Make Android SDK trimming safe

[marek-safar]

As part of the .NET6 effort we are making the .NET Runtime trimming safe allow developers to annotate their libraries to be also trimming safe. As Android SDK is one of the primary workloads which will always use linker and cares about the size it's important to resolve any linker warnings which the developers would experience when enabling linker analyzers.

The work to enable the linker analyzer is not yet simple and the effort to change that is tracked at https://github.com/dotnet/sdk/issues/15962

[jonpryor]

Context: #5856 (comment)
Context: #5878

Warnings that need to be fixed include:

ILLink warning IL2072: Java.Interop.JniRuntime.SetMarshalMemberBuilder(JniRuntime.CreationOptions): '#0' argument does not satisfy 'DynamicallyAccessedMemberTypes.PublicParameterlessConstructor' in call to 'System.Object System.Activator::CreateInstance(System.Type)'. The return value of method 'System.Reflection.Assembly.GetType(String)' does not have matching annotations. The source value must declare at least the same requirements as those declared on the target location it is assigned to.
ILLink warning IL2026: Java.Interop.JniRuntime.SetMarshalMemberBuilder(JniRuntime.CreationOptions): Using method 'System.Reflection.Assembly.GetType(String)' which has 'RequiresUnreferencedCodeAttribute' can break functionality when trimming application code. Types might be removed.
ILLink warning IL2067: Java.Interop.JniRuntime.JniTypeManager.FindAndCallRegisterMethod(Type,JniNativeMethodRegistrationArguments): 'type' argument does not satisfy 'DynamicallyAccessedMemberTypes.PublicMethods', 'DynamicallyAccessedMemberTypes.NonPublicMethods' in call to 'System.Reflection.RuntimeReflectionExtensions.GetRuntimeMethods(Type)'. The parameter 'marshalType' of method 'Java.Interop.JniRuntime.JniTypeManager.FindAndCallRegisterMethod(Type,JniNativeMethodRegistrationArguments)' does not have matching annotations. The source value must declare at least the same requirements as those declared on the target location it is assigned to.
ILLink warning IL2072: Java.Interop.JniRuntime.JniTypeManager.TryLoadJniMarshalMethods(JniType,Type,String): '#0' argument does not satisfy 'DynamicallyAccessedMemberTypes.PublicMethods' in call to 'System.Reflection.MethodInfo System.Reflection.RuntimeReflectionExtensions::GetRuntimeMethod(System.Type,System.String,System.Type[])'. The return value of method 'System.Type.GetNestedType(String,BindingFlags)' does not have matching annotations. The source value must declare at least the same requirements as those declared on the target location it is assigned to.
ILLink warning IL2070: Java.Interop.JniRuntime.JniTypeManager.TryLoadJniMarshalMethods(JniType,Type,String): 'this' argument does not satisfy 'DynamicallyAccessedMemberTypes.NonPublicNestedTypes' in call to 'System.Type.GetNestedType(String,BindingFlags)'. The parameter 'type' of method 'Java.Interop.JniRuntime.JniTypeManager.TryLoadJniMarshalMethods(JniType,Type,String)' does not have matching annotations. The source value must declare at least the same requirements as those declared on the target location it is assigned to.
ILLink warning IL2070: Java.Interop.JniRuntime.JniValueManager.GetActivationConstructor(Type): 'this' argument does not satisfy 'DynamicallyAccessedMemberTypes.PublicConstructors', 'DynamicallyAccessedMemberTypes.NonPublicConstructors' in call to 'System.Type.GetConstructors(BindingFlags)'. The parameter 'type' of method 'Java.Interop.JniRuntime.JniValueManager.GetActivationConstructor(Type)' does not have matching annotations. The source value must declare at least the same requirements as those declared on the target location it is assigned to.
ILLink warning IL2060: Java.Interop.JniRuntime.JniValueManager.GetObjectArrayMarshaler(Type): Call to 'System.Reflection.MethodInfo System.Reflection.MethodInfo::MakeGenericMethod(System.Type[])' can not be statically analyzed. It's not possible to guarantee the availability of requirements of the generic method.
ILLink warning IL2072: Java.Interop.JniRuntime.JniValueManager.GetValueMarshaler(Type): '#0' argument does not satisfy 'DynamicallyAccessedMemberTypes.PublicParameterlessConstructor' in call to 'System.Object System.Activator::CreateInstance(System.Type)'. The return value of method 'Java.Interop.JniValueMarshalerAttribute.MarshalerType.get' does not have matching annotations. The source value must declare at least the same requirements as those declared on the target location it is assigned to.
ILLink warning IL2072: Java.Interop.JniRuntime.JniValueManager.GetValueMarshaler(Type): '#0' argument does not satisfy 'DynamicallyAccessedMemberTypes.PublicParameterlessConstructor' in call to 'System.Object System.Activator::CreateInstance(System.Type)'. The return value of method 'Java.Interop.JniValueMarshalerAttribute.MarshalerType.get' does not have matching annotations. The source value must declare at least the same requirements as those declared on the target location it is assigned to.
ILLink warning IL2057: Java.Interop.ManagedPeer.Construct(IntPtr,IntPtr,IntPtr,IntPtr,IntPtr,IntPtr): Unrecognized value passed to the parameter 'typeName' of method 'System.Type.GetType(String,Boolean)'. It's not possible to guarantee the availability of the target type.
ILLink warning IL2075: Java.Interop.ManagedPeer.Construct(IntPtr,IntPtr,IntPtr,IntPtr,IntPtr,IntPtr): 'this' argument does not satisfy 'DynamicallyAccessedMemberTypes.PublicConstructors' in call to 'System.Type.GetConstructor(Type[])'. The return value of method 'System.Type.GetType(String,Boolean)' does not have matching annotations. The source value must declare at least the same requirements as those declared on the target location it is assigned to.
ILLink warning IL2057: Java.Interop.ManagedPeer.GetParameterTypes(String): Unrecognized value passed to the parameter 'typeName' of method 'System.Type.GetType(String,Boolean)'. It's not possible to guarantee the availability of the target type.
ILLink warning IL2057: Java.Interop.ManagedPeer.RegisterNativeMembers(IntPtr,IntPtr,IntPtr,IntPtr,IntPtr): Unrecognized value passed to the parameter 'typeName' of method 'System.Type.GetType(String,Boolean)'. It's not possible to guarantee the availability of the target type.
ILLink warning IL2075: Android.Runtime.AndroidTypeManager.CreateDynamicCallback(MethodInfo): 'this' argument does not satisfy 'DynamicallyAccessedMemberTypes.PublicMethods' in call to 'System.Type.GetMethod(String)'. The return value of method 'System.Reflection.Assembly.GetType(String)' does not have matching annotations. The source value must declare at least the same requirements as those declared on the target location it is assigned to.
ILLink warning IL2026: Android.Runtime.AndroidTypeManager.CreateDynamicCallback(MethodInfo): Using method 'System.Reflection.Assembly.GetType(String)' which has 'RequiresUnreferencedCodeAttribute' can break functionality when trimming application code. Types might be removed.
ILLink warning IL2057: Android.Runtime.AndroidTypeManager.RegisterNativeMembers(JniType,Type,String): Unrecognized value passed to the parameter 'typeName' of method 'System.Type.GetType(String,Boolean)'. It's not possible to guarantee the availability of the target type.
ILLink warning IL2072: Android.Runtime.AndroidTypeManager.RegisterNativeMembers(JniType,Type,String): 'target' argument does not satisfy 'All' in call to 'System.Delegate.CreateDelegate(Type,Type,String)'. The return value of method 'System.Type System.Type::get_BaseType()' does not have matching annotations. The source value must declare at least the same requirements as those declared on the target location it is assigned to.
ILLink warning IL2072: Android.Runtime.AndroidTypeManager.RegisterNativeMembers(JniType,Type,String): 'target' argument does not satisfy 'All' in call to 'System.Delegate.CreateDelegate(Type,Type,String)'. The return value of method 'System.Type.GetType(String,Boolean)' does not have matching annotations. The source value must declare at least the same requirements as those declared on the target location it is assigned to.
ILLink warning IL2070: Android.Runtime.AndroidTypeManager.RegisterNativeMembers(JniType,Type,String): 'this' argument does not satisfy 'DynamicallyAccessedMemberTypes.PublicMethods', 'DynamicallyAccessedMemberTypes.NonPublicMethods' in call to 'System.Type.GetMethods(BindingFlags)'. The parameter 'type' of method 'Android.Runtime.AndroidTypeManager.RegisterNativeMembers(JniType,Type,String)' does not have matching annotations. The source value must declare at least the same requirements as those declared on the target location it is assigned to.
ILLink warning IL2067: Android.Runtime.AndroidTypeManager.RegisterNativeMembers(JniType,Type,String): 'target' argument does not satisfy 'All' in call to 'System.Delegate.CreateDelegate(Type,Type,String)'. The parameter 'type' of method 'Android.Runtime.AndroidTypeManager.RegisterNativeMembers(JniType,Type,String)' does not have matching annotations. The source value must declare at least the same requirements as those declared on the target location it is assigned to.
ILLink warning IL2070: Java.Interop.JavaConvert.GetJniHandleConverterForType(Type): 'this' argument does not satisfy 'DynamicallyAccessedMemberTypes.PublicMethods' in call to 'System.Type.GetMethod(String,BindingFlags)'. The parameter 't' of method 'Java.Interop.JavaConvert.GetJniHandleConverterForType(Type)' does not have matching annotations. The source value must declare at least the same requirements as those declared on the target location it is assigned to.
ILLink warning IL2055: Java.Interop.JavaObjectExtensions.GetHelperType(Type,String): Call to 'System.Type.MakeGenericType(Type[])' can not be statically analyzed. It's not possible to guarantee the availability of requirements of the generic type.
ILLink warning IL2026: Java.Interop.JavaObjectExtensions.GetHelperType(Type,String): Using method 'System.Reflection.Assembly.GetType(String)' which has 'RequiresUnreferencedCodeAttribute' can break functionality when trimming application code. Types might be removed.
ILLink warning IL2026: Java.Interop.JavaObjectExtensions.GetHelperType(Type,String): Using method 'System.Reflection.Assembly.GetType(String)' which has 'RequiresUnreferencedCodeAttribute' can break functionality when trimming application code. Types might be removed.
ILLink warning IL2057: Android.Runtime.JNIEnv.RegisterJniNatives(IntPtr,Int32,IntPtr,IntPtr,Int32): Unrecognized value passed to the parameter 'typeName' of method 'System.Type.GetType(String)'. It's not possible to guarantee the availability of the target type.
ILLink warning IL2026: Android.Runtime.ResourceIdManager.GetResourceTypeFromAssembly(Assembly): Using method 'System.Reflection.Assembly.GetType(String)' which has 'RequiresUnreferencedCodeAttribute' can break functionality when trimming application code. Types might be removed.
ILLink warning IL2075: Android.Runtime.ResourceIdManager.UpdateIdValues(): 'this' argument does not satisfy 'DynamicallyAccessedMemberTypes.PublicMethods' in call to 'System.Type.GetMethod(String)'. The return value of method 'Android.Runtime.ResourceIdManager.GetResourceTypeFromAssembly(Assembly)' does not have matching annotations. The source value must declare at least the same requirements as those declared on the target location it is assigned to.
ILLink warning IL2070: Java.Interop.TypeManager.CreateProxy(Type,IntPtr,JniHandleOwnership): 'this' argument does not satisfy 'DynamicallyAccessedMemberTypes.PublicConstructors', 'DynamicallyAccessedMemberTypes.NonPublicConstructors' in call to 'System.Type.GetConstructor(BindingFlags,Binder,Type[],ParameterModifier[])'. The parameter 'type' of method 'Java.Interop.TypeManager.CreateProxy(Type,IntPtr,JniHandleOwnership)' does not have matching annotations. The source value must declare at least the same requirements as those declared on the target location it is assigned to.
ILLink warning IL2070: Java.Interop.TypeManager.CreateProxy(Type,IntPtr,JniHandleOwnership): 'this' argument does not satisfy 'DynamicallyAccessedMemberTypes.PublicConstructors', 'DynamicallyAccessedMemberTypes.NonPublicConstructors' in call to 'System.Type.GetConstructor(BindingFlags,Binder,Type[],ParameterModifier[])'. The parameter 'type' of method 'Java.Interop.TypeManager.CreateProxy(Type,IntPtr,JniHandleOwnership)' does not have matching annotations. The source value must declare at least the same requirements as those declared on the target location it is assigned to.
ILLink warning IL2057: Java.Interop.TypeManager.GetParameterTypes(String): Unrecognized value passed to the parameter 'typeName' of method 'System.Type.GetType(String,Boolean)'. It's not possible to guarantee the availability of the target type.
ILLink warning IL2057: Java.Interop.TypeManager.n_Activate(IntPtr,IntPtr,IntPtr,IntPtr,IntPtr,IntPtr): Unrecognized value passed to the parameter 'typeName' of method 'System.Type.GetType(String,Boolean)'. It's not possible to guarantee the availability of the target type.
ILLink warning IL2075: Java.Interop.TypeManager.n_Activate(IntPtr,IntPtr,IntPtr,IntPtr,IntPtr,IntPtr): 'this' argument does not satisfy 'DynamicallyAccessedMemberTypes.PublicConstructors' in call to 'System.Type.GetConstructor(Type[])'. The return value of method 'System.Type.GetType(String,Boolean)' does not have matching annotations. The source value must declare at least the same requirements as those declared on the target location it is assigned to.

[jonathanpeppers]

The latest list as of 1aac4a0, is a lot shorter now:

external\Java.Interop\src\Java.Interop\Java.Interop\JniRuntime.JniMarshalMemberBuilder.cs(48,4): warning IL2026: Java.Interop.JniRuntime.SetMarshalMemberBuilder(JniRuntime.CreationOptions): Using method 'System.Reflection.Assembly.GetType(String)' which has 'RequiresUnreferencedCodeAttribute' can break functionality when trimming application code. Types might be removed.
src\Mono.Android\Android.Runtime\AndroidRuntime.cs(294,5): warning IL2026: Android.Runtime.AndroidTypeManager.CreateDynamicCallback(MethodInfo): Using method 'System.Reflection.Assembly.GetType(String)' which has 'RequiresUnreferencedCodeAttribute' can break functionality when trimming application code. Types might be removed.
src\Mono.Android\Java.Interop\JavaObjectExtensions.cs(131,5): warning IL2026: Java.Interop.JavaObjectExtensions.GetHelperType(Type,String): Using method 'System.Reflection.Assembly.GetType(String)' which has 'RequiresUnreferencedCodeAttribute' can break functionality when trimming application code. Types might be removed.
src\Mono.Android\Java.Interop\JavaObjectExtensions.cs(136,4): warning IL2026: Java.Interop.JavaObjectExtensions.GetHelperType(Type,String): Using method 'System.Reflection.Assembly.GetType(String)' which has 'RequiresUnreferencedCodeAttribute' can break functionality when trimming application code. Types might be removed.
src\Mono.Android\Android.Runtime\ResourceIdManager.cs(37,6): warning IL2026: Android.Runtime.ResourceIdManager.GetResourceTypeFromAssembly(Assembly): Using method 'System.Reflection.Assembly.GetType(String)' which has 'RequiresUnreferencedCodeAttribute' can break functionality when trimming application code. Types might be removed.