How to make rust crate with C lib dependency "wasm32-unknown-unknown compatible"

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Hi, I have problem about C, Rust and WASM. There is a C lib called libspot, which implement an algorithm with pure C(without c stdlib). I wrap it by Rust ffi, and built a lib crate named with libspot too(GitHub - shenxiangzhuang/libspot-rs: A Rust wrapper for the libspot). To be clear, let's call the wrapper crate with libspot-rs(just as repo name). Based on the libspot-rs, I built another lib crate, let's just call it X.

The problem is that I can not add wasm binding for the X crate, because it dependents on libspot-rs, and libspot-rs use C lib libspot by ffi.

All I want is that use libspot-rs as a regular pure rust crate and can add wasm binding by wasm-bindgen normally. And I want to know how to do this. Any suggestion would be greatly appreciated!

For references: the orignal libspot c lib already has a wasm binding and has beed published to npm.

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Just a silly idea: maybe you could convert libpost to Rust with C2Rust?

I'm very curious what the answer to this will be.

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Or maybe, another solution would be to use the existing libspot WASM binding, and calling it from your generated WASM code? Not sure how that could be possible. Can a WASM program call another WASM blob? If so, that might be the solution :thinking:

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Provided that you have a C compiler capable of compiling for wasm (eg clang), it should be possible to just use C code from wasm32-unknown-unknown like you would for native platforms starting from rustc 1.89 (which is currently in beta). Before that there were ABI incompatibilities: Remove wasm legacy abi by bjorn3 · Pull Request #133952 · rust-lang/rust · GitHub

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Thanks for your suggestion. Could you please provide some tutorial about this? I build with rust nightly and it build well, but the generated js file first line with import * as __wbg_star0 from 'env';, which lead to the fellowing error:

Uncaught TypeError: Failed to resolve module specifier "env". Relative references must start with either "/", "./", or "../".

It seems switch to nightly doesn't change the error. Is there any suggestion about this error?

Ps: the wasm-bindgen version is v0.2.100, I don't know if the rustc 1.89 version feature need wasm-bindgen's support or not.

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I think the original C implementation is pretty solid, so I won't re-impl it if there has other choice:)

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Yes, this should be a solution in a way, but I don't find related resources about this.

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