What happens

  • CMake fatal error with message [hunter ** FATAL ERROR **] 'xcrun -f clang++' failed

What to do

  • xcrun [1] is a part of Xcode environment. Probably xcode is broken or not installed at all. May be command line tools need to be installed also. After that, simply check that xcrun -f clang++ returns the full path to clang compiler. See also xcode-select [2].