Build using Emscripten

In root:

source /opt/emsdk/emsdk_env.sh --build=Release
mkdir -p build
cd build
cmake -GNinja -DEMSCRIPTEN=1 ..
ninja

Note:

To enable tail-call WebAssembly extension:

cmake -GNinja -DEMSCRIPTEN=1 -DWASM_TCO=1 ..

You can convert the generated wasm to wat to see the effect:

wasm2wat --enable-tail-call wasm3.wasm > wasm3.wat

Running tail-call version will require Chrome with experimental flags:

emrun --no_browser --no_emrun_detect --port 8080 .
chrome --js-flags="--experimental-wasm-return-call --wasm-opt --wasm-no-bounds-checks --wasm-no-stack-checks" http://localhost:8080/wasm3.html

Or use Node.js:

node --experimental-wasm-return-call --wasm-opt ./wasm3.js