I had trouble for step 3 and step 4:
3. Add a new user-defined setting CC with the value /usr/local/bin/clang-omp under the project's build settings
4. Add -fopenmp to Other C Flags under the project's build settings.

After adding "-fopenmp to Other C Flags", I got error "Unsupported option '-fopenmp'" in xcode 8.
But, in terminal, I can successfully /usr/local/bin/clang-omp++ -fopenmp.

BTW, I don't quite understand "Add a new user-defined setting CC" in step 4. In xcode, I can only find a "+" button to add a new "user-defined setting" in the project's build settings, but not the "user-defined setting CC". Not sure if they are the same thing.

It would be highly appreciated if you could kindly help me out of the mess. Thanks.