Dockerfile

ARG BASE=ubuntu:24.04
FROM $BASE
ENV DEBIAN_FRONTEND=noninteractive TZ=UTC
ARG EMSCRIPTEN_VERSION=3.1.47

# Install prerequisites for building LLVM, R, and webR wasm system libraries
RUN apt-get update && apt-get -y install --no-install-recommends \
    build-essential \
    ca-certificates \
    clang \
    cmake \
    curl \
    gfortran \
    gh \
    git \
    gnupg \
    gperf \
    jq \
    libbz2-dev \
    libcurl4-openssl-dev \
    libglib2.0-dev-bin \
    liblzma-dev \
    libpcre2-dev \
    libssl-dev \
    libxml2-dev \
    libz-dev \
    lld \
    ninja-build \
    pkg-config \
    python3 \
    python3-setuptools \
    quilt \
    sqlite3 \
    sudo \
    tzdata \
    unzip \
    wget

# Install emsdk
RUN git clone --depth=1 https://github.com/emscripten-core/emsdk.git /opt/emsdk
WORKDIR /opt/emsdk
RUN ./emsdk install "${EMSCRIPTEN_VERSION}" && \
    ./emsdk activate "${EMSCRIPTEN_VERSION}"

# Build LLVM flang
COPY Makefile /root/flang-wasm/Makefile
RUN . /opt/emsdk/emsdk_env.sh && \
    cd /root/flang-wasm && \
    make PREFIX="/opt/flang" FLANG_WASM_CMAKE_VARS="-DCMAKE_C_COMPILER=clang \
        -DCMAKE_CXX_COMPILER=clang++ -DLLVM_USE_LINKER=lld" && \
    make PREFIX="/opt/flang" install

# Clean up
RUN . /opt/emsdk/emsdk_env.sh && emcc --clear-cache
RUN rm -rf /root/flang-wasm /opt/emsdk/downloads/*
RUN apt-get clean && rm -rf /var/lib/apt/lists/*

# Squash docker image layers
FROM $BASE
ENV DEBIAN_FRONTEND=noninteractive TZ=UTC
COPY --from=0 / /
SHELL ["/bin/bash", "-c"]