message: make install requires sudo
diff: language: cpp
  dist: xenial
  -sudo: false
  +sudo: required
  git:
  depth: 3
  env:
  @@ -26,7 +26,8 @@ install:
  - tar xf CGAL-4.12.1.tar.xz
  - cd CGAL-4.12.1
  - cmake -DCMAKE_BUILD_TYPE=Release -DCGAL_HEADER_ONLY=ON .
  - - make all install
  + - make all
  + - sudo make install
  - cd ..
  script:
  - mkdir -p build
  