anchor.diff:  FROM project5/base
   MAINTAINER benjamin.gemmill@gmail.com
   
  +ARG LLVM_VERSION=7
  +
   # clang repository from https://apt.llvm.org
   RUN apt-get update && apt-get install -y \
         software-properties-common curl \
         && curl https://apt.llvm.org/llvm-snapshot.gpg.key | apt-key add - \
  -      && apt-add-repository "deb http://apt.llvm.org/`lsb_release -cs`/ llvm-toolchain-`lsb_release -cs`-6.0 main"
  +      && apt-add-repository "deb http://apt.llvm.org/`lsb_release -cs`/ llvm-toolchain-`lsb_release -cs`-${LLVM_VERSION} main"
   
   RUN apt-get update && apt-get install -y \
         sudo \
  
positive.code:       && git config --global core.editor "vim"
  
  # Clang
  RUN update-alternatives --install /usr/bin/clang clang /usr/bin/clang-6.0 1000 \
    && update-alternatives --install /usr/bin/clang++ clang++ /usr/bin/clang++-6.0 1000 \
    && update-alternatives --install /usr/bin/lldb lldb /usr/bin/lldb-6.0 1000
  ENV CC=/usr/bin/clang
  ENV CXX=/usr/bin/clang++
  
  
negative.code:       default-jdk \
        python python-dev python-pip \
        python3 python3-dev python3-pip \
        clang-${LLVM_VERSION} lldb-${LLVM_VERSION} lld-${LLVM_VERSION} \
        cmake make ccache \
        libssl-dev libz-dev
  
  