bytecode compatibility

[mimoo]

I'm trying to run ocamldebug on some OCaml code that is linked to a Rust library (using ocaml-rs). I need to build to the bytecode format before I can do that with dune build some/path.bc but I get the following error:

Error: Error on dynamically loaded library: ./src/lib/crypto/kimchi_bindings/stubs/dllwires_15_stubs.so: Truncated file

I'm wondering if there's a way to make this work? Or if this is because FFI can't happen due to the bytecode format of OCaml

[tizoc]

Hi, just pinged you. I had this same issue some time ago, but it is unrelated to ocaml-rs. Just copy the file manually after a regular build and before you try to build the bytecode program:

cp ./_build/cargo_kimchi_bindgen/debug/libwires_15_stubs.so src/lib/crypto/kimchi_bindings/stubs/dllwires_15_stubs.so

[mimoo]

ah, Imma try that!

A coworker told me that this change also made it work: MinaProtocol/mina@b3ae083 but that it wouldn't work on mac

[mimoo]

btw I think I don't have .so because I'm on mac?

❯ ls ./_build/cargo_kimchi_stubs/release 
build                  examples               libwires_15_stubs.a    libwires_15_stubs.rlib wires_15_stubs.d
deps                   incremental            libwires_15_stubs.d    wires_15_stubs

[tizoc]

hmmm weird, I would expect to see a .dylib instead, but it is not there.

And the docs confirm that the "cdylib" crate type should produce that (EDIT: that change in the commit you linked was reverted later, but you need that "cdylib" there, I had to add it a while back when I hit the same issue as you)

--crate-type=cdylib, #![crate_type = "cdylib"] - A dynamic system library will be produced. This is used when compiling a dynamic library to be loaded from another language. This output type will create *.so files on Linux, *.dylib files on macOS, and *.dll files on Windows.