wasmtime demo command fail to execute markdown.wasm

[whalelephant]

Following the demo in this youtube video with a clone of this directory, I was unable to use wasmtime to run wasmtime markdown.wasm --invoke render "# Hello"

wasmtime version 0.9.0

Error:

~/wasmtime-demos/markdown(master) » wasmtime markdown.wasm --invoke render "# Hello" 
Error: failed to run main module `markdown.wasm`

Caused by:
    func type returns multiple values (at offset 47)

[tomasol]

Seems to be duplicate of #2

[alexcrichton]

I'm going to now that we've temporarily removed interface types support, but stay tuned to bytecodealliance/wasmtime#677 for future updates!