CMake Error at .*/Modules/CheckIncludeFiles\.cmake:[0-9]+ \(message\):
  Unknown language:

    FOOBAR

  Supported languages: C, CXX\.

Call Stack \(most recent call first\):
  CheckIncludeFilesUnknownLanguage\.cmake:[0-9]+ \(check_include_files\)
  CMakeLists\.txt:[0-9]+ \(include\)