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VS 16.8 Preview 3 breaks Source Generators

See original GitHub issue

Version Used:

Version 16.8.0 Preview 3.0, updated from Preview 2.0 via VS installer.

Steps to Reproduce:

Use SG Sample from roslyn-sdk
Update all packages
Build

Expected Behavior:

No error

Actual Behavior:

CSC : warning CS8032: An instance of analyzer SourceGeneratorSamples.HelloWorldGenerator cannot be created from ...\roslyn-sdk\artifacts\bin\SourceGeneratorSamples\Debug\netstandard2.0\SourceGeneratorSamples.dll : Could not load file or assembly 'Microsoft.CodeAnalysis, Version=3.8.0.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35' or one of its dependencies.

-> Same error for all SG

Reverting Microsoft.CodeAnalysis 3.8.0-2.final to 3.7.0 solves the problem somehow.

Updates:

Microsoft.CodeAnalysis.Common.3.8.0-2.final -> Microsoft.CodeAnalysis.Common.3.7.0 Microsoft.CodeAnalysis.CSharp.3.8.0-2.final -> Microsoft.CodeAnalysis.CSharp.3.7.0 System.Collections.Immutable.5.0.0-preview.8.20371.14 -> System.Collections.Immutable.1.5.0 System.Reflection.Metadata.5.0.0-preview.8.20371.14 -> System.Reflection.Metadata.1.6.0

Tried the same for the Blazor problem demo project: blazor-with-source-generators-poc

But no luck here when reverting Microsoft.CodeAnalysis 3.8.0-2.final to 3.7.0. Even the Console App build fails already:

CSC : warning CS8032: An instance of analyzer SourceGeneratorSamples.HelloWorldGenerator cannot be created from ...\blazor-with-source-generators-poc\src\SourceGen\bin\Debug\netstandard2.0\SourceGen.dll : Method 'Initialize' in type 'SourceGeneratorSamples.HelloWorldGenerator' from assembly 'SourceGen, Version=1.0.0.0, Culture=neutral, PublicKeyToken=null' does not have an implementation..

CS0103	The name 'HelloWorldGenerated' does not exist in the current context	ConsoleApp1

Issue Analytics

State:
Created 3 years ago
Comments:11 (6 by maintainers)

Top GitHub Comments

2reactions

jmarolfcommented, Sep 15, 2020

@chsienki I assume we are going to publish the preview 3 nuget packages?

2reactions

b-straubcommented, Sep 15, 2020

Sure this works now, but not without adding an additional preview source! Microsoft.CodeAnalysis.CSharp needs to be version 3.8.0-4.20464.1 from:

<add key="dotnet-tools" value="https://pkgs.dev.azure.com/dnceng/public/_packaging/dotnet-tools/nuget/v3/index.json" />

and not the shipped one from VS 16.8 p3 with dotnet-sdk-5.0.100-rc.1.20452.10.

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