In order to use the latest stable version of tvheadend with kodi-18 which requires ffmpeg-4.1, I had to patch the sources to conform to the new ffmpeg API. Reproducible: Always
Created attachment 557906 [details] patch muxer_libav.c to adapt to the new ffmpeg API.
Created attachment 557908 [details, diff] patch transcode.c to adapt to the new ffmpeg 4.1 API.
Created attachment 557910 [details] tvheadend-4.3.ebuild
I overlooked the patch-flag while creating the first attachment, but I don't know how to enable it afterwards...
4.3 is not the latest stable release, it is a prerelease from May 2017. 4.2.2 through to 4.2.8 have been release since and at least 4.2.7 builds against ffmpeg 4.1 just fine.