Function setup_ocaml_runtime

pub fn setup_ocaml_runtime()

Set up the OCaml runtime for triggering its signal handler configuration.

Because both the OCaml runtime and Wasmtime set up signal handlers, we must carefully decide when to instantiate them; this function allows us to control when. Wasmtime uses these signal handlers for catching various WebAssembly failures. On certain OSes (e.g. Linux x86_64), the signal handlers interfere, observable as an uncaught SIGSEGV–not even caught by libFuzzer.

This failure can be mitigated by always running Wasmtime second in differential fuzzing. In some cases, however, this is not possible because which engine will execute first is unknown. This function can be explicitly executed first, e.g., during global initialization, to avoid this issue.