[FFmpeg-devel] [PATCH] restoring binary compatibility with ffmpeg 0.5

[Reinhard Tartler]

On So, Jun 06, 2010 at 22:29:25 (CEST), Reimar D?ffinger wrote:

> However here we have the problem that this would break e.g. on Solaris,
> since a symbol is not allowed to have multiple versions there.
> I think the real mistake was made during the move: the version should
> never have been changed, despite the move to a different library...
> Am I right that changing the linker script to
> LIBAVFORMAT_52 {
>         global: av_init_packet;
> };
> LIBAVCODEC_$MAJOR {
>         global: *;
> };
> would avoid the compatibility issue with 0.5 (though breaking it
> for several versions in-between)?

I've tried this as well, but unfortunately, this doesn't work out:

>> objdump -T /tmp/ffmpeg/lib/libavcodec.so.52 | grep av_init_packet
000c0ce0 g    DF .text	00000058  LIBAVFORMAT_52 av_init_packet

>> ffplay /tmp/Elephants_Dream-720p-Stereo.webm
FFplay version SVN-r0.5.1-4:0.5.1-1ubuntu1, Copyright (c) 2003-2009 Fabrice Bellard, et al.
  configuration: --extra-version=4:0.5.1-1ubuntu1 --prefix=/usr --enable-avfilter --enable-avfilter-lavf --enable-vdpau --enable-bzlib --enable-libgsm --enable-libschroedinger --enable-libspeex --enable-libtheora --enable-libvorbis --enable-pthreads --enable-zlib --disable-stripping --disable-vhook --enable-runtime-cpudetect --enable-gpl --enable-postproc --enable-swscale --enable-x11grab --enable-libdc1394 --enable-shared --disable-static
  libavutil     49.15. 0 / 49.15. 0
  libavcodec    52.20. 1 / 52.72. 2
  libavformat   52.31. 0 / 52.64. 2
  libavdevice   52. 1. 0 / 52. 2. 0
  libavfilter    0. 4. 0 /  0. 4. 0
  libswscale     0. 7. 1 /  0.11. 0
  libpostproc   51. 2. 0 / 51. 2. 0
  built on Mar  4 2010 12:35:30, gcc: 4.4.3
ffplay: relocation error: ffplay: symbol av_init_packet, version LIBAVFORMAT_52 not defined in file libavformat.so.52 with link time reference

It seems that this symbol really needs to be in libavformat.


-- 
Gruesse/greetings,
Reinhard Tartler, KeyID 945348A4