Build fails for wasi-nn feature

[fgrebenac]

When I create new Rust project and add wasmedge-sdk dependency with wasi-nn feature enabled, build fails for aarch64-unknown-linux-gnu target.

[L-jasmine]

Could you provide specific information about the error?

[fgrebenac]

Empty Rust project with only wasmedge-sdk dependency fails to build for aarch64-unknown-linux-gnu target. It fails on wasmedge-sys, with following errors:

   Compiling wasmedge-sys v0.17.5
error[E0277]: a value of type `Vec<*const i8>` cannot be built from an iterator over elements of type `*const u8`
    --> /Users/fgrebenac/.cargo/registry/src/index.crates.io-6f17d22bba15001f/wasmedge-sys-0.17.5/src/plugin.rs:58:72
     |
58   |         let c_strs: Vec<*const i8> = c_args.iter().map(|x| x.as_ptr()).collect();
     |                                                                        ^^^^^^^ value of type `Vec<*const i8>` cannot be built from `std::iter::Iterator<Item=*const u8>`
     |
     = help: the trait `FromIterator<*const u8>` is not implemented for `Vec<*const i8>`
     = help: the trait `FromIterator<*const i8>` is implemented for `Vec<*const i8>`
     = help: for that trait implementation, expected `i8`, found `u8`
note: the method call chain might not have had the expected associated types
    --> /Users/fgrebenac/.cargo/registry/src/index.crates.io-6f17d22bba15001f/wasmedge-sys-0.17.5/src/plugin.rs:58:52
     |
54   |         let c_args: Vec<CString> = preloads
     |                                    -------- this expression has type `Vec<&str>`
55   |             .iter()
     |              ------ `Iterator::Item` is `&&str` here
56   |             .map(|&x| std::ffi::CString::new(x).unwrap())
     |              -------------------------------------------- `Iterator::Item` changed to `CString` here
57   |             .collect();
58   |         let c_strs: Vec<*const i8> = c_args.iter().map(|x| x.as_ptr()).collect();
     |                                             ------ ^^^^^^^^^^^^^^^^^^^ `Iterator::Item` changed to `*const u8` here
     |                                             |
     |                                             `Iterator::Item` is `&CString` here
note: required by a bound in `collect`
    --> /Users/fgrebenac/.rustup/toolchains/stable-aarch64-apple-darwin/lib/rustlib/src/rust/library/core/src/iter/traits/iterator.rs:1999:19
     |
1999 |     fn collect<B: FromIterator<Self::Item>>(self) -> B
     |                   ^^^^^^^^^^^^^^^^^^^^^^^^ required by this bound in `Iterator::collect`

error[E0308]: mismatched types
    --> /Users/fgrebenac/.cargo/registry/src/index.crates.io-6f17d22bba15001f/wasmedge-sys-0.17.5/src/plugin.rs:60:49
     |
60   |         unsafe { ffi::WasmEdge_PluginInitWASINN(c_strs.as_ptr(), len) }
     |                  ------------------------------ ^^^^^^^^^^^^^^^ expected `*const *const u8`, found `*const *const i8`
     |                  |
     |                  arguments to this function are incorrect
     |
     = note: expected raw pointer `*const *const u8`
                found raw pointer `*const *const i8`
note: function defined here
    --> /Users/fgrebenac/Work/Other/wasmedge-test/target/aarch64-unknown-linux-gnu/release/build/wasmedge-sys-75f5617d3409884f/out/wasmedge.rs:2296:12
     |
2296 |     pub fn WasmEdge_PluginInitWASINN(
     |            ^^^^^^^^^^^^^^^^^^^^^^^^^

[L-jasmine]

What version of the SDK are you using?

[fgrebenac]

I tried with wasmedge-sdk versions 0.13.2 and 0.13.5-newapi, and installed WasmEdge version is 0.13.5.

[L-jasmine]

I understand the issue; it’s caused by bindgen treating c_char differently on different platforms (as i8 or u8). I’ll update a new patch to address this problem.

[fgrebenac]

@L-jasmine are there any updates on this issue? I updated WasmEdge library and wasmedge-sdk crate versions to 0.14.0 and still can't get it to compile.

[L-jasmine]

@fgrebenac please try https://github.com/second-state/wasmedge-rust-sdk/tree/0.13.x . I made some updates in this branch, give it a try and see if there are any other issues. If not, I will release it to crates.io. Thank you very much

[fgrebenac]

@L-jasmine thanks for quick reply. Now the mentioned errors are resolved, but there are new ones. Most of them are

error[E0277]: the trait bound `ValType: From<WasmEdge_ValType>` is not satisfied

and

error[E0531]: cannot find unit struct, unit variant or constant `WasmEdge_ValType_I32` in module `ffi`

I'm getting them on my Mac too for the version on 0.13.x branch, but not on the 0.14.0 version. I think that if you merge this one commit from this 0.13.x branch with version 0.14.0 it should compile.

[L-jasmine]

@fgrebenac Most of these errors are due to the fact that the branch matches wasmedge 0.13 and your computer has upgraded to 0.14, I made a response change in a new branch, you try this https://github.com/second-state/wasmedge-rust-sdk/tree/fix/cross-platform

[L-jasmine]

@fgrebenac I updated the version of wasmedge-sys , you can run cargo update and try compiling again

[fgrebenac]

@L-jasmine thank you, it compiles successfully now.