Using WebAssembly in LLVM on Windows
Forewarning: this can be a bit painful and may not work as expected. I've already had issues with even including stdlib through clang.
Make sure you have git installed and properly configured before continuing. This is trivial on Windows these days (https://git-scm.com/download/win) but is required to pull down Binaryen and Wabt.
Make sure to add the binary to your PATH variable in Windows.