Error NETSDK1102 when publishing ASP.NET Core Hosted Blazor WebAssembly App for win-x86 from a win-x64 machine

[IanShaughnessyPG]

Describe the bug

I'm trying to create a win-x86 exe for the ASP.NET Core Host that goes with my Blazor WebAssembly app, but do not want a self-contained host.

Using the default dotnet publish without the --runtime option appears to give me a host that is not self-contained, but does not run on an x86 machine.
Using dotnet publish --runtime win-x86 gives me a self-contained host (which I don't want).
Using dotnet publish --runtime win-x86 --self-contained false fails with error NETSDK1102.

To Reproduce

(Using VisualStudio 2019 and .NET 5.0)

1. Create a new "Blazor WebAssembly App" with the "ASP.NET Core Hosted" option
2. From the command line: dotnet publish --runtime win-x86 --self-contained false
   You will get the following error:

C:\Program Files\dotnet\sdk\5.0.302\Sdks\Microsoft.NET.Sdk\targets\Microsoft.NET.ILLink.targets(143,5): error NETSDK1102: Optimizing assemblies for size is not supported for the selected publish configuration. Please ensure that you are publishing a self-contained app.

Exceptions (if any)

Further technical details

• Include the output of dotnet --info

.NET SDK (reflecting any global.json):
 Version:   5.0.302
 Commit:    c005824e35

Runtime Environment:
 OS Name:     Windows
 OS Version:  10.0.18362
 OS Platform: Windows
 RID:         win10-x64
 Base Path:   C:\Program Files\dotnet\sdk\5.0.302\

Host (useful for support):
  Version: 5.0.8
  Commit:  35964c9215

.NET SDKs installed:
  2.1.202 [C:\Program Files\dotnet\sdk]
  2.1.524 [C:\Program Files\dotnet\sdk]
  5.0.102 [C:\Program Files\dotnet\sdk]
  5.0.201 [C:\Program Files\dotnet\sdk]
  5.0.302 [C:\Program Files\dotnet\sdk]

.NET runtimes installed:
  Microsoft.AspNetCore.All 2.1.13 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.All]
  Microsoft.AspNetCore.All 2.1.18 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.All]
  Microsoft.AspNetCore.All 2.1.19 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.All]
  Microsoft.AspNetCore.All 2.1.20 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.All]
  Microsoft.AspNetCore.All 2.1.22 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.All]
  Microsoft.AspNetCore.All 2.1.23 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.All]
  Microsoft.AspNetCore.All 2.1.24 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.All]
  Microsoft.AspNetCore.All 2.1.28 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.All]
  Microsoft.AspNetCore.App 2.1.13 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.App]
  Microsoft.AspNetCore.App 2.1.18 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.App]
  Microsoft.AspNetCore.App 2.1.19 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.App]
  Microsoft.AspNetCore.App 2.1.20 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.App]
  Microsoft.AspNetCore.App 2.1.22 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.App]
  Microsoft.AspNetCore.App 2.1.23 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.App]
  Microsoft.AspNetCore.App 2.1.24 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.App]
  Microsoft.AspNetCore.App 2.1.28 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.App]
  Microsoft.AspNetCore.App 3.1.17 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.App]
  Microsoft.AspNetCore.App 5.0.2 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.App]
  Microsoft.AspNetCore.App 5.0.8 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.App]
  Microsoft.NETCore.App 2.0.9 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
  Microsoft.NETCore.App 2.1.13 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
  Microsoft.NETCore.App 2.1.18 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
  Microsoft.NETCore.App 2.1.19 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
  Microsoft.NETCore.App 2.1.20 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
  Microsoft.NETCore.App 2.1.22 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
  Microsoft.NETCore.App 2.1.23 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
  Microsoft.NETCore.App 2.1.24 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
  Microsoft.NETCore.App 2.1.26 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
  Microsoft.NETCore.App 2.1.28 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
  Microsoft.NETCore.App 3.1.17 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
  Microsoft.NETCore.App 5.0.2 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
  Microsoft.NETCore.App 5.0.8 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
  Microsoft.WindowsDesktop.App 3.1.17 [C:\Program Files\dotnet\shared\Microsoft.WindowsDesktop.App]
  Microsoft.WindowsDesktop.App 5.0.2 [C:\Program Files\dotnet\shared\Microsoft.WindowsDesktop.App]
  Microsoft.WindowsDesktop.App 5.0.8 [C:\Program Files\dotnet\shared\Microsoft.WindowsDesktop.App]

• The IDE (VS / VS Code/ VS4Mac) you're running on, and its version

Microsoft Visual Studio Enterprise 2019
Version 16.10.4

[tpitman]

I am having a related issue trying to build an linux/amd64 based docker image on an M1 mac.

I started with an issue in the dotnet/sdk group here and was told to move it to nuget/Home (NuGet/Home#12329) because it has to do with dotnet restore not running right. Then they told me to go to the dotnet/docker group (dotnet/dotnet-docker#4285) because they thought it had to do with docker specifically.

Part of trying to get a solution in that issue involved telling the system to not make a self contained app and other settings like this:

dotnet publish "WebServer.csproj" -c Release -o /app/publish -r linux-x64 --self-contained false /p:UseAppHost=false /p:PublishTrimmed=false

This is a Blazor app that has 2 UI projects and several api projects. The 2 web projects are the server and the UI code.

When I try to run the above command I get this error and the docker group doesn't know why:

error MSB4044: The "ComputeBlazorPublishAssets" task was not given a value for the required parameter "DotNetJsVersion". [/src/Web/Web.csproj]

The docker group said I have to build this as self contained. If I omit the /p:PublishTrimmed=false, then I get an error about not being able to trim an app that isn't self contained.

What do I do now?

[marcpopMSFT]

Old issue triage: The default now is to not be self-contained with specifying a RID so likely you won't get into this situation again.