# build under docker using archlinux container
$ docker run -it archlinux
# install dependant tools
$ pacman -Sy --noconfirm git base-devel cmake mingw-w64-gcc python
# get PKGBUILD from this/current REPO
$ git clone https://github.com/bpangWR/archlinux_llvm_project_win64.git
$ cd archlinux_llvm_project_win64
# build with user 'nobody', 'root' is not allowded using makepkg
$ chown nobody .
$ sudo -u nobody makepkg --skipinteg