WebAssembly multithreading sample breaks on .NET 8 preview 1 (missing Microsoft.NET.ILLink.Tasks)

[joelverhagen]

Description

I tried updating my wasm mutlithreading sample from here:
https://devblogs.microsoft.com/dotnet/asp-net-core-updates-in-dotnet-7-rc-2/#webassembly-multithreading-experimental

I got the following error: Unable to find package Microsoft.NET.ILLink.Tasks

  Determining projects to restore...
  Writing C:\Users\joelv\AppData\Local\Temp\tmp1nyqnz.tmp
info : X.509 certificate chain validation will use the default trust store selected by .NET.
info : X.509 certificate chain validation will use the default trust store selected by .NET.
info : Adding PackageReference for package 'Microsoft.NET.WebAssembly.Threading' into project 'C:\Users\joelv\Desktop\wasmthread\wasmthread.csproj'.
info :   CACHE https://api.nuget.org/v3/registration5-gz-semver2/microsoft.net.webassembly.threading/index.json
info : Restoring packages for C:\Users\joelv\Desktop\wasmthread\wasmthread.csproj...
info :   GET https://api.nuget.org/v3-flatcontainer/microsoft.net.illink.tasks/index.json
info :   NotFound https://api.nuget.org/v3-flatcontainer/microsoft.net.illink.tasks/index.json 269ms
error: NU1101: Unable to find package Microsoft.NET.ILLink.Tasks. No packages exist with this id in source(s): C:\Program Files\dotnet\library-packs, Microsoft Visual Studio Offline Packages, nuget.org
error: Package 'Microsoft.NET.WebAssembly.Threading' is incompatible with 'all' frameworks in project 'C:\Users\joelv\Desktop\wasmthread\wasmthread.csproj'.

Repro steps (as directed in the blog post)

1. dotnet workload install wasm-experimental
2. dotnet new wasmbrowser
3. dotnet add package --prerelease Microsoft.NET.WebAssembly.Threading

Configuration

Regression?

Yes. This worked on .NET 7.

Other information

.NET SDK:
 Version:   8.0.100-preview.1.23115.2
 Commit:    913e4679b3

Runtime Environment:
 OS Name:     Windows
 OS Version:  10.0.22621
 OS Platform: Windows
 RID:         win10-x64
 Base Path:   C:\Program Files\dotnet\sdk\8.0.100-preview.1.23115.2\

Host:
  Version:      8.0.0-preview.1.23110.8
  Architecture: x64
  Commit:       7deac7d6da

.NET SDKs installed:
...
  7.0.102 [C:\Program Files\dotnet\sdk]
  7.0.200-preview.22628.1 [C:\Program Files\dotnet\sdk]
  8.0.100-preview.1.23115.2 [C:\Program Files\dotnet\sdk]

.NET runtimes installed:
...
  Microsoft.AspNetCore.App 7.0.0 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.App]
  Microsoft.AspNetCore.App 7.0.2 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.App]
  Microsoft.AspNetCore.App 8.0.0-preview.1.23112.2 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.App]
...
  Microsoft.NETCore.App 7.0.0 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
  Microsoft.NETCore.App 7.0.2 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
  Microsoft.NETCore.App 8.0.0-preview.1.23110.8 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
...
  Microsoft.WindowsDesktop.App 7.0.0 [C:\Program Files\dotnet\shared\Microsoft.WindowsDesktop.App]
  Microsoft.WindowsDesktop.App 7.0.2 [C:\Program Files\dotnet\shared\Microsoft.WindowsDesktop.App]
  Microsoft.WindowsDesktop.App 8.0.0-preview.1.23112.2 [C:\Program Files\dotnet\shared\Microsoft.WindowsDesktop.App]

[joelverhagen]

This appears to be resolved. The package was published as of 3 hours ago.
https://www.nuget.org/packages/Microsoft.NET.ILLink.Tasks/8.0.100-1.23067.1

[joelverhagen]

For the record, the whole sample works as it did on .NET 7 (as far as I can tell). Awesome!