wget https://github.com/llvm/llvm-project/releases/download/llvmorg-12.0.0/clang+llvm-12.0.0-x86_64-linux-gnu-ubuntu-20.04.tar.xz
tar -xf clang+llvm-12.0.0-x86_64-linux-gnu-ubuntu-20.04.tar.xz
cd clang+llvm-12.0.0-x86_64-linux-gnu-ubuntu-20.04
cd OBJ_ROOT
cmake -G "Unix Makefiles" -DCMAKE_INSTALL_PREFIX="$1"/usr/bin
make -j`nproc`
make install DESTDIR="$1"