anchor.diff:  ARG CFLAGS="-D_GLIBCXX_USE_CXX11_ABI=0 -fPIC -g -fno-omit-frame-pointer -O3 -pthread"
   ARG CXXFLAGS="-D_GLIBCXX_USE_CXX11_ABI=0 -fPIC -g -fno-omit-frame-pointer -O3 -pthread"
   
  -ARG FOLLY_SHA=a1b77701d8619afc907ba0408d03aadecf852e02
  +ARG FOLLY_SHA=e756d07cd35714d7528444321ea5145b41f5ae0f
   ARG WANGLE_SHA=d67b7632be2923de3695201c7ac361f50646bbbf
   ARG PROXYGEN_SHA=ab90f2a9f0709180a2df726278d8692a5da11c79
  -ARG BUCK_SHA=ac9d60eb155f9fdfa946cb23d17adafa8ab8609c1
  +ARG BUCK_SHA=b5c1b24d8f25be5c96e8bce0a70c4665870a5749
   ARG GTEST_SHA=13206d6f53aaff844f2d3595a01ac83a29e383db
   ARG DOUBLE_SHA=7499d0b6926e1a5a3d9deeb4c29b4f8bfc742c42
   ARG WATCHMAN_VER=v4.5.0
  
positive.code: 
  # Add utils to enable changing apt lists
  # And then add them on.
  RUN apt-get update && \
      apt-get -qq -y install \
         apt-utils \
         python-software-properties \
         software-properties-common \
         wget && \
      wget -O - http://llvm.org/apt/llvm-snapshot.gpg.key | apt-key add - && \
      add-apt-repository 'deb http://llvm.org/apt/wily/ llvm-toolchain-wily-3.7 main' && \
      apt-add-repository ppa:ubuntu-toolchain-r/test && \
  
negative.code:     ant && \
      ln -s /usr/src/buck/bin/buck /usr/local/bin/buck && \
      ln -s /usr/src/buck/bin/buckd /usr/local/bin/buckd && \
      ( /usr/local/bin/buck --help || true ) &&  \
      rm -rf /usr/src/buck/.git && \
      rm -rf /usr/src/buck/test
  
  