unexpected malloc and free errors

[parallastra]

after building and launching the example server as follows:

git clone --recurse-submodules https://github.com/parallastra/zstd-wasm.git
cd zstd-wasm/
mkdir bin
make
(cd examples; go run server.go)

click me in http://localhost:5555/ will result in an unexpected error

zstd-helper.js:18 Uncaught TypeError: Module._malloc is not a function
    at zstdCompress (zstd-helper.js:18:26)
    at zstdCompressFloat64 (zstd-helper.js:13:12)
    at HTMLButtonElement.onclick ((index):19:181)

it appears the optimiser sometimes removes these functions