[net11.0] Merge main into net11.0.

.github/workflows/maestro-changelog.yml

@@ -17,17 +17,17 @@ jobs:
     if: github.event.pull_request.user.login == 'dotnet-maestro[bot]'
 
     steps:
+    - uses: actions/checkout@3d3c42e5aac5ba805825da76410c181273ba90b1 # v7.0.1
+      with:
+        persist-credentials: false
     - uses: actions/setup-dotnet@a98b56852c35b8e3190ac28c8c2271da59106c68 # v6.0.0
       with:
-        dotnet-version: '9'
+        global-json-file: ./global.json
 
     - name: 'Compute changelog'
       run: |
         set -exo pipefail
-        git clone https://github.com/spouliot/dotnet-tools
-        cd dotnet-tools/changelog
-        dotnet build
-        ./bin/Debug/net9.0/changelog https://github.com/$GITHUB_REPOSITORY/pull/${GITHUB_REF_NAME/\/*/} > /tmp/changelog.txt 2>&1
+        dotnet run --project scripts/changelog/changelog.csproj --verbosity quiet -- https://github.com/$GITHUB_REPOSITORY/pull/${GITHUB_REF_NAME/\/*/} /tmp/changelog.txt
 
     - name: 'Add changelog'
       uses: actions/github-script@3a2844b7e9c422d3c10d287c895573f7108da1b3 # v9.0.0
@@ -45,7 +45,9 @@ jobs:
             issue_number: context.issue.number
           }).then ((comments) =>
           {
-            const changelogComment = comments.find(comment => comment.body.includes (".net ChangeLog for") && comment.user.login == 'github-actions[bot]')
+            const changelogComment = comments.find(comment =>
+              (comment.body.includes (".NET Changelog for") || comment.body.includes (".net ChangeLog for")) &&
+              comment.user.login == 'github-actions[bot]')
             if (changelogComment)
               commentId = changelogComment.id
           })

.github/workflows/zizmor.yml

@@ -29,6 +29,6 @@ jobs:
           echo "files=$files" >> "$GITHUB_OUTPUT"
 
       - name: Run zizmor
-        uses: zizmorcore/zizmor-action@6599ee8b7a49aef6a770f63d261d214911a7ce02 # v0.6.0
+        uses: zizmorcore/zizmor-action@3dc1ecc9bcb9e94e9b2c709687979e1298497054 # v0.6.2
         with:
           inputs: ${{ steps.find-files.outputs.files }}

Directory.Build.props

@@ -12,7 +12,7 @@
 		<!-- Fix transient dependency issue found by component governance 4.7.0 -> 4.7.2 brought by Microsoft.Build package -->
 		<SystemDrawingCommonPackageVersion>4.7.2</SystemDrawingCommonPackageVersion>
 		<!-- Fix transient dependency issue found by component governance 4.7.0 -> 4.7.1 brought by Microsoft.Build.Tasks.Core package -->
-		<SystemSecurityCryptographyXmlPackageVersion>8.0.0</SystemSecurityCryptographyXmlPackageVersion>
+		<SystemSecurityCryptographyXmlPackageVersion>8.0.4</SystemSecurityCryptographyXmlPackageVersion>
 
 		<ClangSharpPackageVersion>21.1.8.3</ClangSharpPackageVersion>
 		<ICSharpCodeNRefactoryPackageVersion>5.5.1</ICSharpCodeNRefactoryPackageVersion>

docs/building-apps/build-properties.md

@@ -197,6 +197,27 @@ The default value of this property `false` in .NET 9, and `true` in .NET 10+.
 > [!NOTE]
 > File an issue if you find that you need to disable this feature, as it's possible that the option to disable it will be removed in future.
 
+## CheckForIllegalCrossThreadCalls
+
+Controls whether the UI thread checks (the `[NS|UI]Application.EnsureUIThread`
+calls the generated bindings emit for UI code) are performed.
+
+When set to `true`, the checks are enabled: accessing UI API off the UI thread
+throws an exception. When set to `false`, the checks are disabled.
+
+This property is emitted as the `ObjCRuntime.Runtime.CheckForIllegalCrossThreadCalls`
+runtime feature switch, so it takes effect even when trimming is disabled: the
+`[NS|UI]Application.CheckForIllegalCrossThreadCalls` field reflects the property
+value at runtime, and the checks are enabled or disabled accordingly.
+
+When trimming is enabled and the checks are disabled, ILLink additionally stubs
+the `[NS|UI]Application.EnsureUIThread` method body and trims away the
+`CheckForIllegalCrossThreadCalls` field, making the app slightly smaller and
+faster.
+
+If this value is not specified, the checks are kept in debug builds and removed
+in release builds.
+
 ## CodesignAllocate
 
 The path to the `codesign_allocate` tool.
@@ -660,6 +681,13 @@ Default: true
 
 Where the generated source from the generator are saved.
 
+## GenerateTrustedPlatformAssemblies
+
+A boolean property that specifies whether the trusted platform assembly list is
+generated at build time instead of discovered when the app launches.
+
+The default value is `false` for debug builds and `true` for other builds.
+
 ## GetApplicationArtifactsDependsOn
 
 A semi-colon delimited property that can be used to extend the

docs/website/optimizations.md

@@ -16,8 +16,15 @@ Xamarin.iOS and Xamarin.Mac apps.
 
 ## Remove UIApplication.EnsureUIThread / NSApplication.EnsureUIThread
 
-Removes calls to [UIApplication.EnsureUIThread][1] (for Xamarin.iOS) or
-`NSApplication.EnsureUIThread` (for Xamarin.Mac).
+> [!NOTE]
+> This optimization has been replaced by the `CheckForIllegalCrossThreadCalls`
+> MSBuild property, which sets the
+> `ObjCRuntime.Runtime.CheckForIllegalCrossThreadCalls` trimmer feature switch.
+> The `--optimize=[+|-]remove-uithread-checks` flag is no longer applied and has
+> no effect.
+
+Removes calls to [UIApplication.EnsureUIThread][1] (for .NET for iOS) or
+`NSApplication.EnsureUIThread` (for .NET for macOS).
 
 This optimization will change the following type of code:
 
@@ -43,7 +50,7 @@ methods with the `[BindingImpl (BindingImplOptions.Optimizable)]` attribute.
 
 By default it's enabled for release builds.
 
-The default behavior can be overridden by passing `--optimize=[+|-]remove-uithread-checks` to mtouch/mmp.
+Set the `CheckForIllegalCrossThreadCalls` MSBuild property to override the default behavior.
 
 [1]: /dotnet/api/UIKit.UIApplication.EnsureUIThread
 

dotnet/targets/Xamarin.Shared.Sdk.props

@@ -41,35 +41,48 @@
 		<_UseNativeAot Condition="'$(PublishAot)' == 'true' And '$(_IsPublishing)' == 'true'">true</_UseNativeAot>
 
 		<!--
-			On .NET 11+, make the trimmable-static registrar the default for NativeAOT (it used to be
-			managed-static). This has to be set here, at evaluation time, and not only in the SelectRegistrar
-			target (which runs later), because the static _SkipILLink / _PostprocessAssembliesAfterIlc gates
-			check the registrar at evaluation time.
-
-			This is deliberately scoped to NativeAOT: the trimmable-static registrar only produces a *smaller*
-			app under NativeAOT (where the TypeMap feature and the post-ILC registrar reorder let us trim the
-			registered binding surface). On Mono/CoreCLR the trimmable-static registrar keeps the whole
-			registered NSObject surface and makes apps 2-3x *larger*, so those runtimes keep managed-static.
+			These have to be computed here, before the registrar defaults below, because those check
+			$(UseMonoRuntime) at evaluation time.
 		-->
-		<Registrar Condition="'$(Registrar)' == '' And '$(_UseNativeAot)' == 'true' And $([MSBuild]::VersionGreaterThanOrEquals($(TargetFrameworkVersion), '11.0'))">trimmable-static</Registrar>
+		<UseMonoRuntime Condition=" '$(UseMonoRuntime)' == ''">false</UseMonoRuntime>
 
 		<!--
-			Enable the PrepareAssemblies flow by default for NativeAOT on .NET 11+. This runs our custom linker
-			steps in the assembly-preparer, and for the (NativeAOT-default) trimmable-static registrar it also
-			generates the native static registrar code *after* the NativeAOT compiler (ILC) has run (see
-			_PostprocessAssembliesAfterIlc), so the registrar can drop the native code for UnmanagedCallersOnly
-			trampolines ILC trimmed away (an app-size optimization).
+			On .NET 11+, make the trimmable-static registrar the default for both CoreCLR and NativeAOT (it used
+			to be managed-static, and before that the trimmable-static registrar was only the default for
+			NativeAOT). This has to be set here, at evaluation time, and not only in the SelectRegistrar target
+			(which runs later), because the static _SkipILLink / _PostprocessAssembliesAfterIlc gates check the
+			registrar at evaluation time.
+
+			Mono keeps the managed-static registrar.
 		-->
-		<PrepareAssemblies Condition="'$(PrepareAssemblies)' == '' And '$(_UseNativeAot)' == 'true' And $([MSBuild]::VersionGreaterThanOrEquals($(TargetFrameworkVersion), '11.0'))">true</PrepareAssemblies>
+		<Registrar Condition="'$(Registrar)' == '' And '$(UseMonoRuntime)' != 'true' And $([MSBuild]::VersionGreaterThanOrEquals($(TargetFrameworkVersion), '11.0'))">trimmable-static</Registrar>
+
+		<!--
+			Enable the PrepareAssemblies flow by default for CoreCLR and NativeAOT on .NET 11+. This runs our
+			custom linker steps in the assembly-preparer. For NativeAOT it additionally generates the native
+			static registrar code *after* the NativeAOT compiler (ILC) has run (see
+			_PostprocessAssembliesAfterIlc, which is NativeAOT-only), so the registrar can drop the native code
+			for the UnmanagedCallersOnly trampolines ILC trimmed away (an app-size optimization).
+
+			This is *required* for the trimmable-static registrar to produce a small app: the assembly-preparer
+			writes the generated type map assemblies to disk (marked with [AssemblyMetadata ("IsTrimmable", "True")])
+			before the trimmer runs, so the trimmer treats them as ordinary trimmable input assemblies. Without it
+			the type map assemblies are created from inside the trimmer, where they end up with the 'copy' assembly
+			action - which means they're not trimmed, and since they reference every Objective-C type in the app,
+			nothing else can be trimmed either (that made apps ~3x larger).
+
+			The $(Registrar) check means a CoreCLR app that explicitly opts back in to the managed-static
+			registrar doesn't get PrepareAssemblies enabled - that combination makes apps *larger*. NativeAOT
+			always gets PrepareAssemblies regardless of the registrar, which is the pre-existing behavior.
+		-->
+		<PrepareAssemblies Condition="'$(PrepareAssemblies)' == '' And '$(UseMonoRuntime)' != 'true' And ('$(_UseNativeAot)' == 'true' Or '$(Registrar)' == 'trimmable-static') And $([MSBuild]::VersionGreaterThanOrEquals($(TargetFrameworkVersion), '11.0'))">true</PrepareAssemblies>
 
 		<!--
 			PostProcessAssemblies defaults to $(PrepareAssemblies) (see Xamarin.Shared.targets), but the static
 			_PostprocessAssembliesAfterIlc gate reads it at evaluation time - earlier than that default runs - so
 			apply the same $(PrepareAssemblies) default here too, otherwise the gate wouldn't see it.
 		-->
-		<PostProcessAssemblies Condition="'$(PostProcessAssemblies)' == '' And '$(_UseNativeAot)' == 'true' And $([MSBuild]::VersionGreaterThanOrEquals($(TargetFrameworkVersion), '11.0'))">$(PrepareAssemblies)</PostProcessAssemblies>
-
-		<UseMonoRuntime Condition=" '$(UseMonoRuntime)' == ''">false</UseMonoRuntime>
+		<PostProcessAssemblies Condition="'$(PostProcessAssemblies)' == '' And '$(UseMonoRuntime)' != 'true' And ('$(_UseNativeAot)' == 'true' Or '$(Registrar)' == 'trimmable-static') And $([MSBuild]::VersionGreaterThanOrEquals($(TargetFrameworkVersion), '11.0'))">$(PrepareAssemblies)</PostProcessAssemblies>
 
 		<AfterMicrosoftNETSdkTargets>$(AfterMicrosoftNETSdkTargets);$(MSBuildThisFileDirectory)Microsoft.$(_PlatformName).Sdk.targets</AfterMicrosoftNETSdkTargets>