Bug#654303: libav: undocumented API change: libavutil/avutil.h doesn't include mathematics.h any more

[Jonathan Nieder]

Package: libavcodec-dev
Version: 4:0.8~beta1-2
Severity: minor
Justification: documentation
Tags: upstream
Files: /usr/share/doc/libavcodec-dev/APIchanges.gz

Reinhard Tartler wrote:

> Package: chromium-browser

(Please use "Source: chromium-browser" in the future.)

[...]
> A local rebuild of your package reveals a build failure against libav
> 0.8, which can be found in debian/experimental.
[...]
>>   CXX(target) out/Release/obj.target/media/media/filters/audio_file_reader.o
>> media/ffmpeg/ffmpeg_common.cc: In function 'base::TimeDelta media::ConvertFromTimeBase(const AVRational&, int64)':
>> media/ffmpeg/ffmpeg_common.cc:15:70: error: 'av_rescale_q' was not declared in this scope

Chromium's ffmpeg support includes headers

	#include <libavcodec/avcodec.h>
	#include <libavformat/avformat.h>
	#include <libavformat/avio.h>
	#include <libavutil/avutil.h>
	#include <libavutil/log.h>

Previously avutil.h included mathematics.h, so this worked fine.
Since v0.8b1~2231 (Do not include mathematics.h in avutil.h,
2011-06-04), avutil.h no longer does so, to avoid namespace pollution.
There were some other similar fixes in the same vein in the same patch
series.  Sensible enough.

But that is definitely an API change that application authors could
save time by being able to read about.  Could you add a note to
doc/APIchanges?

Thanks much,
Jonathan