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Remove base DAM mismatch warning on types - #119419

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Merged

Remove base DAM mismatch warning on types#119419
sbomer merged 15 commits into
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sbomer:removeBaseDAMWarning

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Fixes#118713(analyzer only for now)
Fixes#119290

This removes the warning for DAM annotation mismatch in the base types of a type declaration. This doesn't cause holes because we produce warnings on the construction of the derived type. Removing the warning enables the use of static methods on such a type.

While implementing this I ran into an ILLink bug around branch removal. We weren't fixing up IL offsets during branch removal, but we were using the offsets as a dictionary key when tracking known stacks during method body scanning. This includes a change to fix up IL offsets during the IL rewrite when we remove unreachable blocks.

Depends on #119291

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@sbomer
Add back interface warning
c54b8af
Moving this warning is more complicated than that for base types
because we would either need to warn on conversion to interfaces,
or warn on every constructor (for kept interface implementations).
@sbomer
Remove base warning for ILLink
a2a7bcb
@sbomersbomer changed the title Remove analyzer DAM warning on typesRemove base DAM mismatch warning on typesSep 8, 2025
@sbomer
Same for ILC
1bdcc9d
@sbomer
Fix ILLink generic behavior
ccd41ff
- Move new constraint processing to generic dataflow
- Take new constraint into account for requires dataflow check
@sbomer
PR feedback
e74bcea
@sbomer
Merge branch 'newConstraintHole' into removeBaseDAMWarning
c465af2
@sbomer
Add test to analyzer tests
73621ee
@sbomer
Fix offsets when rewriting IL
b2ad90e
MethodBodyScanner tracks known stacks by IL offset,
so these need to be correct when analyzing IL. We can't just
wait for cecil to update offsets for us when writing to disk.
@build-analysisbuild-analysisBot mentioned this pull request Sep 13, 2025
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sbomer requested a review from a teamSeptember 15, 2025 20:08
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Pull Request Overview

This pull request fixes issues related to Dynamically Accessed Members (DAM) annotation mismatch warnings on base types of type declarations. The changes remove these warnings for base type mismatches since warnings are already produced at construction of derived types. This enables the use of static methods on such types. Additionally, it includes a fix for an ILLink bug around branch removal that affects IL offset tracking during method body scanning.

Key changes include:

  • Removal of DAM mismatch warnings for base types in type declarations
  • Fix for IL offset handling during unreachable block optimization
  • Updates to test expectations reflecting the warning removal
  • Refactoring of analyzer context to better handle trim analyzer instances

Reviewed Changes

Copilot reviewed 27 out of 28 changed files in this pull request and generated 5 comments.

Show a summary per file
FileDescription
src/tools/illink/test/Mono.Linker.Tests/TestCasesRunner/ResultChecker.csComments out debug logging for test message matching
src/tools/illink/test/Mono.Linker.Tests.Cases/RequiresCapability/RequiresOnClass.csRemoves expected warnings for base type DAM mismatches
src/tools/illink/test/Mono.Linker.Tests.Cases/Generics/GenericConstraints.csAdds test case for new constraint on methods
src/tools/illink/test/Mono.Linker.Tests.Cases/DataFlow/GenericParameterWarningLocation.csUpdates warning expectations and adds constructor calls
src/tools/illink/test/Mono.Linker.Tests.Cases/DataFlow/GenericParameterDataFlowMarking.csUpdates test expectations and changes class to interface
src/tools/illink/test/Mono.Linker.Tests.Cases/DataFlow/GenericParameterDataFlow.csRemoves base type DAM mismatch warnings from tests
src/tools/illink/test/ILLink.RoslynAnalyzer.Tests/GenericsTests.csAdds test method for generic constraints
src/tools/illink/src/linker/Linker.Steps/UnreachableBlocksOptimizer.csFixes IL offset tracking during instruction replacement
src/tools/illink/src/linker/Linker.Steps/MarkStep.csRemoves base type generic argument data flow processing
src/tools/illink/src/linker/Linker.Dataflow/GenericArgumentDataFlow.csAdds new constraint handling and updates parameter processing
src/tools/illink/src/linker/Linker.Dataflow/FlowAnnotations.csAdds methods to check for generic parameter new constraints
src/tools/illink/src/ILLink.RoslynAnalyzer/TrimAnalysis/TrimAnalysisVisitor.csUpdates analyzer context usage
src/tools/illink/src/ILLink.RoslynAnalyzer/TrimAnalysis/TrimAnalysisReflectionAccessPattern.csUpdates trim analyzer reference
src/tools/illink/src/ILLink.RoslynAnalyzer/TrimAnalysis/TrimAnalysisMethodCallPattern.csUpdates trim analyzer reference
src/tools/illink/src/ILLink.RoslynAnalyzer/TrimAnalysis/TrimAnalysisGenericInstantiationPattern.csUpdates analyzer iteration
src/tools/illink/src/ILLink.RoslynAnalyzer/TrimAnalysis/TrimAnalysisAssignmentPattern.csUpdates trim analyzer reference
src/tools/illink/src/ILLink.RoslynAnalyzer/TrimAnalysis/RequireDynamicallyAccessedMembersAction.csUpdates constructor to use specific analyzer
src/tools/illink/src/ILLink.RoslynAnalyzer/TrimAnalysis/HandleCallAction.csUpdates constructor parameter
src/tools/illink/src/ILLink.RoslynAnalyzer/TrimAnalysis/GenericArgumentDataFlow.csRefactors to use specific analyzer instances
src/tools/illink/src/ILLink.RoslynAnalyzer/TrimAnalysis/FeatureCheckReturnValuePattern.csUpdates trim analyzer reference
src/tools/illink/src/ILLink.RoslynAnalyzer/RequiresUnreferencedCodeAnalyzer.csAdds generic instantiation processing
src/tools/illink/src/ILLink.RoslynAnalyzer/RequiresAnalyzerBase.csAdds generic instantiation processing base functionality
src/tools/illink/src/ILLink.RoslynAnalyzer/DynamicallyAccessedMembersAnalyzer.csRemoves base type processing
src/tools/illink/src/ILLink.RoslynAnalyzer/DataFlowAnalyzerContext.csChanges from boolean flag to specific analyzer instance
src/coreclr/tools/aot/ILCompiler.Trimming.Tests/TestCasesRunner/ResultChecker.csComments out debug logging for test message matching
src/coreclr/tools/aot/ILCompiler.Compiler/Compiler/DependencyAnalysis/DataflowAnalyzedTypeDefinitionNode.csRemoves base type generic argument data flow processing
src/coreclr/tools/aot/ILCompiler.Compiler/Compiler/Dataflow/GenericArgumentDataFlow.csAdds comments about new constraint handling

Comment threadsrc/tools/illink/src/linker/Linker.Steps/UnreachableBlocksOptimizer.cs
Comment threadsrc/tools/illink/src/linker/Linker.Steps/UnreachableBlocksOptimizer.cs
Comment threadsrc/tools/illink/src/linker/Linker.Steps/UnreachableBlocksOptimizer.cs
Comment threadsrc/tools/illink/src/linker/Linker.Steps/UnreachableBlocksOptimizer.cs
Comment threadsrc/tools/illink/src/linker/Linker.Steps/UnreachableBlocksOptimizer.cs
jtschuster
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It feels a bit awkward to be passing around the instances of the analyzers, but I don't have a better solution.

Comment threadsrc/tools/illink/test/Mono.Linker.Tests.Cases/DataFlow/GenericParameterDataFlow.cs Outdated
Comment threadsrc/tools/illink/test/Mono.Linker.Tests.Cases/Generics/GenericConstraints.cs
Comment threadsrc/tools/illink/test/Mono.Linker.Tests.Cases/DataFlow/GenericParameterWarningLocation.cs Outdated
Comment threadsrc/tools/illink/src/ILLink.RoslynAnalyzer/TrimAnalysis/GenericArgumentDataFlow.cs Outdated
@sbomer
PR feedback
3f36272
- Use interface for generic dataflow
- Remove outdated comment
- Clarify expected warning reason
- Add Kept attributes for clarity
@sbomer
sbomer enabled auto-merge (squash) September 16, 2025 21:19
@jtschuster
jtschuster disabled auto-merge January 9, 2026 21:58
@sbomer
sbomer merged commit a2a8bc0 into dotnet:mainApr 14, 2026
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@jtschusterjtschusterjtschuster approved these changes
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ILLink: extra warning for generic parameter with new constraint and annotation Remove DAM warning for base types/interfaces

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Remove base DAM mismatch warning on types by sbomer · Pull Request #119419 · dotnet/runtime · GitHub
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Remove base DAM mismatch warning on types - #119419
Merged
sbomer merged 15 commits into
dotnet:mainfrom 
sbomer:removeBaseDAMWarning
Apr 14, 2026
Merged
Remove base DAM mismatch warning on types#119419
sbomer merged 15 commits into
dotnet:mainfrom 
sbomer:removeBaseDAMWarning
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Fixes#118713(analyzer only for now)
Fixes#119290
This removes the warning for DAM annotation mismatch in the base types of a type declaration. This doesn't cause holes because we produce warnings on the construction of the derived type. Removing the warning enables the use of static methods on such a type.
While implementing this I ran into an ILLink bug around branch removal. We weren't fixing up IL offsets during branch removal, but we were using the offsets as a dictionary key when tracking known stacks during method body scanning. This includes a change to fix up IL offsets during the IL rewrite when we remove unreachable blocks.
Depends on #119291
@github-actionsgithub-actionsBot
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Issues associated with delivering a linker friendly framework
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@sbomer
Add back interface warning
c54b8af
Moving this warning is more complicated than that for base types
because we would either need to warn on conversion to interfaces,
or warn on every constructor (for kept interface implementations).
@sbomer
Remove base warning for ILLink
a2a7bcb
@sbomersbomer
changed the title
Remove analyzer DAM warning on typesRemove base DAM mismatch warning on typesSep 8, 2025
@sbomer
Same for ILC
1bdcc9d
@sbomer
Fix ILLink generic behavior
ccd41ff
- Move new constraint processing to generic dataflow
- Take new constraint into account for requires dataflow check
@sbomer
PR feedback
e74bcea
@sbomer
Merge branch 'newConstraintHole' into removeBaseDAMWarning
c465af2
@sbomer
Add test to analyzer tests
73621ee
@sbomer
Fix offsets when rewriting IL
b2ad90e
MethodBodyScanner tracks known stacks by IL offset,
so these need to be correct when analyzing IL. We can't just
wait for cecil to update offsets for us when writing to disk.
@build-analysisbuild-analysisBot
mentioned this pull request
Sep 13, 2025

Open

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September 15, 2025 20:08
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Pull Request Overview
This pull request fixes issues related to Dynamically Accessed Members (DAM) annotation mismatch warnings on base types of type declarations. The changes remove these warnings for base type mismatches since warnings are already produced at construction of derived types. This enables the use of static methods on such types. Additionally, it includes a fix for an ILLink bug around branch removal that affects IL offset tracking during method body scanning.
Key changes include:
  • Removal of DAM mismatch warnings for base types in type declarations
  • Fix for IL offset handling during unreachable block optimization
  • Updates to test expectations reflecting the warning removal
  • Refactoring of analyzer context to better handle trim analyzer instances
Reviewed Changes
Copilot reviewed 27 out of 28 changed files in this pull request and generated 5 comments.
Show a summary per file
FileDescription
src/tools/illink/test/Mono.Linker.Tests/TestCasesRunner/ResultChecker.csComments out debug logging for test message matching
src/tools/illink/test/Mono.Linker.Tests.Cases/RequiresCapability/RequiresOnClass.csRemoves expected warnings for base type DAM mismatches
src/tools/illink/test/Mono.Linker.Tests.Cases/Generics/GenericConstraints.csAdds test case for new constraint on methods
src/tools/illink/test/Mono.Linker.Tests.Cases/DataFlow/GenericParameterWarningLocation.csUpdates warning expectations and adds constructor calls
src/tools/illink/test/Mono.Linker.Tests.Cases/DataFlow/GenericParameterDataFlowMarking.csUpdates test expectations and changes class to interface
src/tools/illink/test/Mono.Linker.Tests.Cases/DataFlow/GenericParameterDataFlow.csRemoves base type DAM mismatch warnings from tests
src/tools/illink/test/ILLink.RoslynAnalyzer.Tests/GenericsTests.csAdds test method for generic constraints
src/tools/illink/src/linker/Linker.Steps/UnreachableBlocksOptimizer.csFixes IL offset tracking during instruction replacement
src/tools/illink/src/linker/Linker.Steps/MarkStep.csRemoves base type generic argument data flow processing
src/tools/illink/src/linker/Linker.Dataflow/GenericArgumentDataFlow.csAdds new constraint handling and updates parameter processing
src/tools/illink/src/linker/Linker.Dataflow/FlowAnnotations.csAdds methods to check for generic parameter new constraints
src/tools/illink/src/ILLink.RoslynAnalyzer/TrimAnalysis/TrimAnalysisVisitor.csUpdates analyzer context usage
src/tools/illink/src/ILLink.RoslynAnalyzer/TrimAnalysis/TrimAnalysisReflectionAccessPattern.csUpdates trim analyzer reference
src/tools/illink/src/ILLink.RoslynAnalyzer/TrimAnalysis/TrimAnalysisMethodCallPattern.csUpdates trim analyzer reference
src/tools/illink/src/ILLink.RoslynAnalyzer/TrimAnalysis/TrimAnalysisGenericInstantiationPattern.csUpdates analyzer iteration
src/tools/illink/src/ILLink.RoslynAnalyzer/TrimAnalysis/TrimAnalysisAssignmentPattern.csUpdates trim analyzer reference
src/tools/illink/src/ILLink.RoslynAnalyzer/TrimAnalysis/RequireDynamicallyAccessedMembersAction.csUpdates constructor to use specific analyzer
src/tools/illink/src/ILLink.RoslynAnalyzer/TrimAnalysis/HandleCallAction.csUpdates constructor parameter
src/tools/illink/src/ILLink.RoslynAnalyzer/TrimAnalysis/GenericArgumentDataFlow.csRefactors to use specific analyzer instances
src/tools/illink/src/ILLink.RoslynAnalyzer/TrimAnalysis/FeatureCheckReturnValuePattern.csUpdates trim analyzer reference
src/tools/illink/src/ILLink.RoslynAnalyzer/RequiresUnreferencedCodeAnalyzer.csAdds generic instantiation processing
src/tools/illink/src/ILLink.RoslynAnalyzer/RequiresAnalyzerBase.csAdds generic instantiation processing base functionality
src/tools/illink/src/ILLink.RoslynAnalyzer/DynamicallyAccessedMembersAnalyzer.csRemoves base type processing
src/tools/illink/src/ILLink.RoslynAnalyzer/DataFlowAnalyzerContext.csChanges from boolean flag to specific analyzer instance
src/coreclr/tools/aot/ILCompiler.Trimming.Tests/TestCasesRunner/ResultChecker.csComments out debug logging for test message matching
src/coreclr/tools/aot/ILCompiler.Compiler/Compiler/DependencyAnalysis/DataflowAnalyzedTypeDefinitionNode.csRemoves base type generic argument data flow processing
src/coreclr/tools/aot/ILCompiler.Compiler/Compiler/Dataflow/GenericArgumentDataFlow.csAdds comments about new constraint handling
Comment threadsrc/tools/illink/src/linker/Linker.Steps/UnreachableBlocksOptimizer.cs
Comment threadsrc/tools/illink/src/linker/Linker.Steps/UnreachableBlocksOptimizer.cs
Comment threadsrc/tools/illink/src/linker/Linker.Steps/UnreachableBlocksOptimizer.cs
Comment threadsrc/tools/illink/src/linker/Linker.Steps/UnreachableBlocksOptimizer.cs
Comment threadsrc/tools/illink/src/linker/Linker.Steps/UnreachableBlocksOptimizer.cs
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It feels a bit awkward to be passing around the instances of the analyzers, but I don't have a better solution.
Comment threadsrc/tools/illink/test/Mono.Linker.Tests.Cases/DataFlow/GenericParameterDataFlow.cs
Outdated

Comment threadsrc/tools/illink/test/Mono.Linker.Tests.Cases/Generics/GenericConstraints.cs
Comment threadsrc/tools/illink/test/Mono.Linker.Tests.Cases/DataFlow/GenericParameterWarningLocation.cs
Outdated

Comment threadsrc/tools/illink/src/ILLink.RoslynAnalyzer/TrimAnalysis/GenericArgumentDataFlow.cs
Outdated

@sbomer
PR feedback
3f36272
- Use interface for generic dataflow
- Remove outdated comment
- Clarify expected warning reason
- Add Kept attributes for clarity
@sbomer
sbomer
enabled auto-merge (squash)
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@jtschuster
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@sbomer
sbomer
merged commit a2a8bc0
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@jtschusterjtschusterjtschuster approved these changes
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ILLink: extra warning for generic parameter with new constraint and annotation

Remove DAM warning for base types/interfaces


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Remove base DAM mismatch warning on types by sbomer · Pull Request #119419 · dotnet/runtime · GitHub
Skip to content
Remove base DAM mismatch warning on types - #119419
Merged
sbomer merged 15 commits into
dotnet:mainfrom 
sbomer:removeBaseDAMWarning
Apr 14, 2026
Merged
Remove base DAM mismatch warning on types#119419
sbomer merged 15 commits into
dotnet:mainfrom 
sbomer:removeBaseDAMWarning
Conversation
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commented
Sep 6, 2025•

edited

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Fixes#118713(analyzer only for now)
Fixes#119290
This removes the warning for DAM annotation mismatch in the base types of a type declaration. This doesn't cause holes because we produce warnings on the construction of the derived type. Removing the warning enables the use of static methods on such a type.
While implementing this I ran into an ILLink bug around branch removal. We weren't fixing up IL offsets during branch removal, but we were using the offsets as a dictionary key when tracking known stacks during method body scanning. This includes a change to fix up IL offsets during the IL rewrite when we remove unreachable blocks.
Depends on #119291
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area-Tools-ILLink
.NET linker development as well as trimming analyzers
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linkable-framework
Issues associated with delivering a linker friendly framework
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Tagging subscribers to this area: @dotnet/illink

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@sbomer
Add back interface warning
c54b8af
Moving this warning is more complicated than that for base types
because we would either need to warn on conversion to interfaces,
or warn on every constructor (for kept interface implementations).
@sbomer
Remove base warning for ILLink
a2a7bcb
@sbomersbomer
changed the title
Remove analyzer DAM warning on typesRemove base DAM mismatch warning on typesSep 8, 2025
@sbomer
Same for ILC
1bdcc9d
@sbomer
Fix ILLink generic behavior
ccd41ff
- Move new constraint processing to generic dataflow
- Take new constraint into account for requires dataflow check
@sbomer
PR feedback
e74bcea
@sbomer
Merge branch 'newConstraintHole' into removeBaseDAMWarning
c465af2
@sbomer
Add test to analyzer tests
73621ee
@sbomer
Fix offsets when rewriting IL
b2ad90e
MethodBodyScanner tracks known stacks by IL offset,
so these need to be correct when analyzing IL. We can't just
wait for cecil to update offsets for us when writing to disk.
@build-analysisbuild-analysisBot
mentioned this pull request
Sep 13, 2025

Open

3 tasks
@sbomer
sbomer
requested a review
from a teamSeptember 15, 2025 20:08
@sbomer
sbomer
marked this pull request as ready for review
September 15, 2025 20:08
CopilotAI
review requested due to automatic review settings
September 15, 2025 20:08
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Pull Request Overview
This pull request fixes issues related to Dynamically Accessed Members (DAM) annotation mismatch warnings on base types of type declarations. The changes remove these warnings for base type mismatches since warnings are already produced at construction of derived types. This enables the use of static methods on such types. Additionally, it includes a fix for an ILLink bug around branch removal that affects IL offset tracking during method body scanning.
Key changes include:
  • Removal of DAM mismatch warnings for base types in type declarations
  • Fix for IL offset handling during unreachable block optimization
  • Updates to test expectations reflecting the warning removal
  • Refactoring of analyzer context to better handle trim analyzer instances
Reviewed Changes
Copilot reviewed 27 out of 28 changed files in this pull request and generated 5 comments.
Show a summary per file
FileDescription
src/tools/illink/test/Mono.Linker.Tests/TestCasesRunner/ResultChecker.csComments out debug logging for test message matching
src/tools/illink/test/Mono.Linker.Tests.Cases/RequiresCapability/RequiresOnClass.csRemoves expected warnings for base type DAM mismatches
src/tools/illink/test/Mono.Linker.Tests.Cases/Generics/GenericConstraints.csAdds test case for new constraint on methods
src/tools/illink/test/Mono.Linker.Tests.Cases/DataFlow/GenericParameterWarningLocation.csUpdates warning expectations and adds constructor calls
src/tools/illink/test/Mono.Linker.Tests.Cases/DataFlow/GenericParameterDataFlowMarking.csUpdates test expectations and changes class to interface
src/tools/illink/test/Mono.Linker.Tests.Cases/DataFlow/GenericParameterDataFlow.csRemoves base type DAM mismatch warnings from tests
src/tools/illink/test/ILLink.RoslynAnalyzer.Tests/GenericsTests.csAdds test method for generic constraints
src/tools/illink/src/linker/Linker.Steps/UnreachableBlocksOptimizer.csFixes IL offset tracking during instruction replacement
src/tools/illink/src/linker/Linker.Steps/MarkStep.csRemoves base type generic argument data flow processing
src/tools/illink/src/linker/Linker.Dataflow/GenericArgumentDataFlow.csAdds new constraint handling and updates parameter processing
src/tools/illink/src/linker/Linker.Dataflow/FlowAnnotations.csAdds methods to check for generic parameter new constraints
src/tools/illink/src/ILLink.RoslynAnalyzer/TrimAnalysis/TrimAnalysisVisitor.csUpdates analyzer context usage
src/tools/illink/src/ILLink.RoslynAnalyzer/TrimAnalysis/TrimAnalysisReflectionAccessPattern.csUpdates trim analyzer reference
src/tools/illink/src/ILLink.RoslynAnalyzer/TrimAnalysis/TrimAnalysisMethodCallPattern.csUpdates trim analyzer reference
src/tools/illink/src/ILLink.RoslynAnalyzer/TrimAnalysis/TrimAnalysisGenericInstantiationPattern.csUpdates analyzer iteration
src/tools/illink/src/ILLink.RoslynAnalyzer/TrimAnalysis/TrimAnalysisAssignmentPattern.csUpdates trim analyzer reference
src/tools/illink/src/ILLink.RoslynAnalyzer/TrimAnalysis/RequireDynamicallyAccessedMembersAction.csUpdates constructor to use specific analyzer
src/tools/illink/src/ILLink.RoslynAnalyzer/TrimAnalysis/HandleCallAction.csUpdates constructor parameter
src/tools/illink/src/ILLink.RoslynAnalyzer/TrimAnalysis/GenericArgumentDataFlow.csRefactors to use specific analyzer instances
src/tools/illink/src/ILLink.RoslynAnalyzer/TrimAnalysis/FeatureCheckReturnValuePattern.csUpdates trim analyzer reference
src/tools/illink/src/ILLink.RoslynAnalyzer/RequiresUnreferencedCodeAnalyzer.csAdds generic instantiation processing
src/tools/illink/src/ILLink.RoslynAnalyzer/RequiresAnalyzerBase.csAdds generic instantiation processing base functionality
src/tools/illink/src/ILLink.RoslynAnalyzer/DynamicallyAccessedMembersAnalyzer.csRemoves base type processing
src/tools/illink/src/ILLink.RoslynAnalyzer/DataFlowAnalyzerContext.csChanges from boolean flag to specific analyzer instance
src/coreclr/tools/aot/ILCompiler.Trimming.Tests/TestCasesRunner/ResultChecker.csComments out debug logging for test message matching
src/coreclr/tools/aot/ILCompiler.Compiler/Compiler/DependencyAnalysis/DataflowAnalyzedTypeDefinitionNode.csRemoves base type generic argument data flow processing
src/coreclr/tools/aot/ILCompiler.Compiler/Compiler/Dataflow/GenericArgumentDataFlow.csAdds comments about new constraint handling
Comment threadsrc/tools/illink/src/linker/Linker.Steps/UnreachableBlocksOptimizer.cs
Comment threadsrc/tools/illink/src/linker/Linker.Steps/UnreachableBlocksOptimizer.cs
Comment threadsrc/tools/illink/src/linker/Linker.Steps/UnreachableBlocksOptimizer.cs
Comment threadsrc/tools/illink/src/linker/Linker.Steps/UnreachableBlocksOptimizer.cs
Comment threadsrc/tools/illink/src/linker/Linker.Steps/UnreachableBlocksOptimizer.cs
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It feels a bit awkward to be passing around the instances of the analyzers, but I don't have a better solution.
Comment threadsrc/tools/illink/test/Mono.Linker.Tests.Cases/DataFlow/GenericParameterDataFlow.cs
Outdated

Comment threadsrc/tools/illink/test/Mono.Linker.Tests.Cases/Generics/GenericConstraints.cs
Comment threadsrc/tools/illink/test/Mono.Linker.Tests.Cases/DataFlow/GenericParameterWarningLocation.cs
Outdated

Comment threadsrc/tools/illink/src/ILLink.RoslynAnalyzer/TrimAnalysis/GenericArgumentDataFlow.cs
Outdated

@sbomer
PR feedback
3f36272
- Use interface for generic dataflow
- Remove outdated comment
- Clarify expected warning reason
- Add Kept attributes for clarity
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ILLink: extra warning for generic parameter with new constraint and annotation

Remove DAM warning for base types/interfaces


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Remove base DAM mismatch warning on types by sbomer · Pull Request #119419 · dotnet/runtime · GitHub
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Remove base DAM mismatch warning on types - #119419
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sbomer merged 15 commits into
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sbomer:removeBaseDAMWarning
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Merged
Remove base DAM mismatch warning on types#119419
sbomer merged 15 commits into
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sbomer:removeBaseDAMWarning
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Fixes#118713(analyzer only for now)
Fixes#119290
This removes the warning for DAM annotation mismatch in the base types of a type declaration. This doesn't cause holes because we produce warnings on the construction of the derived type. Removing the warning enables the use of static methods on such a type.
While implementing this I ran into an ILLink bug around branch removal. We weren't fixing up IL offsets during branch removal, but we were using the offsets as a dictionary key when tracking known stacks during method body scanning. This includes a change to fix up IL offsets during the IL rewrite when we remove unreachable blocks.
Depends on #119291
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@sbomer
Add back interface warning
c54b8af
Moving this warning is more complicated than that for base types
because we would either need to warn on conversion to interfaces,
or warn on every constructor (for kept interface implementations).
@sbomer
Remove base warning for ILLink
a2a7bcb
@sbomersbomer
changed the title
Remove analyzer DAM warning on typesRemove base DAM mismatch warning on typesSep 8, 2025
@sbomer
Same for ILC
1bdcc9d
@sbomer
Fix ILLink generic behavior
ccd41ff
- Move new constraint processing to generic dataflow
- Take new constraint into account for requires dataflow check
@sbomer
PR feedback
e74bcea
@sbomer
Merge branch 'newConstraintHole' into removeBaseDAMWarning
c465af2
@sbomer
Add test to analyzer tests
73621ee
@sbomer
Fix offsets when rewriting IL
b2ad90e
MethodBodyScanner tracks known stacks by IL offset,
so these need to be correct when analyzing IL. We can't just
wait for cecil to update offsets for us when writing to disk.
@build-analysisbuild-analysisBot
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Sep 13, 2025

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Pull Request Overview
This pull request fixes issues related to Dynamically Accessed Members (DAM) annotation mismatch warnings on base types of type declarations. The changes remove these warnings for base type mismatches since warnings are already produced at construction of derived types. This enables the use of static methods on such types. Additionally, it includes a fix for an ILLink bug around branch removal that affects IL offset tracking during method body scanning.
Key changes include:
  • Removal of DAM mismatch warnings for base types in type declarations
  • Fix for IL offset handling during unreachable block optimization
  • Updates to test expectations reflecting the warning removal
  • Refactoring of analyzer context to better handle trim analyzer instances
Reviewed Changes
Copilot reviewed 27 out of 28 changed files in this pull request and generated 5 comments.
Show a summary per file
FileDescription
src/tools/illink/test/Mono.Linker.Tests/TestCasesRunner/ResultChecker.csComments out debug logging for test message matching
src/tools/illink/test/Mono.Linker.Tests.Cases/RequiresCapability/RequiresOnClass.csRemoves expected warnings for base type DAM mismatches
src/tools/illink/test/Mono.Linker.Tests.Cases/Generics/GenericConstraints.csAdds test case for new constraint on methods
src/tools/illink/test/Mono.Linker.Tests.Cases/DataFlow/GenericParameterWarningLocation.csUpdates warning expectations and adds constructor calls
src/tools/illink/test/Mono.Linker.Tests.Cases/DataFlow/GenericParameterDataFlowMarking.csUpdates test expectations and changes class to interface
src/tools/illink/test/Mono.Linker.Tests.Cases/DataFlow/GenericParameterDataFlow.csRemoves base type DAM mismatch warnings from tests
src/tools/illink/test/ILLink.RoslynAnalyzer.Tests/GenericsTests.csAdds test method for generic constraints
src/tools/illink/src/linker/Linker.Steps/UnreachableBlocksOptimizer.csFixes IL offset tracking during instruction replacement
src/tools/illink/src/linker/Linker.Steps/MarkStep.csRemoves base type generic argument data flow processing
src/tools/illink/src/linker/Linker.Dataflow/GenericArgumentDataFlow.csAdds new constraint handling and updates parameter processing
src/tools/illink/src/linker/Linker.Dataflow/FlowAnnotations.csAdds methods to check for generic parameter new constraints
src/tools/illink/src/ILLink.RoslynAnalyzer/TrimAnalysis/TrimAnalysisVisitor.csUpdates analyzer context usage
src/tools/illink/src/ILLink.RoslynAnalyzer/TrimAnalysis/TrimAnalysisReflectionAccessPattern.csUpdates trim analyzer reference
src/tools/illink/src/ILLink.RoslynAnalyzer/TrimAnalysis/TrimAnalysisMethodCallPattern.csUpdates trim analyzer reference
src/tools/illink/src/ILLink.RoslynAnalyzer/TrimAnalysis/TrimAnalysisGenericInstantiationPattern.csUpdates analyzer iteration
src/tools/illink/src/ILLink.RoslynAnalyzer/TrimAnalysis/TrimAnalysisAssignmentPattern.csUpdates trim analyzer reference
src/tools/illink/src/ILLink.RoslynAnalyzer/TrimAnalysis/RequireDynamicallyAccessedMembersAction.csUpdates constructor to use specific analyzer
src/tools/illink/src/ILLink.RoslynAnalyzer/TrimAnalysis/HandleCallAction.csUpdates constructor parameter
src/tools/illink/src/ILLink.RoslynAnalyzer/TrimAnalysis/GenericArgumentDataFlow.csRefactors to use specific analyzer instances
src/tools/illink/src/ILLink.RoslynAnalyzer/TrimAnalysis/FeatureCheckReturnValuePattern.csUpdates trim analyzer reference
src/tools/illink/src/ILLink.RoslynAnalyzer/RequiresUnreferencedCodeAnalyzer.csAdds generic instantiation processing
src/tools/illink/src/ILLink.RoslynAnalyzer/RequiresAnalyzerBase.csAdds generic instantiation processing base functionality
src/tools/illink/src/ILLink.RoslynAnalyzer/DynamicallyAccessedMembersAnalyzer.csRemoves base type processing
src/tools/illink/src/ILLink.RoslynAnalyzer/DataFlowAnalyzerContext.csChanges from boolean flag to specific analyzer instance
src/coreclr/tools/aot/ILCompiler.Trimming.Tests/TestCasesRunner/ResultChecker.csComments out debug logging for test message matching
src/coreclr/tools/aot/ILCompiler.Compiler/Compiler/DependencyAnalysis/DataflowAnalyzedTypeDefinitionNode.csRemoves base type generic argument data flow processing
src/coreclr/tools/aot/ILCompiler.Compiler/Compiler/Dataflow/GenericArgumentDataFlow.csAdds comments about new constraint handling
Comment threadsrc/tools/illink/src/linker/Linker.Steps/UnreachableBlocksOptimizer.cs
Comment threadsrc/tools/illink/src/linker/Linker.Steps/UnreachableBlocksOptimizer.cs
Comment threadsrc/tools/illink/src/linker/Linker.Steps/UnreachableBlocksOptimizer.cs
Comment threadsrc/tools/illink/src/linker/Linker.Steps/UnreachableBlocksOptimizer.cs
Comment threadsrc/tools/illink/src/linker/Linker.Steps/UnreachableBlocksOptimizer.cs
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It feels a bit awkward to be passing around the instances of the analyzers, but I don't have a better solution.
Comment threadsrc/tools/illink/test/Mono.Linker.Tests.Cases/DataFlow/GenericParameterDataFlow.cs
Outdated

Comment threadsrc/tools/illink/test/Mono.Linker.Tests.Cases/Generics/GenericConstraints.cs
Comment threadsrc/tools/illink/test/Mono.Linker.Tests.Cases/DataFlow/GenericParameterWarningLocation.cs
Outdated

Comment threadsrc/tools/illink/src/ILLink.RoslynAnalyzer/TrimAnalysis/GenericArgumentDataFlow.cs
Outdated

@sbomer
PR feedback
3f36272
- Use interface for generic dataflow
- Remove outdated comment
- Clarify expected warning reason
- Add Kept attributes for clarity
@sbomer
sbomer
enabled auto-merge (squash)
September 16, 2025 21:19
@jtschuster
jtschuster
disabled auto-merge
January 9, 2026 21:58
@sbomer
sbomer
merged commit a2a8bc0
into
dotnet:mainApr 14, 2026

123 checks passed

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@jtschusterjtschusterjtschuster approved these changes
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ILLink: extra warning for generic parameter with new constraint and annotation

Remove DAM warning for base types/interfaces


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@sbomer@jtschuster

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Remove base DAM mismatch warning on types by sbomer · Pull Request #119419 · dotnet/runtime · GitHub
Skip to content
Remove base DAM mismatch warning on types - #119419
Merged
sbomer merged 15 commits into
dotnet:mainfrom 
sbomer:removeBaseDAMWarning
Apr 14, 2026
Merged
Remove base DAM mismatch warning on types#119419
sbomer merged 15 commits into
dotnet:mainfrom 
sbomer:removeBaseDAMWarning
Conversation
@sbomer
@sbomersbomer
commented
Sep 6, 2025•

edited

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Fixes#118713(analyzer only for now)
Fixes#119290
This removes the warning for DAM annotation mismatch in the base types of a type declaration. This doesn't cause holes because we produce warnings on the construction of the derived type. Removing the warning enables the use of static methods on such a type.
While implementing this I ran into an ILLink bug around branch removal. We weren't fixing up IL offsets during branch removal, but we were using the offsets as a dictionary key when tracking known stacks during method body scanning. This includes a change to fix up IL offsets during the IL rewrite when we remove unreachable blocks.
Depends on #119291
@github-actionsgithub-actionsBot
added
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area-Tools-ILLink
.NET linker development as well as trimming analyzers
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Sep 6, 2025
@dotnet-policy-servicedotnet-policy-serviceBot
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linkable-framework
Issues associated with delivering a linker friendly framework
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@sbomer
Add back interface warning
c54b8af
Moving this warning is more complicated than that for base types
because we would either need to warn on conversion to interfaces,
or warn on every constructor (for kept interface implementations).
@sbomer
Remove base warning for ILLink
a2a7bcb
@sbomersbomer
changed the title
Remove analyzer DAM warning on typesRemove base DAM mismatch warning on typesSep 8, 2025
@sbomer
Same for ILC
1bdcc9d
@sbomer
Fix ILLink generic behavior
ccd41ff
- Move new constraint processing to generic dataflow
- Take new constraint into account for requires dataflow check
@sbomer
PR feedback
e74bcea
@sbomer
Merge branch 'newConstraintHole' into removeBaseDAMWarning
c465af2
@sbomer
Add test to analyzer tests
73621ee
@sbomer
Fix offsets when rewriting IL
b2ad90e
MethodBodyScanner tracks known stacks by IL offset,
so these need to be correct when analyzing IL. We can't just
wait for cecil to update offsets for us when writing to disk.
@build-analysisbuild-analysisBot
mentioned this pull request
Sep 13, 2025

Open

3 tasks
@sbomer
sbomer
requested a review
from a teamSeptember 15, 2025 20:08
@sbomer
sbomer
marked this pull request as ready for review
September 15, 2025 20:08
CopilotAI
review requested due to automatic review settings
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Pull Request Overview
This pull request fixes issues related to Dynamically Accessed Members (DAM) annotation mismatch warnings on base types of type declarations. The changes remove these warnings for base type mismatches since warnings are already produced at construction of derived types. This enables the use of static methods on such types. Additionally, it includes a fix for an ILLink bug around branch removal that affects IL offset tracking during method body scanning.
Key changes include:
  • Removal of DAM mismatch warnings for base types in type declarations
  • Fix for IL offset handling during unreachable block optimization
  • Updates to test expectations reflecting the warning removal
  • Refactoring of analyzer context to better handle trim analyzer instances
Reviewed Changes
Copilot reviewed 27 out of 28 changed files in this pull request and generated 5 comments.
Show a summary per file
FileDescription
src/tools/illink/test/Mono.Linker.Tests/TestCasesRunner/ResultChecker.csComments out debug logging for test message matching
src/tools/illink/test/Mono.Linker.Tests.Cases/RequiresCapability/RequiresOnClass.csRemoves expected warnings for base type DAM mismatches
src/tools/illink/test/Mono.Linker.Tests.Cases/Generics/GenericConstraints.csAdds test case for new constraint on methods
src/tools/illink/test/Mono.Linker.Tests.Cases/DataFlow/GenericParameterWarningLocation.csUpdates warning expectations and adds constructor calls
src/tools/illink/test/Mono.Linker.Tests.Cases/DataFlow/GenericParameterDataFlowMarking.csUpdates test expectations and changes class to interface
src/tools/illink/test/Mono.Linker.Tests.Cases/DataFlow/GenericParameterDataFlow.csRemoves base type DAM mismatch warnings from tests
src/tools/illink/test/ILLink.RoslynAnalyzer.Tests/GenericsTests.csAdds test method for generic constraints
src/tools/illink/src/linker/Linker.Steps/UnreachableBlocksOptimizer.csFixes IL offset tracking during instruction replacement
src/tools/illink/src/linker/Linker.Steps/MarkStep.csRemoves base type generic argument data flow processing
src/tools/illink/src/linker/Linker.Dataflow/GenericArgumentDataFlow.csAdds new constraint handling and updates parameter processing
src/tools/illink/src/linker/Linker.Dataflow/FlowAnnotations.csAdds methods to check for generic parameter new constraints
src/tools/illink/src/ILLink.RoslynAnalyzer/TrimAnalysis/TrimAnalysisVisitor.csUpdates analyzer context usage
src/tools/illink/src/ILLink.RoslynAnalyzer/TrimAnalysis/TrimAnalysisReflectionAccessPattern.csUpdates trim analyzer reference
src/tools/illink/src/ILLink.RoslynAnalyzer/TrimAnalysis/TrimAnalysisMethodCallPattern.csUpdates trim analyzer reference
src/tools/illink/src/ILLink.RoslynAnalyzer/TrimAnalysis/TrimAnalysisGenericInstantiationPattern.csUpdates analyzer iteration
src/tools/illink/src/ILLink.RoslynAnalyzer/TrimAnalysis/TrimAnalysisAssignmentPattern.csUpdates trim analyzer reference
src/tools/illink/src/ILLink.RoslynAnalyzer/TrimAnalysis/RequireDynamicallyAccessedMembersAction.csUpdates constructor to use specific analyzer
src/tools/illink/src/ILLink.RoslynAnalyzer/TrimAnalysis/HandleCallAction.csUpdates constructor parameter
src/tools/illink/src/ILLink.RoslynAnalyzer/TrimAnalysis/GenericArgumentDataFlow.csRefactors to use specific analyzer instances
src/tools/illink/src/ILLink.RoslynAnalyzer/TrimAnalysis/FeatureCheckReturnValuePattern.csUpdates trim analyzer reference
src/tools/illink/src/ILLink.RoslynAnalyzer/RequiresUnreferencedCodeAnalyzer.csAdds generic instantiation processing
src/tools/illink/src/ILLink.RoslynAnalyzer/RequiresAnalyzerBase.csAdds generic instantiation processing base functionality
src/tools/illink/src/ILLink.RoslynAnalyzer/DynamicallyAccessedMembersAnalyzer.csRemoves base type processing
src/tools/illink/src/ILLink.RoslynAnalyzer/DataFlowAnalyzerContext.csChanges from boolean flag to specific analyzer instance
src/coreclr/tools/aot/ILCompiler.Trimming.Tests/TestCasesRunner/ResultChecker.csComments out debug logging for test message matching
src/coreclr/tools/aot/ILCompiler.Compiler/Compiler/DependencyAnalysis/DataflowAnalyzedTypeDefinitionNode.csRemoves base type generic argument data flow processing
src/coreclr/tools/aot/ILCompiler.Compiler/Compiler/Dataflow/GenericArgumentDataFlow.csAdds comments about new constraint handling
Comment threadsrc/tools/illink/src/linker/Linker.Steps/UnreachableBlocksOptimizer.cs
Comment threadsrc/tools/illink/src/linker/Linker.Steps/UnreachableBlocksOptimizer.cs
Comment threadsrc/tools/illink/src/linker/Linker.Steps/UnreachableBlocksOptimizer.cs
Comment threadsrc/tools/illink/src/linker/Linker.Steps/UnreachableBlocksOptimizer.cs
Comment threadsrc/tools/illink/src/linker/Linker.Steps/UnreachableBlocksOptimizer.cs
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It feels a bit awkward to be passing around the instances of the analyzers, but I don't have a better solution.
Comment threadsrc/tools/illink/test/Mono.Linker.Tests.Cases/DataFlow/GenericParameterDataFlow.cs
Outdated

Comment threadsrc/tools/illink/test/Mono.Linker.Tests.Cases/Generics/GenericConstraints.cs
Comment threadsrc/tools/illink/test/Mono.Linker.Tests.Cases/DataFlow/GenericParameterWarningLocation.cs
Outdated

Comment threadsrc/tools/illink/src/ILLink.RoslynAnalyzer/TrimAnalysis/GenericArgumentDataFlow.cs
Outdated

@sbomer
PR feedback
3f36272
- Use interface for generic dataflow
- Remove outdated comment
- Clarify expected warning reason
- Add Kept attributes for clarity
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ILLink: extra warning for generic parameter with new constraint and annotation

Remove DAM warning for base types/interfaces


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Remove base DAM mismatch warning on types by sbomer · Pull Request #119419 · dotnet/runtime · GitHub
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Remove base DAM mismatch warning on types - #119419
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sbomer merged 15 commits into
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sbomer:removeBaseDAMWarning
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Merged
Remove base DAM mismatch warning on types#119419
sbomer merged 15 commits into
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Fixes#118713(analyzer only for now)
Fixes#119290
This removes the warning for DAM annotation mismatch in the base types of a type declaration. This doesn't cause holes because we produce warnings on the construction of the derived type. Removing the warning enables the use of static methods on such a type.
While implementing this I ran into an ILLink bug around branch removal. We weren't fixing up IL offsets during branch removal, but we were using the offsets as a dictionary key when tracking known stacks during method body scanning. This includes a change to fix up IL offsets during the IL rewrite when we remove unreachable blocks.
Depends on #119291
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@sbomer
Add back interface warning
c54b8af
Moving this warning is more complicated than that for base types
because we would either need to warn on conversion to interfaces,
or warn on every constructor (for kept interface implementations).
@sbomer
Remove base warning for ILLink
a2a7bcb
@sbomersbomer
changed the title
Remove analyzer DAM warning on typesRemove base DAM mismatch warning on typesSep 8, 2025
@sbomer
Same for ILC
1bdcc9d
@sbomer
Fix ILLink generic behavior
ccd41ff
- Move new constraint processing to generic dataflow
- Take new constraint into account for requires dataflow check
@sbomer
PR feedback
e74bcea
@sbomer
Merge branch 'newConstraintHole' into removeBaseDAMWarning
c465af2
@sbomer
Add test to analyzer tests
73621ee
@sbomer
Fix offsets when rewriting IL
b2ad90e
MethodBodyScanner tracks known stacks by IL offset,
so these need to be correct when analyzing IL. We can't just
wait for cecil to update offsets for us when writing to disk.
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Pull Request Overview
This pull request fixes issues related to Dynamically Accessed Members (DAM) annotation mismatch warnings on base types of type declarations. The changes remove these warnings for base type mismatches since warnings are already produced at construction of derived types. This enables the use of static methods on such types. Additionally, it includes a fix for an ILLink bug around branch removal that affects IL offset tracking during method body scanning.
Key changes include:
  • Removal of DAM mismatch warnings for base types in type declarations
  • Fix for IL offset handling during unreachable block optimization
  • Updates to test expectations reflecting the warning removal
  • Refactoring of analyzer context to better handle trim analyzer instances
Reviewed Changes
Copilot reviewed 27 out of 28 changed files in this pull request and generated 5 comments.
Show a summary per file
FileDescription
src/tools/illink/test/Mono.Linker.Tests/TestCasesRunner/ResultChecker.csComments out debug logging for test message matching
src/tools/illink/test/Mono.Linker.Tests.Cases/RequiresCapability/RequiresOnClass.csRemoves expected warnings for base type DAM mismatches
src/tools/illink/test/Mono.Linker.Tests.Cases/Generics/GenericConstraints.csAdds test case for new constraint on methods
src/tools/illink/test/Mono.Linker.Tests.Cases/DataFlow/GenericParameterWarningLocation.csUpdates warning expectations and adds constructor calls
src/tools/illink/test/Mono.Linker.Tests.Cases/DataFlow/GenericParameterDataFlowMarking.csUpdates test expectations and changes class to interface
src/tools/illink/test/Mono.Linker.Tests.Cases/DataFlow/GenericParameterDataFlow.csRemoves base type DAM mismatch warnings from tests
src/tools/illink/test/ILLink.RoslynAnalyzer.Tests/GenericsTests.csAdds test method for generic constraints
src/tools/illink/src/linker/Linker.Steps/UnreachableBlocksOptimizer.csFixes IL offset tracking during instruction replacement
src/tools/illink/src/linker/Linker.Steps/MarkStep.csRemoves base type generic argument data flow processing
src/tools/illink/src/linker/Linker.Dataflow/GenericArgumentDataFlow.csAdds new constraint handling and updates parameter processing
src/tools/illink/src/linker/Linker.Dataflow/FlowAnnotations.csAdds methods to check for generic parameter new constraints
src/tools/illink/src/ILLink.RoslynAnalyzer/TrimAnalysis/TrimAnalysisVisitor.csUpdates analyzer context usage
src/tools/illink/src/ILLink.RoslynAnalyzer/TrimAnalysis/TrimAnalysisReflectionAccessPattern.csUpdates trim analyzer reference
src/tools/illink/src/ILLink.RoslynAnalyzer/TrimAnalysis/TrimAnalysisMethodCallPattern.csUpdates trim analyzer reference
src/tools/illink/src/ILLink.RoslynAnalyzer/TrimAnalysis/TrimAnalysisGenericInstantiationPattern.csUpdates analyzer iteration
src/tools/illink/src/ILLink.RoslynAnalyzer/TrimAnalysis/TrimAnalysisAssignmentPattern.csUpdates trim analyzer reference
src/tools/illink/src/ILLink.RoslynAnalyzer/TrimAnalysis/RequireDynamicallyAccessedMembersAction.csUpdates constructor to use specific analyzer
src/tools/illink/src/ILLink.RoslynAnalyzer/TrimAnalysis/HandleCallAction.csUpdates constructor parameter
src/tools/illink/src/ILLink.RoslynAnalyzer/TrimAnalysis/GenericArgumentDataFlow.csRefactors to use specific analyzer instances
src/tools/illink/src/ILLink.RoslynAnalyzer/TrimAnalysis/FeatureCheckReturnValuePattern.csUpdates trim analyzer reference
src/tools/illink/src/ILLink.RoslynAnalyzer/RequiresUnreferencedCodeAnalyzer.csAdds generic instantiation processing
src/tools/illink/src/ILLink.RoslynAnalyzer/RequiresAnalyzerBase.csAdds generic instantiation processing base functionality
src/tools/illink/src/ILLink.RoslynAnalyzer/DynamicallyAccessedMembersAnalyzer.csRemoves base type processing
src/tools/illink/src/ILLink.RoslynAnalyzer/DataFlowAnalyzerContext.csChanges from boolean flag to specific analyzer instance
src/coreclr/tools/aot/ILCompiler.Trimming.Tests/TestCasesRunner/ResultChecker.csComments out debug logging for test message matching
src/coreclr/tools/aot/ILCompiler.Compiler/Compiler/DependencyAnalysis/DataflowAnalyzedTypeDefinitionNode.csRemoves base type generic argument data flow processing
src/coreclr/tools/aot/ILCompiler.Compiler/Compiler/Dataflow/GenericArgumentDataFlow.csAdds comments about new constraint handling
Comment threadsrc/tools/illink/src/linker/Linker.Steps/UnreachableBlocksOptimizer.cs
Comment threadsrc/tools/illink/src/linker/Linker.Steps/UnreachableBlocksOptimizer.cs
Comment threadsrc/tools/illink/src/linker/Linker.Steps/UnreachableBlocksOptimizer.cs
Comment threadsrc/tools/illink/src/linker/Linker.Steps/UnreachableBlocksOptimizer.cs
Comment threadsrc/tools/illink/src/linker/Linker.Steps/UnreachableBlocksOptimizer.cs
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It feels a bit awkward to be passing around the instances of the analyzers, but I don't have a better solution.
Comment threadsrc/tools/illink/test/Mono.Linker.Tests.Cases/DataFlow/GenericParameterDataFlow.cs
Outdated

Comment threadsrc/tools/illink/test/Mono.Linker.Tests.Cases/Generics/GenericConstraints.cs
Comment threadsrc/tools/illink/test/Mono.Linker.Tests.Cases/DataFlow/GenericParameterWarningLocation.cs
Outdated

Comment threadsrc/tools/illink/src/ILLink.RoslynAnalyzer/TrimAnalysis/GenericArgumentDataFlow.cs
Outdated

@sbomer
PR feedback
3f36272
- Use interface for generic dataflow
- Remove outdated comment
- Clarify expected warning reason
- Add Kept attributes for clarity
@sbomer
sbomer
enabled auto-merge (squash)
September 16, 2025 21:19
@jtschuster
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January 9, 2026 21:58
@sbomer
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merged commit a2a8bc0
into
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123 checks passed

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@jtschusterjtschusterjtschuster approved these changes
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ILLink: extra warning for generic parameter with new constraint and annotation

Remove DAM warning for base types/interfaces


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Remove base DAM mismatch warning on types by sbomer · Pull Request #119419 · dotnet/runtime · GitHub
Skip to content
Remove base DAM mismatch warning on types - #119419
Merged
sbomer merged 15 commits into
dotnet:mainfrom 
sbomer:removeBaseDAMWarning
Apr 14, 2026
Merged
Remove base DAM mismatch warning on types#119419
sbomer merged 15 commits into
dotnet:mainfrom 
sbomer:removeBaseDAMWarning
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Sep 6, 2025•

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Fixes#118713(analyzer only for now)
Fixes#119290
This removes the warning for DAM annotation mismatch in the base types of a type declaration. This doesn't cause holes because we produce warnings on the construction of the derived type. Removing the warning enables the use of static methods on such a type.
While implementing this I ran into an ILLink bug around branch removal. We weren't fixing up IL offsets during branch removal, but we were using the offsets as a dictionary key when tracking known stacks during method body scanning. This includes a change to fix up IL offsets during the IL rewrite when we remove unreachable blocks.
Depends on #119291
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.NET linker development as well as trimming analyzers
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Issues associated with delivering a linker friendly framework
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@sbomer
Add back interface warning
c54b8af
Moving this warning is more complicated than that for base types
because we would either need to warn on conversion to interfaces,
or warn on every constructor (for kept interface implementations).
@sbomer
Remove base warning for ILLink
a2a7bcb
@sbomersbomer
changed the title
Remove analyzer DAM warning on typesRemove base DAM mismatch warning on typesSep 8, 2025
@sbomer
Same for ILC
1bdcc9d
@sbomer
Fix ILLink generic behavior
ccd41ff
- Move new constraint processing to generic dataflow
- Take new constraint into account for requires dataflow check
@sbomer
PR feedback
e74bcea
@sbomer
Merge branch 'newConstraintHole' into removeBaseDAMWarning
c465af2
@sbomer
Add test to analyzer tests
73621ee
@sbomer
Fix offsets when rewriting IL
b2ad90e
MethodBodyScanner tracks known stacks by IL offset,
so these need to be correct when analyzing IL. We can't just
wait for cecil to update offsets for us when writing to disk.
@build-analysisbuild-analysisBot
mentioned this pull request
Sep 13, 2025

Open

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marked this pull request as ready for review
September 15, 2025 20:08
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Pull Request Overview
This pull request fixes issues related to Dynamically Accessed Members (DAM) annotation mismatch warnings on base types of type declarations. The changes remove these warnings for base type mismatches since warnings are already produced at construction of derived types. This enables the use of static methods on such types. Additionally, it includes a fix for an ILLink bug around branch removal that affects IL offset tracking during method body scanning.
Key changes include:
  • Removal of DAM mismatch warnings for base types in type declarations
  • Fix for IL offset handling during unreachable block optimization
  • Updates to test expectations reflecting the warning removal
  • Refactoring of analyzer context to better handle trim analyzer instances
Reviewed Changes
Copilot reviewed 27 out of 28 changed files in this pull request and generated 5 comments.
Show a summary per file
FileDescription
src/tools/illink/test/Mono.Linker.Tests/TestCasesRunner/ResultChecker.csComments out debug logging for test message matching
src/tools/illink/test/Mono.Linker.Tests.Cases/RequiresCapability/RequiresOnClass.csRemoves expected warnings for base type DAM mismatches
src/tools/illink/test/Mono.Linker.Tests.Cases/Generics/GenericConstraints.csAdds test case for new constraint on methods
src/tools/illink/test/Mono.Linker.Tests.Cases/DataFlow/GenericParameterWarningLocation.csUpdates warning expectations and adds constructor calls
src/tools/illink/test/Mono.Linker.Tests.Cases/DataFlow/GenericParameterDataFlowMarking.csUpdates test expectations and changes class to interface
src/tools/illink/test/Mono.Linker.Tests.Cases/DataFlow/GenericParameterDataFlow.csRemoves base type DAM mismatch warnings from tests
src/tools/illink/test/ILLink.RoslynAnalyzer.Tests/GenericsTests.csAdds test method for generic constraints
src/tools/illink/src/linker/Linker.Steps/UnreachableBlocksOptimizer.csFixes IL offset tracking during instruction replacement
src/tools/illink/src/linker/Linker.Steps/MarkStep.csRemoves base type generic argument data flow processing
src/tools/illink/src/linker/Linker.Dataflow/GenericArgumentDataFlow.csAdds new constraint handling and updates parameter processing
src/tools/illink/src/linker/Linker.Dataflow/FlowAnnotations.csAdds methods to check for generic parameter new constraints
src/tools/illink/src/ILLink.RoslynAnalyzer/TrimAnalysis/TrimAnalysisVisitor.csUpdates analyzer context usage
src/tools/illink/src/ILLink.RoslynAnalyzer/TrimAnalysis/TrimAnalysisReflectionAccessPattern.csUpdates trim analyzer reference
src/tools/illink/src/ILLink.RoslynAnalyzer/TrimAnalysis/TrimAnalysisMethodCallPattern.csUpdates trim analyzer reference
src/tools/illink/src/ILLink.RoslynAnalyzer/TrimAnalysis/TrimAnalysisGenericInstantiationPattern.csUpdates analyzer iteration
src/tools/illink/src/ILLink.RoslynAnalyzer/TrimAnalysis/TrimAnalysisAssignmentPattern.csUpdates trim analyzer reference
src/tools/illink/src/ILLink.RoslynAnalyzer/TrimAnalysis/RequireDynamicallyAccessedMembersAction.csUpdates constructor to use specific analyzer
src/tools/illink/src/ILLink.RoslynAnalyzer/TrimAnalysis/HandleCallAction.csUpdates constructor parameter
src/tools/illink/src/ILLink.RoslynAnalyzer/TrimAnalysis/GenericArgumentDataFlow.csRefactors to use specific analyzer instances
src/tools/illink/src/ILLink.RoslynAnalyzer/TrimAnalysis/FeatureCheckReturnValuePattern.csUpdates trim analyzer reference
src/tools/illink/src/ILLink.RoslynAnalyzer/RequiresUnreferencedCodeAnalyzer.csAdds generic instantiation processing
src/tools/illink/src/ILLink.RoslynAnalyzer/RequiresAnalyzerBase.csAdds generic instantiation processing base functionality
src/tools/illink/src/ILLink.RoslynAnalyzer/DynamicallyAccessedMembersAnalyzer.csRemoves base type processing
src/tools/illink/src/ILLink.RoslynAnalyzer/DataFlowAnalyzerContext.csChanges from boolean flag to specific analyzer instance
src/coreclr/tools/aot/ILCompiler.Trimming.Tests/TestCasesRunner/ResultChecker.csComments out debug logging for test message matching
src/coreclr/tools/aot/ILCompiler.Compiler/Compiler/DependencyAnalysis/DataflowAnalyzedTypeDefinitionNode.csRemoves base type generic argument data flow processing
src/coreclr/tools/aot/ILCompiler.Compiler/Compiler/Dataflow/GenericArgumentDataFlow.csAdds comments about new constraint handling
Comment threadsrc/tools/illink/src/linker/Linker.Steps/UnreachableBlocksOptimizer.cs
Comment threadsrc/tools/illink/src/linker/Linker.Steps/UnreachableBlocksOptimizer.cs
Comment threadsrc/tools/illink/src/linker/Linker.Steps/UnreachableBlocksOptimizer.cs
Comment threadsrc/tools/illink/src/linker/Linker.Steps/UnreachableBlocksOptimizer.cs
Comment threadsrc/tools/illink/src/linker/Linker.Steps/UnreachableBlocksOptimizer.cs
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It feels a bit awkward to be passing around the instances of the analyzers, but I don't have a better solution.
Comment threadsrc/tools/illink/test/Mono.Linker.Tests.Cases/DataFlow/GenericParameterDataFlow.cs
Outdated

Comment threadsrc/tools/illink/test/Mono.Linker.Tests.Cases/Generics/GenericConstraints.cs
Comment threadsrc/tools/illink/test/Mono.Linker.Tests.Cases/DataFlow/GenericParameterWarningLocation.cs
Outdated

Comment threadsrc/tools/illink/src/ILLink.RoslynAnalyzer/TrimAnalysis/GenericArgumentDataFlow.cs
Outdated

@sbomer
PR feedback
3f36272
- Use interface for generic dataflow
- Remove outdated comment
- Clarify expected warning reason
- Add Kept attributes for clarity
@sbomer
sbomer
enabled auto-merge (squash)
September 16, 2025 21:19
@jtschuster
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disabled auto-merge
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@sbomer
sbomer
merged commit a2a8bc0
into
dotnet:mainApr 14, 2026

123 checks passed

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@jtschusterjtschusterjtschuster approved these changes
@marek-safarmarek-safarAwaiting requested review from marek-safar
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ILLink: extra warning for generic parameter with new constraint and annotation

Remove DAM warning for base types/interfaces


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