workload wasi-experimental - is this where it's supported? Build tool issue on MacOS M1 - Error MSB4062 : Task could not be loaded from the assembly - WasmAppBuilder.dll.

[Simonl9l]

It seems dotnet workloads is an area of dotnet that is not, to many, well known about it seems. If this is the wrong place, please can you let me know?

I'm running on Apple Silicon (M1/Arm64).

I'm trying to use a project that is dependent on wasi-experimental and the wasi-sdk, and have followed the instruction to instal the MacOs (universal binaries).

It seem that if I follow all this correctly wasi-experimental is looking for the wasi-sdk in /Users/{profile}/.wasi-sdk/wasi-sdk-16.0 and, per the project maintainer, putting the bin, lib, share of the v20 sdk in this folder "works on Windows". I have installed v20 the same way.

I also have the WASI_SDK_PATH=/Users/{profile}/.wasi-sdk/wasi-sdk-16.0

If I try and build the project I get the following error:

0>Wasi.Sdk.targets(102,3): Error MSB4062 : The "Microsoft.WebAssembly.Build.Tasks.WasmResolveAssemblyDependencies" task could not be loaded from the assembly /usr/local/share/dotnet/packs/Microsoft.NET.Runtime.WebAssembly.Wasi.Sdk/8.0.2/Sdk/../tasks/net8.0/WasmAppBuilder.dll.  
Confirm that the <UsingTask> declaration is correct, that the assembly and all its dependencies are available, and that the task contains a public class that implements Microsoft.Build.Framework.ITask.
0>------- Finished building project: WasiInterfacePlugin. Succeeded: False. Errors: 1. Warnings: 0

Any clues, directions or hits are appreciated as this has me dead in the water.

[maraf]

It works with my setup

I have install wasi-experimental workload, downloaded (latest) WASI SDK and put it in /Users/marekfisera/Bin/wasi-sdk-21.0, then set WASI_SDK_PATH

export WASI_SDK_PATH=/Users/marekfisera/Bin/wasi-sdk-21.0

Now I can build an app generated from wasi-console template with native relink.

Can you do build in your environment and share a binlog (dotnet build -bl)?

[enghch]

I expected there to be a [my project].wasm file in addition to the dotnet.wasm file. That's how it worked with .NET 8. It would merge my code with the dotnet.wasm code into a single .wasm file. One directory up, I see a [my project].dll file. I think that's the file that should have been converted to wasm. (I just went back to Preview 6 and it appears to have the same behavior.)

The reason I switched from .NET 8 is to 9 is that 8 didn't support the [UnmanagedCallersOnly] attribute. It didn't produce any exports.

[ReneeGA2020]

It is supposed to have a dotnet.wasm by default. If you want to generate single project.wasm file, you will have to add <WasmSingleFileBundle>true</WasmSingleFileBundle> into you project file. Also you may have to update your wasmtime and wasi-sdk to the latest versions (24 for now)

[maraf]

@enghch

    Directory: ..../WasiConsole90/bin/Debug/net9.0/wasi-wasm/AppBundle

drwxr-xr-x marekfisera      staff              02.09.2024 10:16             64 tmp
-rw-r--r-- marekfisera      staff              02.09.2024 10:16            456 node.mjs
-rwxr-xr-x marekfisera      staff              02.09.2024 10:16             82 run-node.sh
-rwxr-xr-x marekfisera      staff              02.09.2024 10:16             35 run-wasmtime.sh
-rw-r--r-- marekfisera      staff              02.09.2024 10:16           1853 WasiConsole90.runtimeconfig.json
-rwxr-xr-x marekfisera      staff              02.09.2024 10:16       33866280 WasiConsole90.wasm

This is the expected output for single file. You are right that dotnet.wasm should be there, I misread it.

<Project Sdk="Microsoft.NET.Sdk">
  <PropertyGroup>
    <TargetFramework>net9.0</TargetFramework>
    <RuntimeIdentifier>wasi-wasm</RuntimeIdentifier>
    <OutputType>Exe</OutputType>
    <PublishTrimmed>true</PublishTrimmed>
+    <WasmSingleFileBundle>true</WasmSingleFileBundle>
  </PropertyGroup>
</Project>

This is my csproj, the app is generated from wasiconsole template and WasmSingleFileBundle=true is added. This behavior is the same as in 8.

[enghch]

Thank you! After much experimenting, I finally got this working on .NET 9 Preview 6. I needed to set the OutputType to Exe (I had it as Library). BUT, this still doesn't work for me on Preview 7. On Preview 7, even with the WasmSingleFileBundle=true, it doesn't generate the single wasm file. It just dumps the copy of the dotnet.wasm file and that's all. But I'm unblocked for the moment by using Preview 6!

[maraf]

More details here #106350 (comment).