Building wasi-sdk on Linux

[rcarmo]

If you are on OSX, I now provide a ready-so-use SDK here: https://github.com/holzschu/wasi-sdk/releases/download/wasi-sdk-aShell-19/wasi-sdk.tar.gz
It contains the binaries (clang, ar, wasm-ld...) and the sysroot, with a bunch of auxiliary libraries.
Originally posted by @holzschu in #666 (comment)

I've been trying to get the wasi-sdk to build and work on Linux, simply because that way I can do automated builds and use my existing sandboxes. However, I can't really figure out the right steps to get it to build and support setjmp.

So far, I have this Dockerfile:

FROM debian:bookworm 

RUN apt-get update \
 && apt-get install -y --no-install-recommends \
        curl \
        ca-certificates \
        build-essential \
        clang \
        python3 \
        git \
        ninja-build \
 && apt-get clean \
 && rm -rf /var/lib/apt/lists/*

RUN curl -sSLO https://github.com/Kitware/CMake/releases/download/v3.20.1/cmake-3.20.1-linux-x86_64.tar.gz \
  && tar xf cmake-3.20.1-linux-x86_64.tar.gz \
  && rm cmake-3.20.1-linux-x86_64.tar.gz \
  && mkdir -p /opt \
  && mv cmake-3.20.1-linux-x86_64 /opt/cmake
ENV PATH=/opt/cmake/bin:$PATH

RUN mkdir /build \
 && cd /build \
 && git clone --recurse-submodules https://github.com/holzschu/wasi-sdk.git \
 && cd wasi-sdk \
 && git fetch --all --tags \
 && git checkout tags/wasi-sdk-aShell-19

ENV PREFIX=/opt/
RUN cd /build/wasi-sdk \
 && sed '296,316{s/^/#/}' src/llvm-project/clang/CMakeLists.txt > /tmp/clean \
 && mv /tmp/clean src/llvm-project/clang/CMakeLists.txt \
 && make

This builds and seems to work, but lacks a lot of the extra libraries and headers in the OSX tarball above.

What else do I need to do? I'd like to have a reproducible SDK build...

[holzschu]

I cannot test, but I think you also need to download the SDK from https://github.com/holzschu/wasi-sdk/releases/download/wasi-sdk-aShell-19/wasi-sdk.tar.gz , extract it, and copy .../share/wasi-sysroot/ over the wasi-sysroot that you have built with the previous steps (or, at least, copy the extra libraries and headers).

[rcarmo]

Thanks. I'd really like to have a working recipe for building everything from scratch, since (for instance) the Dockerfile above generates things with clang-14, and I see clang-19 in your tarball. Since when I travel with my iPad I take one of these ARM devices as a "sidecar" for development and not a Mac, I'd like to have a toolchain I can run there...

Do you have any notes on the build steps for your tarball?

[holzschu]

There must be something wrong with the release. I'll commit and push again from wasi-sdk.