dotnet · AlekseyTs · Jul 21, 2025 · Jul 8, 2025 · Jul 8, 2025 · Jul 8, 2025
diff --git a/.vscode/tasks.json b/.vscode/tasks.json
@@ -103,6 +103,7 @@
         "command": "dotnet",
         "args": [
           "build",
+          "-p:InnerTargets=CopyFilesForDebugging",
           "-p:GenerateFullPaths=true",
           "${workspaceFolder}/src/NuGet/Microsoft.Net.Compilers.Toolset/AnyCpu/Microsoft.Net.Compilers.Toolset.Package.csproj"
         ],

diff --git a/Compilers.slnf b/Compilers.slnf
@@ -53,6 +53,7 @@
       "src\\ExpressionEvaluator\\Core\\Source\\ExpressionCompiler\\Microsoft.CodeAnalysis.ExpressionCompiler.csproj",
       "src\\ExpressionEvaluator\\VisualBasic\\Source\\ExpressionCompiler\\Microsoft.CodeAnalysis.VisualBasic.ExpressionCompiler.vbproj",
       "src\\Interactive\\csi\\csi.csproj",
+      "src\\NuGet\\Microsoft.CodeAnalysis.BuildClient.Package\\Microsoft.CodeAnalysis.BuildClient.Package.csproj",
       "src\\NuGet\\Microsoft.CodeAnalysis.Compilers.Package\\Microsoft.CodeAnalysis.Compilers.Package.csproj",
       "src\\NuGet\\Microsoft.CodeAnalysis.Package\\Microsoft.CodeAnalysis.Package.csproj",
       "src\\NuGet\\Microsoft.Net.Compilers.Toolset\\AnyCpu\\Microsoft.Net.Compilers.Toolset.Package.csproj",

diff --git a/NuGet.config b/NuGet.config
@@ -5,13 +5,16 @@
     <clear />
     <add key="dotnet-eng" value="https://pkgs.dev.azure.com/dnceng/public/_packaging/dotnet-eng/nuget/v3/index.json" />
     <add key="dotnet-tools" value="https://pkgs.dev.azure.com/dnceng/public/_packaging/dotnet-tools/nuget/v3/index.json" />
+    <!-- We need dotnet6 because BuildValidator depends on runtime.{platform}.Microsoft.NETCore.ILDAsm (>= 6.0.0-rtm.21518.12) -->
     <add key="dotnet6" value="https://pkgs.dev.azure.com/dnceng/public/_packaging/dotnet6/nuget/v3/index.json" />
-    <add key="dotnet7" value="https://pkgs.dev.azure.com/dnceng/public/_packaging/dotnet7/nuget/v3/index.json" />
+    <!-- We need dotnet7-transport because we depend on Microsoft.CodeAnalysis.PerformanceSensitiveAnalyzers (>= 3.3.4-beta1.22504.1) -->
     <add key="dotnet7-transport" value="https://pkgs.dev.azure.com/dnceng/public/_packaging/dotnet7-transport/nuget/v3/index.json" />
+    <!-- We need dotnet8 because we depend on Microsoft.CodeAnalysis.NetAnalyzers (>= 8.0.0-preview.23468.1) -->
     <add key="dotnet8" value="https://pkgs.dev.azure.com/dnceng/public/_packaging/dotnet8/nuget/v3/index.json" />
-    <add key="dotnet8-transport" value="https://pkgs.dev.azure.com/dnceng/public/_packaging/dotnet8-transport/nuget/v3/index.json" />
+    <!-- We need dotnet9 because we depend on Roslyn.Diagnostics.Analyzers (>= 3.11.0-beta1.24081.1)-->
     <add key="dotnet9" value="https://pkgs.dev.azure.com/dnceng/public/_packaging/dotnet9/nuget/v3/index.json" />
-    <add key="dotnet9-transport" value="https://pkgs.dev.azure.com/dnceng/public/_packaging/dotnet9-transport/nuget/v3/index.json" />
+    <add key="dotnet10" value="https://pkgs.dev.azure.com/dnceng/public/_packaging/dotnet10/nuget/v3/index.json" />
+    <add key="dotnet10-transport" value="https://pkgs.dev.azure.com/dnceng/public/_packaging/dotnet10-transport/nuget/v3/index.json" />
     <add key="dotnet-public" value="https://pkgs.dev.azure.com/dnceng/public/_packaging/dotnet-public/nuget/v3/index.json" />
     <add key="dotnet-libraries" value="https://pkgs.dev.azure.com/dnceng/public/_packaging/dotnet-libraries/nuget/v3/index.json" />
     <add key="dotnet-libraries-transport" value="https://pkgs.dev.azure.com/dnceng/public/_packaging/dotnet-libraries-transport/nuget/v3/index.json" />

diff --git a/Roslyn.sln b/Roslyn.sln
@@ -22,7 +22,7 @@ resources:
     name: internal/dotnet-roslyn
     ref: $(Build.SourceBranch)
     trigger:
-    - main
+    - main-vs-deps
 
 parameters:
   - name: prNumber
@@ -122,4 +122,4 @@ stages:
               gitHubConnection: 'dotnet-comment-bot-service-connection'
               repositoryName: '$(Build.Repository.Name)'
               id: ${{ parameters.prNumber }}
-              comment: 'DartLab pipeline [run]($(System.TeamFoundationCollectionUri)$(System.TeamProject)/_build/results?buildId=$(Build.BuildId)) did not complete successfully for ${{ parameters.sha }}'
+              comment: 'DartLab pipeline [run]($(System.TeamFoundationCollectionUri)$(System.TeamProject)/_build/results?buildId=$(Build.BuildId)) did not complete successfully for ${{ parameters.sha }}'
@@ -68,7 +68,7 @@ parameters:
 - name: queueName
   displayName: Queue Name
   type: string
-  default: windows.vs2022preview.amd64.open
+  default: windows.vs2022preview.scout.amd64.open
   values:
   - windows.vs2022.amd64.open
   - windows.vs2022.scout.amd64.open

@@ -400,13 +400,19 @@ stages:
           configuration: Release
       - name: compilerChange
         value: $[dependencies.Determine_Changes.outputs['SetPathVars_compilers.containsChange']]
+      # Set NUGET_PACKAGES to fix issues with package Restore when building with `-ci`.
+      # Workaround for https://github.com/dotnet/arcade/issues/15970
+      - name: NUGET_PACKAGES
+        value: $(Build.SourcesDirectory)\.packages
     steps:
       - template: eng/pipelines/checkout-windows-task.yml
 
       - powershell: eng/build.ps1 -configuration Release -prepareMachine -ci -restore -binaryLogName Restore.binlog 
         displayName: Restore
 
-      - powershell: eng/build.ps1 -configuration Release -prepareMachine -ci -build -pack -publish -sign -binaryLogName Build.binlog /p:DotnetPublishUsingPipelines=true /p:ContinuousIntegrationBuildCorrectness=true
+      # We additionally restore during the build because the Microsoft.DotNet.Build.Tasks.Feed package only restores when we pass `-publish`. See https://github.com/dotnet/arcade/blob/37ccfd66358af6a37a0ec385ec31d1d71bdd8723/src/Microsoft.DotNet.Arcade.Sdk/tools/Tools.proj#L61-L66
+      # Passing `-publish` during the restore step above fails due to no items needing published.
+      - powershell: eng/build.ps1 -configuration Release -prepareMachine -ci -restore -build -pack -publish -sign -binaryLogName Build.binlog /p:DotnetPublishUsingPipelines=true /p:ContinuousIntegrationBuildCorrectness=true
         displayName: Build
 
       # While this task is not executed in the official build, this serves as a PR check for whether symbol exclusions

diff --git a/docs/contributing/Building, Debugging, and Testing on Unix.md b/docs/contributing/Building, Debugging, and Testing on Unix.md
@@ -12,7 +12,7 @@ Particularly for developers who aren't experienced with .NET Core development on
 1. Install [VS Code](https://code.visualstudio.com/Download)
     - After you install VS Code, install the [C# extension](https://marketplace.visualstudio.com/items?itemName=ms-dotnettools.csharp)
     - Important tip: You can look up editor commands by name by hitting *Ctrl+Shift+P*, or by hitting *Ctrl+P* and typing a `>` character. This will help you get familiar with editor commands mentioned below. On a Mac, use *⌘* instead of *Ctrl*.
-1. Install the [.NET 9.0 SDK](https://dotnet.microsoft.com/en-us/download/dotnet/9.0) which matches the `sdk.version` property in [global.json](../../global.json#L3)
+1. Install the [.NET 10.0 SDK](https://dotnet.microsoft.com/en-us/download/dotnet/10.0) which matches the `sdk.version` property in [global.json](../../global.json#L3)
 3. You can build from VS Code by running the *Run Build Task* command, then selecting an appropriate task such as *build* or *build current project* (the latter builds the containing project for the current file you're viewing in the editor).
 4. You can run tests from VS Code by opening a test class in the editor, then using the *Run Tests in Context* and *Debug Tests in Context* editor commands. You may want to bind these commands to keyboard shortcuts that match their Visual Studio equivalents (**Ctrl+R, T** for *Run Tests in Context* and **Ctrl+R, Ctrl+T** for *Debug Tests in Context*).
 5. You can launch a new VS Code instance with the language server from your current code by running the "launch vscode with language server" task.

diff --git a/docs/contributing/Building, Debugging, and Testing on Windows.md b/docs/contributing/Building, Debugging, and Testing on Windows.md
@@ -20,7 +20,7 @@ The minimal required version of .NET Framework is 4.7.2.
     - Ensure C# and Visual Basic, MSBuild, and .NET Core are included in the selected individual components
     - Ensure "Use previews of the .NET Core SDK" is checked in Tools -> Options -> Environment -> Preview Features
     - Restart Visual Studio
-1. Install the [.NET 9.0 SDK](https://dotnet.microsoft.com/en-us/download/dotnet/9.0) which matches the `sdk.version` property in [global.json](../../global.json#L3)
+1. Install the [.NET 10.0 SDK](https://dotnet.microsoft.com/en-us/download/dotnet/10.0) which matches the `sdk.version` property in [global.json](../../global.json#L3)
 1. [PowerShell 5.0 or newer](https://docs.microsoft.com/en-us/powershell/scripting/setup/installing-windows-powershell). If you are on Windows 10, you are fine; you'll only need to upgrade if you're on earlier versions of Windows. The download link is under the ["Upgrading existing Windows PowerShell"](https://docs.microsoft.com/en-us/powershell/scripting/install/installing-windows-powershell?view=powershell-6#upgrading-existing-windows-powershell) heading.
 1. Run Restore.cmd
 1. Open Roslyn.sln

diff --git a/docs/contributing/Compiler Test Plan.md b/docs/contributing/Compiler Test Plan.md
@@ -55,7 +55,7 @@ This document provides guidance for thinking about language interactions and tes
   - Compiler-recognized attributes should not have any effect in earlier LangVersions,
     except a LangVersion error should be reported when functionality depending on the attribute is used
     (for example, InlineArray conversion to Span).
-- Generics (type arguments, variance, constraints including `class`, `struct`, `new()`, `unmanaged`, `notnull`, types and interfaces with nullability)
+- Generics (type arguments, variance, constraints including `class`, `struct`, `new()`, `unmanaged`, `notnull`, `allows ref struct`, types and interfaces with nullability)
 - Default and constant values
 - Partial classes
 - Literals
@@ -80,7 +80,7 @@ This document provides guidance for thinking about language interactions and tes
 - Readonly members on structs (methods, property/indexer accessors, custom event accessors)
 - SkipLocalsInit
 - Method override or explicit implementation with `where T : { class, struct, default }`
-- `extension` blocks
+- `extension` blocks (emitted with content-based names)
 
 # Code
 - Operators (see Eric's list below)

diff --git a/docs/features/incremental-generators.cookbook.md b/docs/features/incremental-generators.cookbook.md
@@ -21,6 +21,8 @@ of scope in the final design of the shipping feature.
     - [Pipeline model design](#pipeline-model-design)
     - [Use `ForAttributeWithMetadataName`](#use-forattributewithmetadataname)
     - [Use an indented text writer, not `SyntaxNode`s, for generation](#use-an-indented-text-writer-not-syntaxnodes-for-generation)
+    - [Put `Microsoft.CodeAnalysis.EmbeddedAttribute` on generated marker types](#put-microsoftcodeanalysisembeddedattribute-on-generated-marker-types)
+    - [Do not scan for types that indirectly implement interfaces, indirectly inherit from types, or are indirectly marked by an attribute from an interface or base type](#do-not-scan-for-types-that-indirectly-implement-interfaces-indirectly-inherit-from-types-or-are-indirectly-marked-by-an-attribute-from-an-interface-or-base-type)
   - [Designs](#designs)
     - [Generated class](#generated-class)
     - [Additional file transformation](#additional-file-transformation)
@@ -135,6 +137,27 @@ project, it will not include that type in lookup results. To ensure that `Micros
 Another option is to provide an assembly in your nuget package that defines your marker attributes, but this can be more difficult to author. We recommend the
 `EmbeddedAttribute` approach, unless you need to support versions of Roslyn lower than 4.14.
 
+### Do not scan for types that indirectly implement interfaces, indirectly inherit from types, or are indirectly marked by an attribute from an interface or base type
+
+Using an interface/base type marker can be a very tempting and natural fit for generators. However, scanning for these types of markers is _very_ expensive, and cannot
+be done incrementally. Doing so can have an outsized impact on IDE and command-line performance, even for fairly small consuming users. These scenarios are:
+
+* A user implements an interface on `BaseModelType`, and then the generator looks all derived types from `BaseModelType`. Because the generator cannot know ahead of time
+  what `BaseModelType` actually is, it means that the generator has to fetch `AllInterfaces` on every single type in the compilation so it can scan for the marker
+  interface. This will end up occurring either on every keystroke or every file save, depending on what mode the user is running generators in; either one is disastrous
+  for IDE performance, even when trying to optimize by scoping down the scanning to only types with a base list.
+* A user inherits from a generator-defined `BaseSerializerType`, and the generator looks for anything that inherits from that type, either directly or indirectly. Similar
+  to the above scenario, the generator will need to scan all types with a base type in the entire compilation for the inherited `BaseSerializerType`, which will heavily
+  impact IDE performance.
+* A generator looks among all base types/implemented interfaces for a type that is attributed with a generator's marker attribute. This is effectively either scenario 1
+  or 2, just with a different search criteria.
+* A generator leaves its marker attribute unsealed, and expects users to be able to derive their own attributes from that marker, as a source of parameter customization.
+  This has a couple of problems: first, every attributed type needs to be checked to see if the attribute inherits from the marker attribute. While not as performance
+  impacting as the first three scenarios, this isn't great for performance. Second, and more importantly, there is no good way to retrieve any customizations from the
+  inherited attribute. These attributes are not instantiated by the source generator, so any parameters passed to the `base()` constructor call or values that are assigned
+  to any properties of the base attribute are not visible to the generator. Prefer using FAWMN-driven development here, and using an analyzer to inform the user if they
+  need to inherit from some base class for your generator to work correctly.
+
 ## Designs
 
 This section is broken down by user scenarios, with general solutions listed first, and more specific examples later on.

@@ -4,7 +4,7 @@
     <RoslynDiagnosticsNugetPackageVersion>3.11.0-beta1.24081.1</RoslynDiagnosticsNugetPackageVersion>
     <MicrosoftCodeAnalysisNetAnalyzersVersion>8.0.0-preview.23468.1</MicrosoftCodeAnalysisNetAnalyzersVersion>
     <MicrosoftCodeAnalysisTestingVersion>1.1.3-beta1.24319.1</MicrosoftCodeAnalysisTestingVersion>
-    <MicrosoftVisualStudioExtensibilityTestingVersion>0.1.785-beta</MicrosoftVisualStudioExtensibilityTestingVersion>
+    <MicrosoftVisualStudioExtensibilityTestingVersion>0.1.796-beta</MicrosoftVisualStudioExtensibilityTestingVersion>
     <_BasicReferenceAssembliesVersion>1.7.9</_BasicReferenceAssembliesVersion>
     <!-- CodeStyleAnalyzerVersion should we updated together with version of dotnet-format in dotnet-tools.json -->
     <CodeStyleAnalyzerVersion>4.8.0-3.final</CodeStyleAnalyzerVersion>
@@ -199,7 +199,7 @@
     <PackageVersion Include="System.Runtime.CompilerServices.Unsafe" Version="$(SystemRuntimeCompilerServicesUnsafeVersion)" />
     <PackageVersion Include="System.Security.Cryptography.ProtectedData" Version="$(SystemSecurityCryptographyProtectedDataVersion)" />
     <PackageVersion Include="System.Security.Permissions" Version="$(SystemSecurityPermissionsVersion)" />
-    <PackageVersion Include="System.Text.Encoding.CodePages" Version="7.0.0" />
+    <PackageVersion Include="System.Text.Encoding.CodePages" Version="8.0.0" />
     <PackageVersion Include="System.Threading.Tasks.Dataflow" Version="$(SystemThreadingTasksDataflowVersion)" />
     <PackageVersion Include="System.Threading.Tasks.Extensions" Version="$(SystemThreadingTasksExtensionsVersion)" />
     <PackageVersion Include="System.ValueTuple" Version="$(SystemValueTupleVersion)" />
@@ -215,7 +215,7 @@
     <PackageVersion Include="System.Text.Encodings.Web" Version="$(SystemTextEncodingsWebVersion)" />
     <!-- Note: When updating SystemTextJsonVersion ensure that the version is no higher than what is used by MSBuild. -->
     <PackageVersion Include="System.Text.Json" Version="$(SystemTextJsonVersion)" />
-    <PackageVersion Include="System.Threading.Channels" Version="7.0.0" />
+    <PackageVersion Include="System.Threading.Channels" Version="8.0.0" />
 
     <PackageVersion Include="Microsoft.IO.Redist" Version="$(MicrosoftIORedistVersion)" />
 
@@ -273,7 +273,7 @@
     <PackageVersion Include="xunit.core" Version="$(_xunitVersion)" />
     <PackageVersion Include="Xunit.Combinatorial" Version="1.6.24" />
     <PackageVersion Include="xunit.extensibility.core" Version="$(_xunitVersion)" />
-    <PackageVersion Include="xunit.runner.visualstudio" Version="2.4.5 " />
+    <PackageVersion Include="xunit.runner.visualstudio" Version="3.1.3" />
     <PackageVersion Include="xunit.runner.utility" Version="$(_xunitVersion)" />
     <PackageVersion Include="xunit.abstractions" Version="2.0.3" />
     <PackageVersion Include="xunit.extensibility.execution" Version="$(_xunitVersion)" />
@@ -319,16 +319,16 @@
       but not higher than our minimum dogfoodable Visual Studio version, or else
       the generators we build would load on the command line but not load in IDEs.
     -->
-    <PackageVersion Include="Microsoft.CodeAnalysis.Common" Version="4.1.0" />
+    <PackageVersion Include="Microsoft.CodeAnalysis.Common" Version="4.12.0" />
     <!--
       The version of Roslyn used in the RoslynAnalyzers varies. These are defaults that
       will be overridden in the RoslynAnalyzer project files.
     -->
-    <!--<PackageVersion Include="Microsoft.CodeAnalysis" Version="4.1.0" /> -->
-    <PackageVersion Include="Microsoft.CodeAnalysis.CSharp" Version="4.1.0" />
-    <PackageVersion Include="Microsoft.CodeAnalysis.CSharp.Workspaces" Version="4.1.0" />
-    <PackageVersion Include="Microsoft.CodeAnalysis.VisualBasic" Version="4.1.0" />
-    <PackageVersion Include="Microsoft.CodeAnalysis.VisualBasic.Workspaces" Version="4.1.0" />
-    <PackageVersion Include="Microsoft.CodeAnalysis.Workspaces.Common" Version="4.1.0" />
+    <!--<PackageVersion Include="Microsoft.CodeAnalysis" Version="4.12.0" /> -->
+    <PackageVersion Include="Microsoft.CodeAnalysis.CSharp" Version="4.12.0" />
+    <PackageVersion Include="Microsoft.CodeAnalysis.CSharp.Workspaces" Version="4.12.0" />
+    <PackageVersion Include="Microsoft.CodeAnalysis.VisualBasic" Version="4.12.0" />
+    <PackageVersion Include="Microsoft.CodeAnalysis.VisualBasic.Workspaces" Version="4.12.0" />
+    <PackageVersion Include="Microsoft.CodeAnalysis.Workspaces.Common" Version="4.12.0" />
  </ItemGroup>
 </Project>
@@ -5,8 +5,9 @@
   </PropertyGroup>
 
   <!-- Update Artifacts with Kind=Package to have additional metadata item Category="ToolingPackage".
-       Depending on channel configuration, this means that these assets could be pushed to a different feed. -->
-  <ItemGroup>
+       Depending on channel configuration, this means that these assets could be pushed to a different feed.
+       Do not include these for source-only builds since these files aren't intended to be published in that mode. -->
+  <ItemGroup Condition="'$(DotNetBuildSourceOnly)' != 'true'">
     <Artifact Update="@(Artifact->WithMetadataValue('Kind', 'Package'))" Category="ToolingPackage" />
 
     <FilesToPublishToSymbolServer Include="$(ArtifactsBinDir)**/Microsoft.Build.Tasks.CodeAnalysis.pdb" />