[Date Prev][Date Next] [Thread Prev][Thread Next] [Date Index] [Thread Index]

Bug#729203: Rebuild of possible FFmpeg reverse build-dependenciesa

Hi Niv,

On 04.05.2014 13:03, Niv Sardi wrote:
I haven't gotten the time to look more into this, and am now in a 25hrs
bus with limited internet access.

I see.

My rationale is this:
- I don't want to ofend the libav maintainers nor want them to go on a
+300 api bump.

I don't want to offend them as well, but I don't see, why they should have to make any API bump.

- I don't want anything breaking in debian because users pick our lib on
a package that was meant to link to libav and somehow breaks.

To prevent this, FFmpeg is compiled with the --enable-raise-major option, so that the FFmpeg SONAME is increased by 100. So no package that does not depend on the FFmpeg libraries will use them. (Except maybe, if you still use that library in 100 years, which I don't think anyone will do.)

If we keep the names as they are, on next dist-upgrade everybody
depending on libavblah will pull it. If we want that, we should go tech
ctte and take over Libav, but that wasn't the consensus.

No, a dist-upgrade will not upgrade libavcodec54 to libavcodec155, it will only install libavcodec155, if any package depends on it and only remove libavcodec54, if no package depends on it anymore. And there is no problem at all, if libavcodec54 and libavcodec155 are installed in parallel, because the SONAME is different.

I wanted to see if we had an easy way to alter the soname so this lib is
seen as an alternative to the other one and if we can keep packaging in
line with policy. In the defect of such possibility, I feel we should
rename to libavblah-ffmpegSoname.

I think the easy way you are looking for is --enable-raise-major and this is already used. And changing the name of the library will not change much, as these libraries usually only get installed as dependencies, so the user will not see the name. As this package would still include libavcodec.so.155, it will have the same (theoretical) problems in 100 years, when the Libav libavcodec SONAME reaches 155.

So I have the feeling that here is kind of a misunderstanding about the effect of changing the package name. To be perfectly clear: libavcodec155 from FFmepg and libavcodec54 from Libav are co-installable and work fine, if both are installed. You can try this, by installing the ffmpeg package and the needed libraries.
This will not break any existing installed program.

Best regards,

Reply to: