Stream: wit-bindgen

Topic: ✔ ComponentEncoder and fd_advise

Scott Waye (Aug 26 2023 at 18:56):

Hi, When I attempt to encode my runtime test wasm for c# with

        let component = ComponentEncoder::default()
            .module(module.as_slice())
            .expect("pull custom sections from module")
            .validate(true)
            .adapter("wasi_snapshot_preview1", &wasi_adapter)
            .expect("adapter failed to get loaded")
            .encode()
            .expect(&format!(
                "module {:?} can be translated to a component",
                out_wasm
            ));

I'm getting error

"C:\\github\\wit-bindgen-csharp\\target\\runtime-tests\\numbers\\csharp-numbers\\csharp-wasm\\csharp-wasm.wasm"
thread 'numbers::run' panicked at 'module "C:\\github\\wit-bindgen-csharp\\target\\runtime-tests\\numbers\\csharp-numbers\\csharp-wasm" can be translated to a component: failed to reduce input adapter module to its minimal size

Caused by:
    adapter module does not have export `fd_advise`', tests\runtime\main.rs:695:14

I understand that wasi provides a fd_advise, is that not the case?

Alex Crichton (Aug 28 2023 at 14:15):

Are you sure you're using the right adapter? The fd_advise function is present in the adapter provided by Wasmtime, but if you're using a different adapter then you may need to make sure that function is present in the custom adapter

Scott Waye (Aug 28 2023 at 14:19):

I'm using the one from wit-bindgen-csharp\\target\\debug\\build\\test-artifacts-477de5d9b736cf4f\\out\\wasm32-unknown-unknown/release/wasi_snapshot_preview1.wasm How do I know from where that originates?

Alex Crichton (Aug 28 2023 at 14:20):

I believe that's project-specific build/configuration options, which I'm not familiar with in this case

Scott Waye (Aug 28 2023 at 14:26):

Would https://github.com/bytecodealliance/preview2-prototyping/releases/tag/latest by the right place for the latest wit-bindgen?

Scott Waye (Aug 28 2023 at 16:24):

Guess not quite as there is now a version mismatch

component-type version 2 does not match supported version 3', tests\runtime\main.rs:693:14

Scott Waye (Aug 28 2023 at 16:24):

Is wit-bindgen already on version 3?

Lann Martin (Aug 28 2023 at 16:59):

All (?) language toolchains currently generate core modules rather than components. In order to allow a tool like wasm-tools component new to generate a component from one of these core modules, wit-bindgen embeds type metadata in its generated code. The current version of that metadata is indeed 3.

Scott Waye (Aug 28 2023 at 17:15):

Doesn't look like there is a preview3-prototyping repo, where I could download the adpaters Should I build them from source?

Peter Huene (Aug 28 2023 at 17:16):

Currently the adapters are built as part of the wasmtime repo and are available in the releases: https://github.com/bytecodealliance/wasmtime/releases

Scott Waye (Aug 28 2023 at 17:23):

Thanks, looks like I will need to export a _start which I don't have currently perhaps because I wasm-ld with -Wl,--no-entry

Scott Waye (Aug 28 2023 at 17:42):

Thought wasm-ld would add that for exec-model=command , but guess not

Alex Crichton (Aug 28 2023 at 18:15):

If you're getting an error about _start you'll want the *.reactor.wasm instead of the *.command.wasm

Scott Waye (Aug 28 2023 at 18:57):

Thanks that gets me to

Error: import `wasi:clocks/wall-clock` has the wrong type

Was a new SDK released?

Alex Crichton (Aug 28 2023 at 19:02):

is that error coming from wasmtime? Or a different runtime?

There's not really releases in a discrete sense for the component model right now so whether or now a new SDK release depends on what you mean, but the answer is probably "yes" for what you're curious about (aka WASI interfaces changed since whatever is generating the error last updated to)

Scott Waye (Aug 28 2023 at 19:50):

its the wit-bindgen runtime test

Alex Crichton (Aug 28 2023 at 19:51):

oh hm, is it possible to share a reproduction?

Scott Waye (Aug 28 2023 at 19:59):

I'm not sure, its not my repo. But let me check the wall-clock/now function in the module wasm and the adapter

Scott Waye (Aug 28 2023 at 20:14):

The adapter does look a bit odd compared to https://github.com/bytecodealliance/wasmtime/blob/8efcb9851602287fd07a1a1e91501f51f2653d7e/crates/wasi/wit/deps/clocks/wall-clock.wit#L37

Scott Waye (Aug 28 2023 at 20:15):

(import "wasi:clocks/wall-clock" "now" (func $_ZN22wasi_snapshot_preview18bindings4wasi6clocks10wall_clock3now10wit_import17h612125935ddec421E (type 0)))

and

  (type (;0;) (func (param i32)))

Scott Waye (Aug 28 2023 at 20:16):

But maybe that's how it handles the complex type, it returns it via a pointer

Alex Crichton (Aug 28 2023 at 20:18):

yeah that's the canonical abi for returning larger-than-a-primitive types

Scott Waye (Aug 29 2023 at 12:36):

I think I have this https://github.com/bytecodealliance/wasmtime/issues/6523, the error message is just not that clear, says the type is wrong when it seems like it should be that the type is not found

Scott Waye (Aug 29 2023 at 12:57):

but with wasmtime_wasi 12 I don't think there is a preview2::wasi

Scott Waye (Aug 29 2023 at 13:47):

I can attempt to add the whole commands, but it requires a different generic instance of the linker:

error[E0277]: the trait bound `Wasi<numbers::MyImports>: WasiView` is not satisfied
  --> tests\runtime\numbers.rs:91:61
   |
91 |             wasmtime_wasi::preview2::command::add_to_linker(linker);
   |             ----------------------------------------------- ^^^^^^ the trait `WasiView` is not implemented for `Wasi<numbers::MyImports>`
   |             |
   |             required by a bound introduced by this call
   |

Alex Crichton (Aug 29 2023 at 13:52):

How was the error above printed? If that's the only output you got then that's a bug in the error printing where it didn't print the full context.

Alex Crichton (Aug 29 2023 at 13:52):

The WASI support for the component model is in a shaky state and you're sort of on your own to get things working right now

Alex Crichton (Aug 29 2023 at 13:52):

it has not been in a "finished" state in wasmtime to-date yet

Alex Crichton (Aug 29 2023 at 13:53):

so it requires chasing down changes between commits and adapter versions and such

Scott Waye (Aug 29 2023 at 13:56):

Ok, understood. This was printed by cargo test numbers -p wit-bindgen-cli --no-default-features -F csharp

Scott Waye (Aug 29 2023 at 13:56):

Oh sorry you mean the type mismatch

Scott Waye (Aug 29 2023 at 13:58):

But the answer is the same, from that command line and appears from the line let (exports, _) = instantiate(&mut store, &component, &linker)?;

Scott Waye (Aug 29 2023 at 13:59):

I did have it working from a prototype, just not from the runtime test. I can investigate the trait difference and see if there is a way round that

Scott Waye (Aug 29 2023 at 14:06):

---- numbers::run stdout ----
wasi adapter = "C:\\github\\wit-bindgen-csharp\\target\\debug\\build\\test-artifacts-477de5d9b736cf4f\\out\\wasm32-unknown-unknown/release/wasi_snapshot_preview1.wasm"
"dotnet" "publish" "C:\\github\\wit-bindgen-csharp\\target\\runtime-tests\\numbers\\csharp-numbers\\Numbers.csproj" "-r" "wasi-wasm" "-c" "Debug" "/p:PlatformTarget=AnyCPU" "/p:MSBuildEnableWorkloadResolver=false" "--self-contained" "/p:UseAppHost=false" "-o" "C:\\github\\wit-bindgen-csharp\\target\\runtime-tests\\numbers\\csharp-numbers\\csharp-wasm"
"C:\\github\\wit-bindgen-csharp\\target\\runtime-tests\\numbers\\csharp-numbers\\csharp-wasm\\csharp-wasm.wasm"
testing
add to linker
testwasi add to linker
instantiate
Error: import `wasi:clocks/wall-clock` has the wrong type

Caused by:
    0: instance export `now` has the wrong type
    1: expected func found nothing


failures:
    numbers::run

test result: FAILED. 0 passed; 1 failed; 0 ignored; 0 measured; 8 filtered out; finished in 57.55s

error: test failed, to rerun pass `-p wit-bindgen-cli --test runtime`

Is the whole output, reading it closer, I see it did also say "expected func found nothing", which could be the underlying cause although it could do with being less terse, or at least a comma, "epxected func, found nothing"

Alex Crichton (Aug 29 2023 at 14:09):

ah ok that's good to know! Just wanted to make sure context wasn't being left out by accident

Alex Crichton (Aug 29 2023 at 14:10):

and yeah the error message here is definitely not great

Scott Waye (Aug 31 2023 at 01:19):

I have made a bit of progress I think ! I think I need async bindgen macros because I have this error

thread 'numbers::run' panicked at 'must use async instantiation when async support is enabled', C:\Users\scott\.cargo\registry\src\index.crates.io-6f17d22bba15001f\wasmtime-12.0.0\src\component\linker.rs:211:9

The macro is

wasmtime::component::bindgen!(in "tests/runtime/numbers");

Is there a way to make that generate an async instantiate?

Scott Waye (Aug 31 2023 at 01:38):

Ah, this seems to be a bit of a rabbit hole, I can enable async with

wasmtime::component::bindgen!({
    path: "tests/runtime/numbers",
    async : true
});

But then it seems all the test methods need to be converted to async?

error[E0195]: lifetime parameters or bounds on method `roundtrip_u8` do not match the trait declaration
  --> tests\runtime\numbers.rs:15:20
   |
4  | / wasmtime::component::bindgen!({
5  | |     path: "tests/runtime/numbers",
6  | |     async : true
7  | | });
   | |  -
   | |  |
   | |__lifetimes in impl do not match this method in trait
   |    this bound might be missing in the impl
...
15 |       fn roundtrip_u8(&mut self, val: u8) -> Result<u8> {
   |                      ^ lifetimes do not match method in trait

Alex Crichton (Aug 31 2023 at 04:48):

Yes everything is async by default with that configuration. You can replace true with a curly braced map or list to only have some functions be async. I forget what the exact syntax is

Alex Crichton (Aug 31 2023 at 14:02):

Ah looks like I'm thinking of a feature of wiggle, not bindgen!, so let me go add the feature to bindgen!

Scott Waye (Aug 31 2023 at 14:16):

Ah, yes it seems to just want a bool at present, thanks!

Alex Crichton (Aug 31 2023 at 14:30):

I've opened https://github.com/bytecodealliance/wasmtime/pull/6942 to add new configuration for making some imports sync

Scott Waye (Aug 31 2023 at 15:12):

Thank you!

Scott Waye (Sep 01 2023 at 20:18):

Will close this as I think I just need to work aroumd the async exports now

Scott Waye (Sep 01 2023 at 20:18):

THanks

Notification Bot (Sep 01 2023 at 20:18):

Scott Waye has marked this topic as resolved.

Last updated: Nov 22 2024 at 16:03 UTC