Microsoft.Interop.SourceGeneration gets built twice (with a potential of a race)

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#111,654 opened on Jan 21, 2025 2 comments 0 reactions 0 assignees View on GitHub

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Assessment

Difficulty: 4/5
Estimated time: 3-5 days
Newbie friendliness: 35/100

Issue type: Bug
Clarity: Needs clarification
Activity status: Quiet
Tech stack: csharp
Domain: build-system

Research direction

Start by examining the build output for Microsoft.Interop.SourceGeneration and DownlevelLibraryImportGenerator, then trace the build entry points that schedule those projects. Compare the repeated Microsoft.Interop.SourceGeneration and DownlevelLibraryImportGenerator entries and determine whether duplicate scheduling can race. Done means each project is built only once in the relevant build sequence.

Written by the indexing model from the issue text.

Description

area-System.Runtime.InteropServices source-generator tenet-build-performance

  installer.tasks -> C:\git\runtime4\artifacts\bin\installer.tasks\Debug\net10.0\installer.tasks.dll
  Crossgen2Tasks -> C:\git\runtime4\artifacts\bin\Crossgen2Tasks\Debug\net10.0\Crossgen2Tasks.dll
  Microsoft.Interop.SourceGeneration -> C:\git\runtime4\artifacts\bin\Microsoft.Interop.SourceGeneration\Debug\netstandard2.0\Microsoft.Interop.SourceGeneration.dll
  DownlevelLibraryImportGenerator -> C:\git\runtime4\artifacts\bin\DownlevelLibraryImportGenerator\Debug\netstandard2.0\Microsoft.Interop.LibraryImportGenerator.Downle
  vel.dll
  installer.tasks -> C:\git\runtime4\artifacts\bin\installer.tasks\Debug\net472\installer.tasks.dll
  ILLink.RoslynAnalyzer -> C:\git\runtime4\artifacts\bin\ILLink.RoslynAnalyzer\Debug\netstandard2.0\ILLink.RoslynAnalyzer.dll
  ILLink.CodeFixProvider -> C:\git\runtime4\artifacts\bin\ILLink.CodeFixProvider\Debug\netstandard2.0\ILLink.CodeFixProvider.dll
  Mono.Linker -> C:\git\runtime4\artifacts\bin\Mono.Linker\ref\Debug\net10.0\illink.dll
  Mono.Linker -> C:\git\runtime4\artifacts\bin\Mono.Linker\Debug\net10.0\illink.dll
  ILLink.Tasks -> C:\git\runtime4\artifacts\bin\ILLink.Tasks\Debug\net\ILLink.Tasks.dll
  System.Private.CoreLib.Generators -> C:\git\runtime4\artifacts\bin\System.Private.CoreLib.Generators\Debug\netstandard2.0\System.Private.CoreLib.Generators.dll
  System.Private.CoreLib -> C:\git\runtime4\artifacts\bin\System.Private.CoreLib\ref\Debug\net10.0\System.Private.CoreLib.dll
  Microsoft.Interop.SourceGeneration -> C:\git\runtime4\artifacts\bin\Microsoft.Interop.SourceGeneration\Debug\netstandard2.0\Microsoft.Interop.SourceGeneration.dll
  LibraryImportGenerator -> C:\git\runtime4\artifacts\bin\LibraryImportGenerator\Debug\netstandard2.0\Microsoft.Interop.LibraryImportGenerator.dll

and the build then later yet again builds the DownlevelLibraryImportGenerator project:

  BUILD: Product binaries are available at C:\git\runtime4\artifacts\bin\coreclr\linux.x64.Debug\x64
  runincontext -> C:\git\runtime4\artifacts\bin\coreclr\windows.x64.Debug\runincontext.dll
  tieringtest -> C:\git\runtime4\artifacts\bin\coreclr\windows.x64.Debug\tieringtest.dll
  DownlevelLibraryImportGenerator -> C:\git\runtime4\artifacts\bin\DownlevelLibraryImportGenerator\Debug\netstandard2.0\Microsoft.Interop.LibraryImportGenerator.Downle
  vel.dll
  ILCompiler.TypeSystem -> C:\git\runtime4\artifacts\bin\ILCompiler.TypeSystem\x64\Debug\ILCompiler.TypeSystem.dll

cc @jkoritzinsky

Dominant language: C#
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