Dockerfile to build a relatively portable armv6 linux binary.

Dockerfile

# -*- mode: dockerfile -*-
# Dockerfile to build openblas for armv6
FROM dockcross/linux-armv6

ENV ARCH armv6l
ENV BUILD_OPTS "USE_BLAS=openblas USE_SSE=0 USE_OPENCV=0"
ENV CC /usr/bin/arm-linux-gnueabihf-gcc
ENV CXX /usr/bin/arm-linux-gnueabihf-g++
ENV FC /usr/bin/arm-linux-gnueabihf-gfortran
ENV HOSTCC gcc

WORKDIR /work

# Build OpenBLAS
ADD https://api.github.com/repos/xianyi/OpenBLAS/git/refs/heads/master openblas_version.json
RUN git clone https://github.com/xianyi/OpenBLAS.git && \
    cd OpenBLAS && \
    #git reset --hard 46c9357c72801f4e186b56abcf7b75d3fad767ab && \
    make -j$(nproc) TARGET=ARMV6 && \
    make install && \
    ln -s /opt/OpenBLAS/lib/libopenblas.so /usr/lib/gcc/arm-linux-gnueabihf/libopenblas.so && \
    ln -s /opt/OpenBLAS/lib/libopenblas.a /usr/lib/gcc/arm-linux-gnueabihf/libopenblas.a && \
    ln -s /opt/OpenBLAS/lib/libopenblas.a /usr/lib/gcc/arm-linux-gnueabihf/liblapack.a && \
    ln -s /opt/OpenBLAS/lib/libopenblas.a /usr/lib/liblapack.a

ENV LD_LIBRARY_PATH /opt/OpenBLAS/lib
ENV CPLUS_INCLUDE_PATH /opt/OpenBLAS/include