cppfront to WASM

This repository contains a tiny hello world example for compiling cppfront (aka C++ Syntax 2) to WASM, using clang or optionally zig.

Requires that cppfront is in the path. The Makefile also needs to be modified at the top to point the include directory for cppfront to the right place.

Setup (no zig)

Install LLVM via Homebrew and link

brew install llvm \
    && echo 'export PATH="$(brew --prefix)/opt/llvm/bin:$PATH"' >> ~/.zshrc \
    && source ~/.zshrc

Download releases from WebAssembly/wasi-sdk:

wget "https://github.com/WebAssembly/wasi-sdk/releases/download/wasi-sdk-19/wasi-sysroot-19.0.tar.gz" \
    && wget "https://github.com/WebAssembly/wasi-sdk/releases/download/wasi-sdk-19/libclang_rt.builtins-wasm32-wasi-19.0.tar.gz" \
    && tar xf wasi-sysroot-19.0.tar.gz \
    && tar xf libclang_rt.builtins-wasm32-wasi-19.0.tar.gz

Move the lib/wasi directory extracted to clang lib (note: versions may differ):

mv lib/wasi $(brew --prefix)/Cellar/llvm/15.0.7_1/lib/clang/15.0.7/lib/ \
    && rm -d lib

Then

make

Run it with bytecodealliance/wasmtime:

wasmtime cart.wasm
# Hello world from cppfront!

Cool and nice and fast with zig

Use Zig target (none of the above required, only needs zig in PATH):

make zig

Recommended tools

• WebAssembly/wabt