- Since CUDA 9.1 doesn't support LLVM 9.0.0, you need to install Command Line Tool 8.3.2 and switch:
$ sudo xcode-select --switch /Library/Developer/CommandLineTools/
$ clang --version
Apple LLVM version 8.1.0 (clang-802.0.42)
Target: x86_64-apple-darwin17.3.0
Thread model: posix
InstalledDir: /Library/Developer/CommandLineTools/usr/bin
- CTL 8.3.2 is supposed for macOS Sierra 10.12, so you also need to create a symbol link for SDK.