From 8b56ee1f6cea4fbf33dc86ecc6d864f2614584b9 Mon Sep 17 00:00:00 2001
From: Rolf Bjarne Kvinge <rolf@xamarin.com>
Date: Tue, 23 Jun 2026 17:31:43 +0200
Subject: [PATCH] [dotnet] R2R-compile only System.Private.CoreLib for Debug
 CoreCLR arm64 builds

Only apply the PublishReadyToRunCompositeRoots optimization for arm64
RuntimeIdentifiers, since it broke x64 builds.

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
---
 dotnet/targets/Microsoft.Sdk.R2R.targets | 9 +++++++++
 1 file changed, 9 insertions(+)

diff --git a/dotnet/targets/Microsoft.Sdk.R2R.targets b/dotnet/targets/Microsoft.Sdk.R2R.targets
index 0c454db1840b..cf58b3dec260 100644
--- a/dotnet/targets/Microsoft.Sdk.R2R.targets
+++ b/dotnet/targets/Microsoft.Sdk.R2R.targets
@@ -86,6 +86,7 @@
 				Condition="'%(_ResolvedAssembliesToPublish.NuGetPackageId)' != ''" />
 			<_UserAssemblies Include="@(_ResolvedAssembliesToPublish)" Exclude="@(_NonUserAssemblies)" />
 			<PublishReadyToRunExclude Include="@(_UserAssemblies -> '%(Filename)%(Extension)')" />
+			<PublishReadyToRunCompositeRoots Condition="$(RuntimeIdentifier.EndsWith('-arm64'))" Include="System.Private.CoreLib.dll" KeepDuplicates="false" />
 		</ItemGroup>
 
 		<!-- Hash the R2R input assemblies so we can detect when the set actually changes -->
@@ -119,6 +120,14 @@
 			Condition="Exists('%(_ReadyToRunCompileList.OutputR2RImage)')" />
 	</Target>
 
+	<Target Name="_DedupUnrootedReadyToRunPublish"
+			Condition="@(PublishReadyToRunCompositeRoots->Count()) != 0"
+			AfterTargets="_PrepareForReadyToRunCompilation">
+		<ItemGroup>
+			<ResolvedFileToPublish Remove="@(_ReadyToRunCompositeUnrootedBuildInput)" />
+		</ItemGroup>
+	</Target>
+
 	<!--
 		The following section creates either a .dylib or a .framework for each
 		ReadyToRun output (which is an object file that must be linked into a dynamic library).