This repository builds a compilation toolchain in Fix that compiles WASM modules to ELF.
To build this project, you need to first build
fix-project/wasm-toolchain,
and wasm-toolchain needs to be placed at $ENV{HOME}/wasm-toolchain.
Run git submodule update --init --recursive.
./build-all.sh
After building, there should be a .fix/ in the source directory
of the project. Copy this directory to the source directory of Fix.
Since a full build takes a really long time, it's really helpful to build
bootstrap incrementally. Unfortunately, traditional build systems don't really
handle the kind of incrementality we need. In particular, timestamp based
systems like Make or Ninja will always think the fix side of bootstrap needs to
be recompiled, since even if wasm-to-c-sys outputs the exact same files,
it'll update the timestamps on those files anyway.
Obviously, running bootstrap within Fix would solve this problem instantly; Fix will used the cached compilation if it sees matching hashes. Outside of Fix, we can achieve similar results using Zach Yedidia's new build system, knit, which supports hash-based dynamic task elision (i.e., the equivalent of memoizing tasks in Fixcache). This isn't quite as efficient as building within Fix would be, since Knit can only elide a task if the output is already on disk in the right location, but is still a significant improvement in the common case.
To build bootstrap using Knit, add knit to your path and run:
knit -j $(nproc)
This will automatically rebuild the drivers using CMake, then run the bootstraping process incrementally.
To rebuild a specific file, run:
knit [file] -j $(nproc)
If you're on stagecast.org, there's a pre-built knit binary at
/opt/knit/bin/knit.