wget https://github.com/llvm/llvm-project/releases/download/llvmorg-12.0.1/llvm-12.0.1.src.tar.xz
tar -xf llvm-12.0.1.src.tar.xz
cd llvm-12.0.1.src

mkdir build

cmake -B build -G 'Unix Makefiles'
cd build
make
make DESTDIR="$1" install