anchor.diff:  
   # Fail if any non-portable instructions were used
   RUN /bin/bash -e -c 'if objdump -d /vg/bin/vg | grep vperm2i128 ; then exit 1 ; else exit 0 ; fi'
  +# Set the default number of threads to the number we are supposed to use.
  +ENV OMP_NUM_THREADS ${THREADS}
   # Run tests in the middle so the final container that gets tagged is the run container.
   RUN make test
   
  
positive.code: WORKDIR /vg
  
  FROM base AS build
  
  RUN echo build > /stage.txt
  
  
negative.code: # This has no AVX1, AVX2, or PCLMUL, but it does have SSE4.2.
  # UCSC has a Nehalem machine that we want to support.
  RUN sed -i s/march=native/march=nehalem/ deps/sdsl-lite/CMakeLists.txt
  RUN make get-deps && . ./source_me.sh && env && make include/vg_git_version.hpp && CXXFLAGS=" -march=nehalem " make -j ${THREADS} && make static && strip bin/vg
  
  ENV PATH /vg/bin:$PATH
  
  ############################################################################################
  FROM build AS test
  ARG THREADS=8
  
  RUN echo test > /stage.txt
  
  