you correctly, the only supported way to build and run
linphone-desktop 4.2.x will with all of
bctoolbox/belle-sip/ortp/mediastreamer2/bzrtp/belr/belcard/liblinphone
4.4.x?

When updating your libraries, will newer versions (i.e. 4.4) either be
API/ABI compatible with the previous versions (i.e. 4.3) or have a
SONAME bump? Sid/Testing is basically a rolling distribution, we need to
be able to start upgrading for example belle-sip with the new upstream
version without fatally breaking the not-yet-updated part.

In other words, I have understood that building (for example) linphone
4.4 with belle-sip/mediastreamer 4.3 is not supported. Is building
liblinphone 4.3 with belle-sip/mediastreamer 4.4 supported?

Debian tries to have as relaxed dependencies as possible. If for example
liblinphone would be built with belle-sip 4.4 present, but only use
library symbols that are already present in belle-sip 4.3.1, the build
system would express a dependency of "libbellesip0 (>= 4.3.1)". In
general Debian would allow a partial upgrade, a runtime error would be a
bug. So if that's the case we need to make sure all libraries migrate at
once and have very tight relationships (both at build-time and for the
binary packages).

https://wiki.debian.org/UpstreamGuide has a lot of information.

> By the way, an Appimage on the last version of the application is based
> on 4.4.0-beta-13 and can be found here :
> https://www.linphone.org/snapshots/AppImages/Linphone-4.2.0-alpha.63+59c4cc1.AppImage

If your whole development model is catered around AppImage (or snaps)
and basically only supports atomically replacing the whole stack and
building it from a single repository I would rather not have linphone in
Debian at all. After all we have to support it for several years after
release.

Bernhard