wasm: panic: runtime error: slice out of range about tinygo HOT 2 CLOSED

Fixed. The compiler was inserting a runtime slice bounds check based on the length of the slice instead of the capacity - as it should have been according to the spec. Apparently *bytes.Buffer reslices an internal buffer outside of the length but inside the capacity, surfacing this bug.

I've also made a few other changes to the compiler that should make it easier to detect this error (by executing a WebAssembly unreachable instruction on such errors) and I made sure the custom Docker image with a custom wasm.syms file should not be necessary anymore. You can see the build status here: https://hub.docker.com/r/tinygo/tinygo/builds/

from tinygo.

Thanks again for the report, these are the kind of bugs that need to be fixed to make TinyGo stable.

from tinygo.