artifacts when encoding 444 10bit input

[Selur]

Got some artifacts when feeding x265 with 10bit 4:4:4 content. see image: https://postimg.cc/image/6lyuywbhl/

Problem does happen with x264 and x265. Problem does happen when using vpxenc or playing the source or the output with ffplay. Posted command line calls I used over at Doom9 (https://forum.doom9.org/showthread.php?t=174314), would be nice if someone could look into it.

Used version 2.2+36-9b975fec584a compiled with https://github.com/jb-alvarado/media-autobuild_suite on Win10 64bit using a i7-4770k.