[NativeAOT] Make the trimmable typemap the default#12121
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NativeAOT now defaults to and requires _AndroidTypeMapImplementation=trimmable: - Microsoft.Android.Sdk.NativeAOT.targets: default managed -> trimmable; always run _PreTrimmingFixLegacyDesignerUpdateItems before NativeCompile. - Xamarin.Android.Common.targets: error if NativeAOT is used with a non-trimmable typemap; run the post-ILLink AssemblyModifierPipeline for NativeAOT+trimmable (split out _GetAfterILLinkAdditionalStepsInputs); skip the project proguard config for NativeAOT+trimmable. - Microsoft.Android.Sdk.TypeMap.Trimmable.targets: disable ManagedPeerNativeRegistration for trimmable; depend on IlcDynamicBuildPropertyDependencies on NativeAOT. - JNIEnvInit / JreRuntime: NativeAOT now throws if the trimmable type map is not used, and the reflection-backed managers are wrapped in IL2026-suppressed helpers so Mono.Android and the NativeAOT runtime host build clean under trimming. Test infrastructure for follow-up NativeAOT triage: - BaseTest: IgnoreNativeAotLinkedAssemblyChecks / IgnoreOnNativeAot helpers. - Mono.Android-Tests: add a TrimmableTypeMapUnsupported excluded category. Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
…mmable path _PreTrimmingFixLegacyDesignerUpdateItems is only defined in the LlvmIr typemap targets, which are not imported for trimmable builds. Referencing it from _AndroidRunNativeCompileDependsOn unconditionally broke NativeAOT (now trimmable by default) with MSB4057. Restore the per-typemap condition so the trimmable path only depends on NativeCompile. Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
NativeAOT trims with ILC and does not produce illink's obj/<config>/<rid>/linked/
directory, so tests that inspect linked assemblies (or assert the obsolete
PreserveAttribute IL6001 warning, or use the unsupported 'Lowercase' package naming
policy) cannot run as-is on NativeAOT. Guard them with the BaseTest helpers:
- LinkerTests: AndroidAddKeepAlives, AndroidUseNegotiateAuthentication,
PreserveIX509TrustManagerSubclasses, PreserveServices (linked/ inspection),
WarnWithReferenceToPreserveAttribute (IL6001).
- BuildTest2: NativeAOT (linked/Mono.Android.dll inspection), BuildReleaseArm64.
- IncrementalBuildTest: AppProjectTargetsDoNotBreak, LinkAssembliesNoShrink (linked/),
ChangePackageNamingPolicy ('Lowercase' policy unsupported on trimmable).
Verified locally: PreserveIX509TrustManagerSubclasses(NativeAOT) now reports Skipped
instead of DirectoryNotFoundException, while the CoreCLR case still passes.
Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
…ault - XASdkTests: NativeAOT is now warning-clean (the reflection-manager IL3050/IL3053 warnings are gone), so assert no warnings instead of one. - ManifestTest.ExportedErrorMessage: the trimmable manifest generator orders merged components differently, so assert the coded AMM0000 error for NativeAOT without the exact manifest line/column (verified: NativeAOT case passes). - BuildWithLibraryTests.ProjectDependencies: the trimmable typemap trims Java Callable Wrappers for library types that are never instantiated, so the unused LibraryB JCWs are absent from classes.dex by design; skip the NativeAOT case (verified locally: the scrc64-named JCW .class files are generated but trimmed out of the dex). Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
NativeAOT release builds emit a proguard mapping.txt in the output directory (confirmed in local NativeAOT build outputs), so add it to the expected file list for the NativeAOT release case of DotNetBuild. Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
…chable Drop the hard error that required _AndroidTypeMapImplementation=trimmable on NativeAOT. For now this PR only flips the NativeAOT default to trimmable while keeping the existing managed/llvm-ir configurations reachable (the runtime keeps its ManagedTypeManager / JavaMarshalValueManager fallbacks). Removing the non-trimmable NativeAOT paths and re-introducing the error will be done in a separate PR. Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
This test inspected illink's linked/Mono.Android.dll and the legacy ManagedTypeMapping class to verify the managed type-map. With the trimmable typemap now the NativeAOT default, ILC produces neither that linked/ output nor the ManagedTypeMapping type, so the test no longer applies. Remove it rather than leaving a permanently-ignored test; a DGML-based type-map check for NativeAOT can be added as a follow-up. Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
The test asserts the build fails with XA8000 for SkiaSharp's unresolved @styleable/SKCanvasView, which relies on FixLegacyResourceDesignerStep. That legacy resource-designer step is intentionally not run on the trimmable typemap path (the NativeAOT default), so the diagnostic isn't emitted and the NativeAOT case no longer applies. Skip it on NativeAOT via the IgnoreOnNativeAot helper. Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
R8 shrinks bound library Java types (JavaSourceJarTest, JavaSourceTestExtension) out of classes.dex on the trimmable typemap path because the proguard keep config is incomplete on NativeAOT, so the class-presence assertions fail. Skip the NativeAOT case via IgnoreOnNativeAot until the underlying proguard-keep bug is fixed. Tracked by #11774. Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
The trimmable typemap generates additional Java Callable Wrappers that trip XA0102 lint warnings. Ignore on NativeAOT until #11774 is resolved. Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
The trimmable NativeAOT path generates its ProGuard/R8 ACW keep rules from the ILC DGML into proguard_project_references.cfg (_ProguardProjectConfiguration) via GenerateNativeAotProguardConfiguration, and deliberately leaves R8's proguard_project_primary.cfg empty so that references.cfg is the sole source of ACW keeps. However _CalculateProguardConfigurationFiles excluded _ProguardProjectConfiguration for NativeAOT+trimmable, so R8 received no ACW keep rules and tree-shook every JCW/ACW (e.g. UncaughtExceptionMarshaler) out of classes.dex. The app then crashed at startup in JavaInteropRuntime.init with: java.lang.ClassNotFoundException: scrc64...UncaughtExceptionMarshaler Drop the trimmable exclusion so the generated keep rules reach R8. Verified on an arm64 emulator with CheckJNI enabled: the HelloWorld NativeAOT (trimmable) sample now retains the ACW JCWs in classes.dex and launches to MainActivity without crashing. Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
Adds NativeAotKeepsRuntimeAcwJavaTypesUnderR8, which builds a Release NativeAOT app with r8 and asserts that classes.dex still contains the runtime UncaughtExceptionMarshaler ACW kept by the generated NativeAOT ProGuard rules. If those keep rules are missing, R8 tree-shakes the runtime JCWs and the app crashes at startup inside JavaInteropRuntime.init. Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
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Pull request overview
This PR switches NativeAOT builds to use the trimmable typemap by default, aligning the NativeAOT pipeline with the trimmable typemap runtime model and updating build/test infrastructure to account for NativeAOT/ILC differences vs ILLink-based flows.
Changes:
- Flip NativeAOT default
_AndroidTypeMapImplementationfrommanaged→trimmable. - Configure trimmable typemap runtimeconfig to disable
Java.Interop.RuntimeFeature.ManagedPeerNativeRegistration. - Update/skip/replace several tests that relied on ILLink
linked/outputs or legacy behavior; add a regression test ensuring runtime ACW/JCW Java types are kept under R8 for NativeAOT.
Show a summary per file
| File | Description |
|---|---|
| tests/MSBuildDeviceIntegration/Tests/InstallAndRunTests.cs | Skips a SkiaSharp device test on NativeAOT due to legacy designer-fix behavior differences on the trimmable path. |
| src/Xamarin.Android.Build.Tasks/Tests/Xamarin.Android.Build.Tests/Utilities/BaseTest.cs | Adds helper skip methods for NativeAOT-specific limitations (no ILLink linked/ output; other fundamental behavior differences). |
| src/Xamarin.Android.Build.Tasks/Tests/Xamarin.Android.Build.Tests/Tasks/LinkerTests.cs | Skips tests that inspect ILLink linked/ outputs (or ILLink-only warnings) when running under NativeAOT. |
| src/Xamarin.Android.Build.Tasks/Tests/Xamarin.Android.Build.Tests/ManifestTest.cs | Adjusts AMM0000 assertion for NativeAOT to avoid line-number coupling due to manifest layout differences. |
| src/Xamarin.Android.Build.Tasks/Tests/Xamarin.Android.Build.Tests/IncrementalBuildTest.cs | Skips/guards NativeAOT cases where behavior is intentionally unsupported (e.g., AndroidPackageNamingPolicy=Lowercase with trimmable typemap). |
| src/Xamarin.Android.Build.Tasks/Tests/Xamarin.Android.Build.Tests/BuildWithLibraryTests.cs | Skips a dependency/DEX assertion on NativeAOT due to trimmable typemap trimming unused JCWs. |
| src/Xamarin.Android.Build.Tasks/Tests/Xamarin.Android.Build.Tests/BuildTest2.cs | Removes an obsolete NativeAOT typemap test based on ILLink linked/ output; adds an R8 keep-rule regression test for runtime ACWs on NativeAOT. |
| src/Xamarin.Android.Build.Tasks/Tests/Xamarin.Android.Build.Tests/BuildTest.cs | Updates expected build outputs for NativeAOT Release to include mapping.txt; skips a lint test on NativeAOT due to known trimmable-JCW lint warnings. |
| src/Xamarin.Android.Build.Tasks/Tests/Xamarin.Android.Build.Tests/BindingBuildTest.cs | Skips a binding + AndroidJavaSource scenario on NativeAOT due to missing R8 keeps (tracked issue). |
| src/Xamarin.Android.Build.Tasks/Microsoft.Android.Sdk/targets/Microsoft.Android.Sdk.TypeMap.Trimmable.targets | Sets Java.Interop.RuntimeFeature.ManagedPeerNativeRegistration=false for trimmable typemap runs. |
| src/Xamarin.Android.Build.Tasks/Microsoft.Android.Sdk/targets/Microsoft.Android.Sdk.NativeAOT.targets | Makes trimmable the default _AndroidTypeMapImplementation for NativeAOT builds. |
Copilot's findings
- Files reviewed: 11/11 changed files
- Comments generated: 1
The XA4212 "custom IJavaObject not supported" diagnostic is produced by the Cecil-based XAJavaTypeScanner, which runs on the managed typemap path (via AssemblyModifierPipeline in _RunAfterILLinkAdditionalSteps) and the llvm-ir path (which passes ErrorOnCustomJavaObject to its generator). Now that the trimmable typemap is the NativeAOT default, the type scan happens in the System.Reflection.Metadata-based TrimmableTypeMapGenerator, which does not yet perform the custom-IJavaObject check, so XA4212 is never raised and the build wrongly succeeds. Skip the NativeAOT case with a documented follow-up until the diagnostic is added to the trimmable generator. Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com> Copilot-Session: 94f450c7-781d-4019-a56c-fae1c456b9a7
…veAOT This test verifies the _RunAfterILLinkAdditionalSteps target and its afterlink/ output. That target is intentionally skipped on the trimmable typemap path (Condition "... '$(_AndroidTypeMapImplementation)' != 'trimmable'"), because the trimmable path generates the typemap at compile time in _GenerateTrimmableTypeMap. The test is unchanged from main and passed only because NativeAOT used to default to the managed typemap. Now that trimmable is the NativeAOT default, the target is skipped and no afterlink/ directory is produced, so skip the NativeAOT case (same pattern as other NativeAOT test skips in this PR). Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com> Copilot-Session: 94f450c7-781d-4019-a56c-fae1c456b9a7
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This was referenced Jul 16, 2026
The trimmable typemap defaulted _AndroidTrimmableTypeMapMaxArrayRank to 3
whenever dynamic code was unavailable (NativeAOT / PublishAot), which emits
per-element-type __ArrayMapRank{N} array-proxy types. Those proxies are dead
code at runtime: array and collection creation now goes through the AOT-safe
SafeArrayFactory / ValueTypeFactory (added in #12030), and
TrimmableTypeMap.TryGetArrayProxy has no callers.
Generating them only bloats NativeAOT ILC compilation. On multi-ABI apps this
pushed ILC past the test-harness build cap, timing out NativeAOT lanes
(Check9PatchFilesAreProcessed, WorkManager, BundleToolTests) that passed
quickly (5-13 min) before this default became NativeAOT.
Default MaxArrayRank to 0 on every runtime (still overridable via
$(_AndroidTrimmableTypeMapMaxArrayRank)). This is a subset of the codegen
removal in #12126; the per-type JavaPeerContainerFactory<T> bloat is not
addressed here and still needs #12126.
Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
Copilot-Session: da26833c-c9ea-41a6-b8d7-7a87a60ce8fc
…mmable-typemap-default-nativeaot-2 # Conflicts: # src/Xamarin.Android.Build.Tasks/Microsoft.Android.Sdk/targets/Microsoft.Android.Sdk.TypeMap.Trimmable.targets
Ensure additional JCW directories contribute concrete Java files to _CompileJava inputs instead of a literal wildcard path. Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com> Copilot-Session: 187b207a-083b-461e-9071-e9aab61c9d07
Pass both the standard generated Java source directory and compile-in-place JCW directories to Android lint so manifest classes are resolved. Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com> Copilot-Session: 187b207a-083b-461e-9071-e9aab61c9d07
Update CustomApplicationClassAndMultiDex to inspect NativeAOT generated Java in typemap/java while retaining the legacy CoreCLR path. Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com> Copilot-Session: 187b207a-083b-461e-9071-e9aab61c9d07
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Goal
Make the trimmable typemap the default typemap for NativeAOT.
Supersedes #11822. That PR was based directly on
main; this one is instead stacked on #12030 (dev/simonrozsival/android-trimmable-revisit-arrays-generic-collections), which reworks the AOT-safe array and collection factories. Rebasing onto #12030 let me drop the array-proxy / boxed-nullable /System.String-array-element commits (now handled by #12030'sMakeArrayType/MakeGenericTypefactories) plus other work that has since landed on that branch, leaving just the focused NativeAOT default flip and its test adjustments.Contributes to #10794, #11012, #8724, #10788, #10793.
Change map
Core enablement
Microsoft.Android.Sdk.NativeAOT.targets— default_AndroidTypeMapImplementationmanaged→trimmable.Xamarin.Android.Common.targets— run the post-ILLinkAssemblyModifierPipelinefor NativeAOT+trimmable; skip the project proguard config for NativeAOT+trimmable. (All gated ontrimmable, somanaged/llvm-irNativeAOT is unchanged.)Microsoft.Android.Sdk.TypeMap.Trimmable.targets— disableManagedPeerNativeRegistrationfor trimmable._PreTrimmingFixLegacyDesignerUpdateItemsoff the trimmable path.Tests
BaseTest—IgnoreNativeAotLinkedAssemblyChecks/IgnoreOnNativeAothelpers.linked/output (LinkerTests,IncrementalBuildTest,BuildTest2); delete the obsoleteBuildTest2.NativeAOTtypemap test.DotNetBuildexpectsmapping.txtfor NativeAOT release; add a NativeAOT regression test for R8-kept runtime ACWs.XA4212custom-IJavaObjectdiagnostic is skipped on the NativeAOT (trimmable) path here for simplicity; the root-cause fix that emits it from the trimmable generator moved to follow-up [TrimmableTypeMap] Emit XA4212 for custom IJavaObject types on the trimmable path #12132.Local validation
Microsoft.Android.Sdk.TrimmableTypeMap.Tests→ 614 pass.Follow-up
IJavaObjectdetection to the trimmable typemap generator and re-enables the test skipped here.Draft until CI confirms the full matrix (device tests + baselines).