[release/7.0.3xx] [msbuild] Re-aot referencing assemblies. Fixes #17708.

dotnet/targets/Xamarin.Shared.Sdk.targets

@@ -1038,8 +1038,7 @@
 	<Target Name="_AOTCompile"
 			Condition="'$(_RunAotCompiler)' == 'true'"
 			DependsOnTargets="$(_AOTCompileDependsOn)"
-			Inputs="@(_AssembliesToAOT)"
-			Outputs="@(_AssembliesToAOT -> '%(ObjectFile)');@(_AssembliesToAOT -> '%(LLVMFile)');">
+		>
 
 		<AOTCompile
 			SessionId="$(BuildSessionId)"

msbuild/Xamarin.Localization.MSBuild/MSBStrings.resx

@@ -1467,4 +1467,33 @@
         </comment>
     </data>
 
+    <data name="E7116" xml:space="preserve">
+        <value>The assembly {0} does not provide an 'ObjectFile' metadata.</value>
+        <comment>
+            Don't translate: 'ObjectFile'.
+        </comment>
+    </data>
+
+    <data name="E7117" xml:space="preserve">
+        <value>The assembly {0} was passed multiple times as an input assembly (referenced from {1}).</value>
+        <comment>
+            {0}: the name of an assembly
+            {1}: the path to an assembly
+        </comment>
+    </data>
+
+    <data name="E7118" xml:space="preserve">
+        <value>Failed to AOT compile {0}, the AOT compiler exited with code {1}.</value>
+        <comment>
+            {0}: the path to an assembly
+            {1}: the exit code of a process
+        </comment>
+    </data>
+
+    <data name="E7119" xml:space="preserve">
+        <value>Encountered an assembly reference cycle related to the assembly {0}.</value>
+        <comment>
+            {0}: the path to an assembly
+        </comment>
+    </data>
 </root>

msbuild/Xamarin.MacDev.Tasks/Tasks/AOTCompileTaskBase.cs

@@ -7,6 +7,8 @@
 using Microsoft.Build.Framework;
 using Microsoft.Build.Utilities;
 
+using Mono.Cecil;
+
 using Xamarin.Localization.MSBuild;
 using Xamarin.Utils;
 
@@ -42,11 +44,111 @@ public abstract class AOTCompileTaskBase : XamarinTask {
 		public ITaskItem []? FileWrites { get; set; }
 		#endregion
 
+		class AssemblyInfo {
+			public ITaskItem TaskItem;
+			public bool? IsUpToDate;
+
+			public AssemblyInfo (ITaskItem item)
+			{
+				TaskItem = item;
+			}
+		}
+
+		Dictionary<string, AssemblyInfo> assemblyInfos = new Dictionary<string, AssemblyInfo> (StringComparer.OrdinalIgnoreCase);
+
+		string GetAssemblyName (ITaskItem item)
+		{
+			return Path.GetFileNameWithoutExtension (item.ItemSpec);
+		}
+
+		bool IsUpToDate (ITaskItem assembly)
+		{
+			var assemblyPath = assembly.ItemSpec;
+			var key = GetAssemblyName (assembly);
+			if (assemblyInfos.TryGetValue (key, out var info)) {
+				if (!info.IsUpToDate.HasValue) {
+					Log.LogError (MSBStrings.E7119 /* Encountered an assembly reference cycle related to the assembly {0}. */, assemblyPath);
+					info.IsUpToDate = false;
+					return false;
+				}
+				return info.IsUpToDate.Value;
+			}
+
+			info = new AssemblyInfo (assembly);
+			assemblyInfos [key] = info;
+
+			var finfo = new FileInfo (assemblyPath);
+			if (!finfo.Exists) {
+				Log.LogError (MSBStrings.E0158 /* The file {0} does not exist. */, assemblyPath);
+				info.IsUpToDate = false;
+				return false;
+			}
+
+			// ObjectFile is required
+			var objectFile = assembly.GetMetadata ("ObjectFile");
+			if (string.IsNullOrEmpty (objectFile)) {
+				Log.LogError (MSBStrings.E7116 /* The assembly {0} does not provide an 'ObjectFile' metadata. */, assembly.ItemSpec);
+				info.IsUpToDate = false;
+				return false;
+			}
+			var objectFileInfo = new FileInfo (objectFile);
+			if (!IsUpToDate (finfo, objectFileInfo)) {
+				Log.LogMessage (MessageImportance.Low, "The assembly {0} is not up-to-date with regards to the object file {1}", assemblyPath, objectFile);
+				info.IsUpToDate = false;
+				return false;
+			}
+
+			// LLVMFile is optional
+			var llvmFile = assembly.GetMetadata ("LLVMFile");
+			if (!string.IsNullOrEmpty (llvmFile)) {
+				var llvmFileInfo = new FileInfo (llvmFile);
+				if (!IsUpToDate (finfo, llvmFileInfo)) {
+					Log.LogMessage (MessageImportance.Low, "The assembly {0} is not up-to-date with regards to the llvm file {1}", assemblyPath, llvmFile);
+					info.IsUpToDate = false;
+					return false;
+				}
+			}
+
+			// We know now the assembly itself is up-to-date, but what about every referenced assembly?
+			// This assembly must be AOT-compiled again if any referenced assembly has changed as well.
+			using var ad = AssemblyDefinition.ReadAssembly (assembly.ItemSpec, new ReaderParameters { ReadingMode = ReadingMode.Deferred });
+			foreach (var ar in ad.MainModule.AssemblyReferences) {
+				var referencedItems = Assemblies.Where (v => string.Equals (GetAssemblyName (v), ar.Name, StringComparison.OrdinalIgnoreCase)).ToArray ();
+				if (referencedItems.Length == 0) {
+					Log.LogMessage (MessageImportance.Low, $"Ignoring unresolved assembly {ar.Name} (referenced from {assemblyPath}).");
+					continue;
+				} else if (referencedItems.Length > 1) {
+					Log.LogError (MSBStrings.E7117 /* The assembly {0} was passed multiple times as an input assembly (referenced from {1}). */, ar.Name, assemblyPath);
+					info.IsUpToDate = false;
+					return false;
+				}
+				var referencedItem = referencedItems [0];
+				if (!IsUpToDate (referencedItem)) {
+					info.IsUpToDate = false;
+					Log.LogMessage (MessageImportance.Low, "The assembly {0} is not up-to-date with regards to the reference {1}", assemblyPath, ar.Name);
+					return false;
+				}
+			}
+
+			Log.LogMessage (MessageImportance.Low, $"The AOT-compiled code for {assemblyPath} is up-to-date.");
+			info.IsUpToDate = true;
+			return true;
+		}
+
+		bool IsUpToDate (FileInfo input, FileInfo output)
+		{
+			if (!output.Exists)
+				return false;
+			return input.LastWriteTimeUtc <= output.LastWriteTimeUtc;
+		}
+
 		public override bool Execute ()
 		{
 			var inputs = new List<string> (Assemblies.Length);
 			for (var i = 0; i < Assemblies.Length; i++) {
-				inputs.Add (Path.GetFullPath (Assemblies [i].ItemSpec));
+				var input = Path.GetFullPath (Assemblies [i].ItemSpec);
+				inputs.Add (input);
+				Assemblies [i].SetMetadata ("Input", input);
 			}
 
 			// All the assemblies to AOT must be in the same directory
@@ -64,6 +166,13 @@ public override bool Execute ()
 				InputDirectory = assemblyDirectories [0];
 			}
 
+			// Figure out which assemblies need to be aot'ed, and which are up-to-date.
+			var assembliesToAOT = Assemblies.Where (asm => !IsUpToDate (asm)).ToArray ();
+			if (assembliesToAOT.Length == 0) {
+				Log.LogMessage (MessageImportance.Low, $"All the AOT-compiled code is up-to-date.");
+				return !Log.HasLoggedErrors;
+			}
+
 			Directory.CreateDirectory (OutputDirectory);
 
 			var aotAssemblyFiles = new List<ITaskItem> ();
@@ -74,14 +183,14 @@ public override bool Execute ()
 
 			var globalAotArguments = AotArguments?.Select (v => v.ItemSpec).ToList ();
 			var listOfArguments = new List<(IList<string> Arguments, string Input)> ();
-			for (var i = 0; i < Assemblies.Length; i++) {
-				var asm = Assemblies [i];
-				var input = inputs [i];
-				var arch = Assemblies [i].GetMetadata ("Arch");
-				var aotArguments = Assemblies [i].GetMetadata ("Arguments");
-				var processArguments = Assemblies [i].GetMetadata ("ProcessArguments");
-				var aotData = Assemblies [i].GetMetadata ("AOTData");
-				var aotAssembly = Assemblies [i].GetMetadata ("AOTAssembly");
+			for (var i = 0; i < assembliesToAOT.Length; i++) {
+				var asm = assembliesToAOT [i];
+				var input = asm.GetMetadata ("Input");
+				var arch = asm.GetMetadata ("Arch");
+				var aotArguments = asm.GetMetadata ("Arguments");
+				var processArguments = asm.GetMetadata ("ProcessArguments");
+				var aotData = asm.GetMetadata ("AOTData");
+				var aotAssembly = asm.GetMetadata ("AOTAssembly");
 
 				var aotAssemblyItem = new TaskItem (aotAssembly);
 				aotAssemblyItem.SetMetadata ("Arguments", "-Xlinker -rpath -Xlinker @executable_path/ -Qunused-arguments -x assembler -D DEBUG");
@@ -110,7 +219,7 @@ public override bool Execute ()
 				ExecuteAsync (AOTCompilerPath, arg.Arguments, environment: environment, sdkDevPath: SdkDevPath, showErrorIfFailure: false /* we show our own error below */)
 					.ContinueWith ((v) => {
 						if (v.Result.ExitCode != 0)
-							Log.LogError ("Failed to AOT compile {0}, the AOT compiler exited with code {1}", Path.GetFileName (arg.Input), v.Result.ExitCode);
+							Log.LogError (MSBStrings.E7118 /* Failed to AOT compile {0}, the AOT compiler exited with code {1} */, Path.GetFileName (arg.Input), v.Result.ExitCode);
 
 						return System.Threading.Tasks.Task.FromResult<Execution> (v.Result);
 					})
@@ -122,8 +231,8 @@ public override bool Execute ()
 
 			// For Windows support it's necessary to have the files we're going to create as an Output parameter, so that the files are
 			// created on the windows side too, which makes the Inputs/Outputs logic work properly when working from Windows.
-			var objectFiles = Assemblies.Select (v => v.GetMetadata ("ObjectFile")).Where (v => !string.IsNullOrEmpty (v));
-			var llvmFiles = Assemblies.Select (v => v.GetMetadata ("LLVMFile")).Where (v => !string.IsNullOrEmpty (v));
+			var objectFiles = assembliesToAOT.Select (v => v.GetMetadata ("ObjectFile")).Where (v => !string.IsNullOrEmpty (v));
+			var llvmFiles = assembliesToAOT.Select (v => v.GetMetadata ("LLVMFile")).Where (v => !string.IsNullOrEmpty (v));
 			FileWrites = objectFiles.Union (llvmFiles).Select (v => new TaskItem (v)).ToArray ();
 
 			return !Log.HasLoggedErrors;

tests/dotnet/RebuildTestAppWithLibraryReference/AppDelegate.cs

@@ -0,0 +1,18 @@
+using System;
+using System.Runtime.InteropServices;
+
+using Foundation;
+
+namespace MySimpleApp {
+	public class Program {
+		static int Main (string [] args)
+		{
+			GC.KeepAlive (typeof (NSObject)); // prevent linking away the platform assembly
+
+			Console.WriteLine (Environment.GetEnvironmentVariable ("MAGIC_WORD"));
+			Console.WriteLine (Library.Class.SomeFunction ());
+
+			return args.Length;
+		}
+	}
+}

tests/dotnet/RebuildTestAppWithLibraryReference/Library/Library.cs

@@ -0,0 +1,15 @@
+using System;
+using System.Runtime.InteropServices;
+
+namespace Library {
+	public class Class {
+		public static string SomeFunction ()
+		{
+#if FIRSTBUILD
+			return "FIRSTBUILD";
+#elif SECONDBUILD
+			return "SECONDBUILD";
+#endif
+		}
+	}
+}

tests/dotnet/RebuildTestAppWithLibraryReference/Library/MacCatalyst/Library.csproj

@@ -0,0 +1,7 @@
+<?xml version="1.0" encoding="utf-8"?>
+<Project Sdk="Microsoft.NET.Sdk">
+	<PropertyGroup>
+		<TargetFrameworks>net$(BundledNETCoreAppTargetFrameworkVersion)</TargetFrameworks>
+	</PropertyGroup>
+	<Import Project="..\shared.csproj" />
+</Project>

tests/dotnet/RebuildTestAppWithLibraryReference/Library/MacCatalyst/Makefile

@@ -0,0 +1 @@
+include ../shared.mk

tests/dotnet/RebuildTestAppWithLibraryReference/Library/Makefile

@@ -0,0 +1,2 @@
+TOP=../../../..
+include $(TOP)/tests/common/shared-dotnet-test.mk

tests/dotnet/RebuildTestAppWithLibraryReference/Library/iOS/Library.csproj

@@ -0,0 +1,7 @@
+<?xml version="1.0" encoding="utf-8"?>
+<Project Sdk="Microsoft.NET.Sdk">
+	<PropertyGroup>
+		<TargetFrameworks>net$(BundledNETCoreAppTargetFrameworkVersion)</TargetFrameworks>
+	</PropertyGroup>
+	<Import Project="..\shared.csproj" />
+</Project>

tests/dotnet/RebuildTestAppWithLibraryReference/Library/iOS/Makefile

@@ -0,0 +1 @@
+include ../shared.mk

tests/dotnet/RebuildTestAppWithLibraryReference/Library/macOS/Library.csproj

@@ -0,0 +1,7 @@
+<?xml version="1.0" encoding="utf-8"?>
+<Project Sdk="Microsoft.NET.Sdk">
+	<PropertyGroup>
+		<TargetFrameworks>net$(BundledNETCoreAppTargetFrameworkVersion)</TargetFrameworks>
+	</PropertyGroup>
+	<Import Project="..\shared.csproj" />
+</Project>

tests/dotnet/RebuildTestAppWithLibraryReference/Library/macOS/Makefile

@@ -0,0 +1 @@
+include ../shared.mk

tests/dotnet/RebuildTestAppWithLibraryReference/Library/shared.csproj

@@ -0,0 +1,12 @@
+<?xml version="1.0" encoding="utf-8"?>
+<Project>
+	<PropertyGroup>
+		<OutputType>Library</OutputType>
+		<DefineConstants Condition="'$(BuildCounter)' == 'First'">$(DefineConstants);FIRSTBUILD</DefineConstants>
+		<DefineConstants Condition="'$(BuildCounter)' == 'Second'">$(DefineConstants);SECONDBUILD</DefineConstants>
+	</PropertyGroup>
+
+	<ItemGroup>
+		<Compile Include="../*.cs" />
+	</ItemGroup>
+</Project>

tests/dotnet/RebuildTestAppWithLibraryReference/Library/shared.mk

@@ -0,0 +1,2 @@
+TOP=../../../../..
+include $(TOP)/tests/common/shared-dotnet.mk

tests/dotnet/RebuildTestAppWithLibraryReference/Library/tvOS/Library.csproj

@@ -0,0 +1,7 @@
+<?xml version="1.0" encoding="utf-8"?>
+<Project Sdk="Microsoft.NET.Sdk">
+	<PropertyGroup>
+		<TargetFrameworks>net$(BundledNETCoreAppTargetFrameworkVersion)</TargetFrameworks>
+	</PropertyGroup>
+	<Import Project="..\shared.csproj" />
+</Project>

tests/dotnet/RebuildTestAppWithLibraryReference/Library/tvOS/Makefile

@@ -0,0 +1 @@
+include ../shared.mk

tests/dotnet/RebuildTestAppWithLibraryReference/MacCatalyst/Makefile

@@ -0,0 +1 @@
+include ../shared.mk

tests/dotnet/RebuildTestAppWithLibraryReference/MacCatalyst/RebuildTestAppWithLibraryReference.csproj

@@ -0,0 +1,7 @@
+<?xml version="1.0" encoding="utf-8"?>
+<Project Sdk="Microsoft.NET.Sdk">
+	<PropertyGroup>
+		<TargetFramework>net$(BundledNETCoreAppTargetFrameworkVersion)-maccatalyst</TargetFramework>
+	</PropertyGroup>
+	<Import Project="..\shared.csproj" />
+</Project>

tests/dotnet/RebuildTestAppWithLibraryReference/Makefile

@@ -0,0 +1,2 @@
+TOP=../../..
+include $(TOP)/tests/common/shared-dotnet-test.mk

tests/dotnet/RebuildTestAppWithLibraryReference/iOS/Makefile

@@ -0,0 +1 @@
+include ../shared.mk

tests/dotnet/RebuildTestAppWithLibraryReference/iOS/RebuildTestAppWithLibraryReference.csproj

@@ -0,0 +1,7 @@
+<?xml version="1.0" encoding="utf-8"?>
+<Project Sdk="Microsoft.NET.Sdk">
+	<PropertyGroup>
+		<TargetFramework>net$(BundledNETCoreAppTargetFrameworkVersion)-ios</TargetFramework>
+	</PropertyGroup>
+	<Import Project="..\shared.csproj" />
+</Project>

tests/dotnet/RebuildTestAppWithLibraryReference/macOS/Makefile

@@ -0,0 +1 @@
+include ../shared.mk

tests/dotnet/RebuildTestAppWithLibraryReference/macOS/RebuildTestAppWithLibraryReference.csproj

@@ -0,0 +1,7 @@
+<?xml version="1.0" encoding="utf-8"?>
+<Project Sdk="Microsoft.NET.Sdk">
+	<PropertyGroup>
+		<TargetFramework>net$(BundledNETCoreAppTargetFrameworkVersion)-macos</TargetFramework>
+	</PropertyGroup>
+	<Import Project="..\shared.csproj" />
+</Project>

tests/dotnet/RebuildTestAppWithLibraryReference/shared.csproj

@@ -0,0 +1,19 @@
+<?xml version="1.0" encoding="utf-8"?>
+<Project>
+	<PropertyGroup>
+		<OutputType>Exe</OutputType>
+
+		<ApplicationTitle>RebuildTestAppWithLibraryReference</ApplicationTitle>
+		<ApplicationId>com.xamarin.rebuildtestappwithlibraryreference</ApplicationId>
+
+		<ExcludeTouchUnitReference>true</ExcludeTouchUnitReference>
+		<ExcludeNUnitLiteReference>true</ExcludeNUnitLiteReference>
+	</PropertyGroup>
+
+	<Import Project="../../common/shared-dotnet.csproj" />
+
+	<ItemGroup>
+		<Compile Include="../*.cs" />
+		<ProjectReference Include="../Library/$(_PlatformName)/Library.csproj" />
+	</ItemGroup>
+</Project>

tests/dotnet/RebuildTestAppWithLibraryReference/shared.mk

@@ -0,0 +1,2 @@
+TOP=../../../..
+include $(TOP)/tests/common/shared-dotnet.mk

tests/dotnet/RebuildTestAppWithLibraryReference/tvOS/Makefile

@@ -0,0 +1 @@
+include ../shared.mk

tests/dotnet/RebuildTestAppWithLibraryReference/tvOS/RebuildTestAppWithLibraryReference.csproj

@@ -0,0 +1,7 @@
+<?xml version="1.0" encoding="utf-8"?>
+<Project Sdk="Microsoft.NET.Sdk">
+	<PropertyGroup>
+		<TargetFramework>net$(BundledNETCoreAppTargetFrameworkVersion)-tvos</TargetFramework>
+	</PropertyGroup>
+	<Import Project="..\shared.csproj" />
+</Project>