Files
wasmtime/crates/fuzzing/wasm-spec-interpreter
Chris Fallin b2bcdd13ec Spec-interpreter fuzzing: check out fuzzing branch of our mirror. (#3222)
In #3186, we found an issue that requires patching the spec interpreter
for now. Our plan is to have a `fuzzing` branch in our spec-repo mirror
that lets us make these fixes locally before they are upstreamed.
This PR updates the build script for the spec-interpreter wrapper
crate to clone this particular `fuzzing` branch instead of the main
branch.
2021-08-20 12:54:52 -05:00
..

wasm-spec-interpreter

This project shows how to use ocaml-interop to call into the Wasm spec interpreter. There are several steps to making this work:

  • building the OCaml Wasm spec interpreter as a static library
  • building a Rust-to-OCaml FFI bridge using ocaml-interop and a custom OCaml wrapper
  • linking both things into a Rust crate

Dependencies

This crate only builds in an environment with:

  • make (the Wasm spec interpreter uses a Makefile)
  • ocamlopt, ocamlbuild (available with, e.g., dnf install ocaml)
  • Linux tools (e.g. ar); currently it is easiest to build the static libraries in a single environment but this could be fixed in the future (TODO)

Remember to retrieve the Wasm spec submodule:

git clone ... --recursive

Build

RUSTFLAGS=--cfg=fuzzing cargo build

Use FFI_LIB_DIR=path/to/lib/... to specify a different location for the static library (this is mainly for debugging). If the --cfg=fuzzing configuration is not provided, this crate will build successfully but fail at runtime.

Test

RUSTFLAGS=--cfg=fuzzing cargo test