anchor.diff:  ARG RISCV_TOOLCHAIN_TAR_VERSION
   ARG RUST_VERSION
   ARG BAZELISK_VERSION
  +ARG GCC_VERSION
   
   LABEL version="1.0"
   LABEL description="OpenTitan development container."
  
positive.code: # - locales and locales-all are required to set the locale.
  # - minicom and screen are useful to see UART communication.
  # - dc and time are requirements of Synopsys VCS.
  COPY apt-requirements.txt /tmp/apt-requirements.txt
  RUN echo "verilator-${VERILATOR_VERSION}" >>/tmp/apt-requirements.txt \
      && echo "openocd-${OPENOCD_VERSION}"     >>/tmp/apt-requirements.txt \
      && sed -i -e '/^$/d' -e '/^#/d' -e 's/#.*//' /tmp/apt-requirements.txt \
      && apt-get update \
      && xargs apt-get install -y </tmp/apt-requirements.txt \
  
negative.code:         screen \
          dc \
          time \
          software-properties-common \
      && apt-get clean; \
      rm -rf /var/lib/apt/lists/* /tmp/* /var/tmp/* /usr/share/doc/*
  
  # Install the CI version of gcc and g++
  RUN add-apt-repository ppa:ubuntu-toolchain-r/test \
      && apt-get update \
      && apt-get install -y gcc-9 g++-9 \
      && update-alternatives --install /usr/bin/gcc gcc /usr/bin/gcc-9 90 \
      && update-alternatives --install /usr/bin/g++ g++ /usr/bin/g++-9 90
  
  # RISC-V device toolchain
  COPY util/get-toolchain.py /tmp/get-toolchain.py
  