Craft (as of today) doesn't allow the use of the now installable LLVM compilers in windows. It only presents the following options: Select compiler [0] Mingw-w64, [1] Microsoft Visual Studio 2015, [2] Microsoft Visual Studio 2017 (Default is Microsoft Visual Studio 2017):
Hi, that is a valid wish but will not happen if nobody contributes it. If you like to help out, join us on: https://invent.kde.org/packaging/craft