I found that the easiest way to get a functioning toolchain to build vlc-winrt for x86 and x64 was to adapt one of the docker image files, such as this one:
https://code.videolan.org/videolan/dock ... nrt-x86_64
After turning this into a bash script it built the toolchain on a fresh install of Ubuntu Zesty and I was subsequently able to build vlc-winrt from a slightly older version (latest code doesn't build by the way, as can be seen by the absence of nightlies in the last few weeks) by following the instructions on the wiki and executing "./compile.sh x86_64 win10".
However, there is no such docker file for the toolchain for th ARM version and I wondered if anyone knows the correct way to build a toolchain that will allow building ARM vlc-winrt via the command "./compile.sh armv7 win10"?