Skip to content

Don't warn if we can't find the backing field in trim tools #119820

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Merged
jtschuster merged 12 commits into from
Sep 22, 2025
Merged

Don't warn if we can't find the backing field in trim tools #119820

Show file tree
Hide file tree
Changes from 6 commits
Commits
Show all changes
12 commits
Select commit Hold shift + click to select a range
f576285
Don't warn if we can't find the backing field
jtschuster Sep 17, 2025
41d4bfb
Re-add warning for mismatched backing fields found in get vs set
jtschuster Sep 17, 2025
250c973
Merge branch 'main' of https://github.com/dotnet/runtime into AutoPro…
jtschuster Sep 17, 2025
7201195
Don't warn for mismatching backing fields
jtschuster Sep 17, 2025
79738ce
Apply suggestion from @Copilot
jtschuster Sep 17, 2025
076c3de
Apply suggestion from @Copilot
jtschuster Sep 17, 2025
16ff81b
PR Feedback: only check for existing backing field annotation when th…
jtschuster Sep 18, 2025
bf25161
Merge branch 'AutoPropBackingFieldNoWarn' of https://github.com/jtsch…
jtschuster Sep 18, 2025
b14b64f
Merge branch 'main' of https://github.com/dotnet/runtime into AutoPro…
jtschuster Sep 18, 2025
38c4684
Merge branch 'main' into AutoPropBackingFieldNoWarn
jtschuster Sep 18, 2025
0698bd6
Merge branch 'AutoPropBackingFieldNoWarn' of https://github.com/jtsch…
jtschuster Sep 18, 2025
0f3eb4e
Fix analyzer tests
jtschuster Sep 18, 2025
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
39 changes: 8 additions & 31 deletions src/coreclr/tools/aot/ILCompiler.Compiler/Compiler/Dataflow/FlowAnnotations.cs
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -592,41 +592,18 @@ protected override TypeAnnotations CreateValueFromKey(TypeDesc key)
}
}

if (IsAutoProperty(property))
FieldDesc? backingField = backingFieldFromSetter ?? backingFieldFromGetter;
if (backingField is not null)
{
FieldDesc? backingField = null;
if ((property.SetMethod is not null
&& property.SetMethod.HasCustomAttribute("System.Runtime.CompilerServices", "CompilerGeneratedAttribute")
&& backingFieldFromSetter is null)
|| (property.GetMethod is not null
&& property.GetMethod.HasCustomAttribute("System.Runtime.CompilerServices", "CompilerGeneratedAttribute")
&& backingFieldFromGetter is null))
if (annotatedFields.Any(a => a.Field == backingField))
Comment thread
jtschuster marked this conversation as resolved.
Outdated
Comment thread
sbomer marked this conversation as resolved.
Outdated
{
// We failed to find the backing field of an auto-property accessor
_logger.LogWarning(property, DiagnosticId.DynamicallyAccessedMembersCouldNotFindBackingField, property.GetDisplayName());
_logger.LogWarning(backingField, DiagnosticId.DynamicallyAccessedMembersOnPropertyConflictsWithBackingField, property.GetDisplayName(), backingField.GetDisplayName());
}
else if (backingFieldFromGetter is not null && backingFieldFromSetter is not null
&& backingFieldFromSetter != backingFieldFromGetter)
else if (!(backingFieldFromGetter is not null
Comment thread
sbomer marked this conversation as resolved.
Outdated
&& backingFieldFromSetter is not null
&& backingFieldFromGetter != backingFieldFromSetter))
{
// We found two different backing fields for the getter and the setter
_logger.LogWarning(property, DiagnosticId.DynamicallyAccessedMembersCouldNotFindBackingField, property.GetDisplayName());
}
else
{
// We either have a single auto-property accessor or both accessors point to the same backing field
backingField = backingFieldFromSetter ?? backingFieldFromGetter;
}

if (backingField != null)
{
if (annotatedFields.Any(a => a.Field == backingField))
{
_logger.LogWarning(backingField, DiagnosticId.DynamicallyAccessedMembersOnPropertyConflictsWithBackingField, property.GetDisplayName(), backingField.GetDisplayName());
}
else
{
annotatedFields.Add(new FieldAnnotation(backingField, annotation));
}
annotatedFields.Add(new FieldAnnotation(backingField, annotation));
}
Comment thread
jtschuster marked this conversation as resolved.
}
}
Expand Down
6 changes: 3 additions & 3 deletions src/tools/illink/src/ILLink.RoslynAnalyzer/TrimAnalysis/FlowAnnotations.cs
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -117,11 +117,11 @@ internal static DynamicallyAccessedMemberTypes GetFieldAnnotation(IFieldSymbol f
if (!field.OriginalDefinition.Type.IsTypeInterestingForDataflow(isByRef: field.RefKind is not RefKind.None))
return DynamicallyAccessedMemberTypes.None;

if (field.AssociatedSymbol is IPropertySymbol property)
if (field.AssociatedSymbol is IPropertySymbol property
&& property.IsAutoProperty())
{
// If this is an auto property, we get the property annotation
if (property.IsAutoProperty())
return property.GetDynamicallyAccessedMemberTypes();
return property.GetDynamicallyAccessedMemberTypes();
}

return field.GetDynamicallyAccessedMemberTypes();
Expand Down
2 changes: 1 addition & 1 deletion src/tools/illink/src/ILLink.Shared/DiagnosticId.cs
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -101,7 +101,7 @@ public enum DiagnosticId
XmlInvalidValueForAttributeActionForResource = 2039,
XmlCouldNotFindResourceToRemoveInAssembly = 2040,
DynamicallyAccessedMembersIsNotAllowedOnMethods = 2041,
DynamicallyAccessedMembersCouldNotFindBackingField = 2042,
unused_DynamicallyAccessedMembersCouldNotFindBackingField = 2042,
Comment thread
jtschuster marked this conversation as resolved.
DynamicallyAccessedMembersConflictsBetweenPropertyAndAccessor = 2043,
XmlCouldNotFindAnyTypeInNamespace = 2044,
AttributeIsReferencedButTrimmerRemoveAllInstances = 2045,
Expand Down
40 changes: 9 additions & 31 deletions src/tools/illink/src/linker/Linker.Dataflow/FlowAnnotations.cs
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -433,41 +433,19 @@ TypeAnnotations BuildTypeAnnotations(TypeDefinition type)
}
}

if (IsAutoProperty(property))

FieldDefinition? backingField = backingFieldFromSetter ?? backingFieldFromGetter;
if (backingField is not null)
{
FieldDefinition? backingField = null;
// If it's an annotated auto-prop, we should be able to find the compiler generated field
if ((property.SetMethod is not null
&& property.SetMethod.IsCompilerGenerated()
&& backingFieldFromSetter is null)
|| (property.GetMethod is not null
&& property.GetMethod.IsCompilerGenerated()
&& backingFieldFromGetter is null))
{
// We failed to find the backing field of an auto-property accessor
_context.LogWarning(property, DiagnosticId.DynamicallyAccessedMembersCouldNotFindBackingField, property.GetDisplayName());
}
else if (backingFieldFromGetter is not null && backingFieldFromSetter is not null
&& backingFieldFromSetter != backingFieldFromGetter)
{
// We found two different backing fields for the getter and the setter
_context.LogWarning(property, DiagnosticId.DynamicallyAccessedMembersCouldNotFindBackingField, property.GetDisplayName());
}
else
if (annotatedFields.Any(a => a.Field == backingField))
{
// We either have a single auto-property accessor or both accessors point to the same backing field
backingField = backingFieldFromSetter ?? backingFieldFromGetter;
_context.LogWarning(backingField, DiagnosticId.DynamicallyAccessedMembersOnPropertyConflictsWithBackingField, property.GetDisplayName(), backingField.GetDisplayName());
}
if (backingField != null)
if (!(backingFieldFromGetter is not null
&& backingFieldFromSetter is not null
&& backingFieldFromGetter != backingFieldFromSetter))
{
if (annotatedFields.Any(a => a.Field == backingField))
{
_context.LogWarning(backingField, DiagnosticId.DynamicallyAccessedMembersOnPropertyConflictsWithBackingField, property.GetDisplayName(), backingField.GetDisplayName());
}
else
{
annotatedFields.Add(new FieldAnnotation(backingField, annotation));
}
annotatedFields.Add(new FieldAnnotation(backingField, annotation));
}
}
}
Expand Down
10 changes: 0 additions & 10 deletions src/tools/illink/test/Mono.Linker.Tests.Cases/DataFlow/PropertyDataFlow.cs
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -288,8 +288,6 @@ public void TestPropertyWithDifferentBackingFields()
private Type PropertyWithDifferentBackingFields_SetterField;

// Analyzer doesn't try to detect backing fields of properties: https://github.com/dotnet/linker/issues/2273
[ExpectedWarning("IL2042",
"Mono.Linker.Tests.Cases.DataFlow.PropertyDataFlow.TestAutomaticPropagationType.PropertyWithDifferentBackingFields", Tool.Trimmer | Tool.NativeAot, "Requires IL")]
[ExpectedWarning("IL2078",
nameof(TestAutomaticPropagationType) + "." + nameof(PropertyWithDifferentBackingFields) + ".get",
"Type", Tool.Analyzer, "")]
Expand Down Expand Up @@ -959,7 +957,6 @@ class AutoPropertyUnrecognizedField
private Type Property_BackingField;

[DynamicallyAccessedMembers(DynamicallyAccessedMemberTypes.PublicConstructors)]
[ExpectedWarning("IL2042", Tool.NativeAot | Tool.Trimmer, "Requires IL")] // Can't find backing field
public Type Property
{
[CompilerGenerated]
Expand All @@ -980,7 +977,6 @@ public Type Property
}

[DynamicallyAccessedMembers(DynamicallyAccessedMemberTypes.PublicConstructors)]
[ExpectedWarning("IL2042", Tool.NativeAot | Tool.Trimmer, "Requires IL")] // Can't find backing field
public Type PropertyAutoSet
{
[CompilerGenerated]
Expand All @@ -995,10 +991,8 @@ public Type PropertyAutoSet
}

[DynamicallyAccessedMembers(DynamicallyAccessedMemberTypes.PublicConstructors)]
[ExpectedWarning("IL2042", Tool.NativeAot | Tool.Trimmer, "Requires IL")] // Can't find backing field
public Type PropertyAutoGet
{
[ExpectedWarning("IL2078", ["return value", nameof(PropertyAutoGet), "BackingField"], producedBy: Tool.NativeAot | Tool.Trimmer, "Requires IL")]
get;
[CompilerGenerated]
set
Expand All @@ -1010,7 +1004,6 @@ public Type PropertyAutoGet
}

[DynamicallyAccessedMembers(DynamicallyAccessedMemberTypes.PublicConstructors)]
[ExpectedWarning("IL2042", Tool.NativeAot | Tool.Trimmer, "Requires IL")] // Can't find backing field
public Type PropertyManualSet
{
[CompilerGenerated]
Expand All @@ -1025,7 +1018,6 @@ public Type PropertyManualSet
}

[DynamicallyAccessedMembers(DynamicallyAccessedMemberTypes.PublicConstructors)]
[ExpectedWarning("IL2042", Tool.NativeAot | Tool.Trimmer, "Requires IL")] // Can't find backing field
public Type PropertyManualGet
{
[ExpectedWarning("IL2078", "return value", nameof(Property_BackingField))]
Expand All @@ -1040,7 +1032,6 @@ public Type PropertyManualGet
}

[DynamicallyAccessedMembers(DynamicallyAccessedMemberTypes.PublicConstructors)]
[ExpectedWarning("IL2042", Tool.NativeAot | Tool.Trimmer, "Requires IL")] // Can't find backing field
public Type PropertyOnlyGet
{
[CompilerGenerated]
Expand All @@ -1054,7 +1045,6 @@ public Type PropertyOnlyGet
}

[DynamicallyAccessedMembers(DynamicallyAccessedMemberTypes.PublicConstructors)]
[ExpectedWarning("IL2042", nameof(PropertyOnlySet), Tool.NativeAot | Tool.Trimmer, "Requires IL")] // Can't find backing field
public Type PropertyOnlySet
{
[CompilerGenerated]
Expand Down
Loading