From e6f5daac2bbe06e660c7fc62c07e12e2437e05d5 Mon Sep 17 00:00:00 2001
From: Jeremy Koritzinsky <jekoritz@microsoft.com>
Date: Wed, 2 Sep 2026 10:30:59 -0700
Subject: [PATCH 1/9] Use project references for shared framework packs

Derive managed shared framework and generator inputs from NetCoreAppLibrary.props, and rebuild native library inputs through build-native.proj before packaging.

Co-authored-by: Copilot App <223556219+Copilot@users.noreply.github.com>

Copilot-Session: a02d8ce4-72ef-40df-b3d2-8bea5d31d7a4
---
 eng/Subsets.props                             |  9 ++-
 eng/liveBuilds.targets                        | 29 +++++++--
 .../Microsoft.NETCore.App.Ref.sfxproj         | 59 +++++++++++++++++--
 ...rosoft.NETCore.App.Runtime.CoreCLR.sfxproj | 19 ++++--
 .../Microsoft.NETCore.App.Runtime.props       | 30 +++++++++-
 .../NetCoreAppLibraryProjectReferences.props  | 47 +++++++++++++++
 src/libraries/sfx-gen.proj                    | 13 +---
 src/libraries/sfx-src.proj                    | 14 +----
 8 files changed, 180 insertions(+), 40 deletions(-)
 create mode 100644 src/libraries/NetCoreAppLibraryProjectReferences.props

diff --git a/eng/Subsets.props b/eng/Subsets.props
index d7b4c953cd9f73..54f84aaea37ff3 100644
--- a/eng/Subsets.props
+++ b/eng/Subsets.props
@@ -635,7 +635,10 @@
 
   <!-- Libraries sets -->
   <ItemGroup Condition="$(_subset.Contains('+libs.native+'))">
-    <ProjectToBuild Include="$(SharedNativeRoot)libs\build-native.proj" Category="libs" />
+    <ProjectToBuild Include="$(SharedNativeRoot)libs\build-native.proj"
+                    AdditionalProperties="LibrariesRuntimeFlavor=$(RuntimeFlavor);RuntimeFlavor=$(RuntimeFlavor)"
+                    GlobalPropertiesToRemove="RuntimeIdentifier;TargetFramework"
+                    Category="libs" />
   </ItemGroup>
 
   <ItemGroup Condition="$(_subset.Contains('+libs.sfx+'))">
@@ -764,7 +767,9 @@
           </ItemGroup>
           <ItemGroup>
             <SharedFrameworkProjectToBuild Condition="'$(_BuildBundle)' == 'true'" Include="$(InstallerProjectRoot)pkg\sfx\bundle\Microsoft.NETCore.App.Bundle.bundleproj" />
-            <ProjectToBuild Include="@(SharedFrameworkProjectToBuild)" Category="packs" />
+            <ProjectToBuild Include="@(SharedFrameworkProjectToBuild)"
+                            AdditionalProperties="%(SharedFrameworkProjectToBuild.AdditionalProperties);LibrariesRuntimeFlavor=$(RuntimeFlavor)"
+                            Category="packs" />
           </ItemGroup>
         </Otherwise>
       </Choose>
diff --git a/eng/liveBuilds.targets b/eng/liveBuilds.targets
index e494ca933bdbea..0e650e92fffe8e 100644
--- a/eng/liveBuilds.targets
+++ b/eng/liveBuilds.targets
@@ -166,16 +166,25 @@
     Ensure artifacts exist for the more advanced paths. If the configuration is '*', don't emit
     these errors: it isn't a local dev scenario.
   -->
-  <Target Name="EnsureLocalOSGroupConfigurationArchitectureSpecificArtifactsExist"
+  <Target Name="EnsureLocalLibrariesRuntimeArtifactsExist"
           Condition="'$(LibrariesTargetOSConfigurationArchitecture)' != '*'">
     <Error Condition="!Exists('$(LibrariesSharedFrameworkBinArtifactsPath)')"
            Text="The 'libs' subset must be built before building this project. Missing artifacts: $(LibrariesSharedFrameworkBinArtifactsPath). Configuration: '$(LibrariesConfiguration)'. To use a different configuration, specify the 'LibrariesConfiguration' property." />
     <Error Condition="'$(IncludeOOBLibraries)' == 'true' and !Exists('$(LibrariesAllBinArtifactsPath)')"
            Text="The 'libs' subset must be built before building this project. Missing artifacts: $(LibrariesAllBinArtifactsPath). Configuration: '$(LibrariesConfiguration)'. To use a different configuration, specify the 'LibrariesConfiguration' property." />
+  </Target>
+
+  <Target Name="EnsureLocalLibrariesNativeArtifactsExist"
+          Condition="'$(LibrariesTargetOSConfigurationArchitecture)' != '*'">
     <Error Condition="!Exists('$(LibrariesNativeArtifactsPath)')"
            Text="The 'libs' subset must be built before building this project. Missing artifacts: $(LibrariesNativeArtifactsPath). Configuration: '$(LibrariesConfiguration)'. To use a different configuration, specify the 'LibrariesConfiguration' property." />
   </Target>
 
+  <Target Name="EnsureLocalOSGroupConfigurationArchitectureSpecificArtifactsExist"
+          DependsOnTargets="
+            EnsureLocalLibrariesRuntimeArtifactsExist;
+            EnsureLocalLibrariesNativeArtifactsExist" />
+
   <Target Name="ResolveLibrariesRefAssembliesFromLocalBuild"
           DependsOnTargets="EnsureLocalArtifactsExist">
     <ItemGroup>
@@ -185,10 +194,8 @@
     <Error Condition="'@(LibrariesRefAssemblies)' == ''" Text="The 'libs' subset must be built before building this project." />
   </Target>
 
-  <Target Name="ResolveLibrariesRuntimeFilesFromLocalBuild"
-          DependsOnTargets="
-            EnsureLocalArtifactsExist;
-            EnsureLocalOSGroupConfigurationArchitectureSpecificArtifactsExist">
+  <Target Name="ResolveLibrariesManagedRuntimeFilesFromLocalBuild"
+          DependsOnTargets="EnsureLocalLibrariesRuntimeArtifactsExist">
     <ItemGroup>
       <LibrariesRuntimeFiles Condition="'$(IncludeOOBLibraries)' != 'true'" Include="
         $(LibrariesSharedFrameworkBinArtifactsPath)*.dll;
@@ -198,6 +205,13 @@
         $(LibrariesAllBinArtifactsPath)*.dll;
         $(LibrariesAllBinArtifactsPath)*.pdb"
         IsNative="" />
+    </ItemGroup>
+    <Error Condition="'@(LibrariesRuntimeFiles)' == ''" Text="The 'libs' subset must be built before building this project." />
+  </Target>
+
+  <Target Name="ResolveLibrariesNativeRuntimeFilesFromLocalBuild"
+          DependsOnTargets="EnsureLocalLibrariesNativeArtifactsExist">
+    <ItemGroup>
       <ExcludeNativeLibrariesRuntimeFiles Condition="'$(IncludeOOBLibraries)' != 'true'"
                                           Include="$(LibrariesNativeArtifactsPath)libSystem.IO.Ports.Native.*" />
 
@@ -373,6 +387,11 @@
     <Error Condition="'@(LibrariesRuntimeFiles)' == ''" Text="The 'libs' subset must be built before building this project." />
   </Target>
 
+  <Target Name="ResolveLibrariesRuntimeFilesFromLocalBuild"
+          DependsOnTargets="
+            ResolveLibrariesManagedRuntimeFilesFromLocalBuild;
+            ResolveLibrariesNativeRuntimeFilesFromLocalBuild" />
+
   <Target Name="ResolveLibrariesFromLocalBuild"
           DependsOnTargets="
             ResolveLibrariesRefAssembliesFromLocalBuild;
diff --git a/src/installer/pkg/sfx/Microsoft.NETCore.App/Microsoft.NETCore.App.Ref.sfxproj b/src/installer/pkg/sfx/Microsoft.NETCore.App/Microsoft.NETCore.App.Ref.sfxproj
index 0bc53a584574bf..08d669fb6f476b 100644
--- a/src/installer/pkg/sfx/Microsoft.NETCore.App/Microsoft.NETCore.App.Ref.sfxproj
+++ b/src/installer/pkg/sfx/Microsoft.NETCore.App/Microsoft.NETCore.App.Ref.sfxproj
@@ -9,13 +9,62 @@
     <PackageDescription>A set of .NET APIs that are included in the default .NET application model. Contains reference assemblies, documentation, and other design-time assets.</PackageDescription>
   </PropertyGroup>
 
-  <Target Name="AddFrameworkFilesToPackage" DependsOnTargets="ResolveLibrariesFromLocalBuild" BeforeTargets="GetFilesToPackage">
+  <Import Project="$(LibrariesProjectRoot)NetCoreAppLibraryProjectReferences.props" />
+
+  <ItemGroup>
+    <ProjectReference Include="$(LibrariesProjectRoot)sfx-src.proj"
+                      AdditionalProperties="RuntimeFlavor=$(_NetCoreAppLibrariesRuntimeFlavor)"
+                      GlobalPropertiesToRemove="RuntimeIdentifier;TargetFramework"
+                      ReferenceOutputAssembly="false"
+                      SetConfiguration="Configuration=$(LibrariesConfiguration)"
+                      SkipGetTargetFrameworkProperties="true"
+                      OutputItemType="_NetCoreAppLibrarySourceAssembly" />
+    <ProjectReference Include="@(NetCoreAppLibraryGeneratorProject)"
+                      GlobalPropertiesToRemove="RuntimeIdentifier"
+                      ReferenceOutputAssembly="false"
+                      SetConfiguration="Configuration=$(LibrariesConfiguration)" />
+  </ItemGroup>
+
+  <Target Name="GetNetCoreAppRefPackGeneratorFiles"
+          DependsOnTargets="ResolveProjectReferences">
+    <MSBuild Projects="@(NetCoreAppLibraryGeneratorProject)"
+             Targets="GetAnalyzerPackFiles"
+             Properties="Configuration=$(LibrariesConfiguration)"
+             RemoveProperties="RuntimeIdentifier;SetTargetFramework">
+      <Output TaskParameter="TargetOutputs" ItemName="_NetCoreAppRefPackGeneratorFileWithOriginalPath" />
+    </MSBuild>
+
+    <ItemGroup>
+      <_NetCoreAppRefPackGeneratorFile Include="@(_NetCoreAppRefPackGeneratorFileWithOriginalPath)"
+                                       RemoveMetadata="IsSymbol">
+        <TargetPath>$([System.Text.RegularExpressions.Regex]::Replace($([System.Text.RegularExpressions.Regex]::Replace($([System.String]::Copy('%(_NetCoreAppRefPackGeneratorFileWithOriginalPath.PackagePath)').Replace('\', '/')), '^analyzers/dotnet/roslyn[^/]+/', 'analyzers/dotnet/')), '/[^/]+$', '/'))</TargetPath>
+      </_NetCoreAppRefPackGeneratorFile>
+    </ItemGroup>
+  </Target>
+
+  <Target Name="AddFrameworkFilesToPackage"
+          DependsOnTargets="ResolveProjectReferences;GetNetCoreAppRefPackGeneratorFiles"
+          BeforeTargets="GetFilesToPackage">
     <ItemGroup>
-      <ReferencePath Include="@(LibrariesRefAssemblies)" />
+      <_NetCoreAppLibraryPublicSourceAssembly Include="@(_NetCoreAppLibrarySourceAssembly)"
+                                              Condition="'%(_NetCoreAppLibrarySourceAssembly.Extension)' == '.dll' and '%(_NetCoreAppLibrarySourceAssembly.IsPrivateAssembly)' != 'true'" />
+      <_NetCoreAppLibrarySourceAssemblyWithReferenceAssembly Include="@(_NetCoreAppLibraryPublicSourceAssembly)"
+                                                             Condition="'%(_NetCoreAppLibraryPublicSourceAssembly.ReferenceAssembly)' != ''" />
+      <_NetCoreAppLibraryReferenceAssembly Include="@(_NetCoreAppLibrarySourceAssemblyWithReferenceAssembly->Metadata('ReferenceAssembly'))" />
+      <_NetCoreAppLibraryReferenceAssembly Include="@(_NetCoreAppLibraryPublicSourceAssembly)"
+                                           Exclude="@(_NetCoreAppLibrarySourceAssemblyWithReferenceAssembly)" />
+      <_NetCoreAppLibraryReferenceAssemblySymbols Include="@(_NetCoreAppLibraryReferenceAssembly->'%(RootDir)%(Directory)%(Filename).pdb')" />
+      <_NetCoreAppLibraryReferenceAssemblySymbols Remove="@(_NetCoreAppLibraryReferenceAssemblySymbols)"
+                                                  Condition="!Exists('%(_NetCoreAppLibraryReferenceAssemblySymbols.Identity)')" />
+      <ReferencePath Include="@(_NetCoreAppLibraryReferenceAssembly);
+                              @(_NetCoreAppLibraryReferenceAssemblySymbols)" />
       <ReferencePath ReferenceAssembly="%(Identity)" />
-      <DocFilesToPackage Include="$(MicrosoftNetCoreAppRefPackRefDir)%(LibrariesRefAssemblies.FileName).xml" Condition="Exists('$(MicrosoftNetCoreAppRefPackRefDir)%(LibrariesRefAssemblies.FileName).xml')"/>
-      <Analyzer Include="$(MicrosoftNetCoreAppRefPackDir)/analyzers/**/*.*" />
-      <FilesToPackage Include="@(Analyzer)" ExcludeFromValidation="true" TargetPath="analyzers/%(RecursiveDir)" />
+      <_NetCoreAppLibrarySourceAssemblyWithDocumentation Include="@(_NetCoreAppLibraryPublicSourceAssembly)"
+                                                         Condition="'%(_NetCoreAppLibraryPublicSourceAssembly.DocFileItem)' != '' and Exists('%(_NetCoreAppLibraryPublicSourceAssembly.DocFileItem)')" />
+      <DocFilesToPackage Include="@(_NetCoreAppLibrarySourceAssemblyWithDocumentation->Metadata('DocFileItem'))" />
+      <FilesToPackage Include="@(_NetCoreAppRefPackGeneratorFile)"
+                      ExcludeFromValidation="true"
+                      TargetPath="%(_NetCoreAppRefPackGeneratorFile.TargetPath)" />
     </ItemGroup>
   </Target>
 </Project>
diff --git a/src/installer/pkg/sfx/Microsoft.NETCore.App/Microsoft.NETCore.App.Runtime.CoreCLR.sfxproj b/src/installer/pkg/sfx/Microsoft.NETCore.App/Microsoft.NETCore.App.Runtime.CoreCLR.sfxproj
index 55cfb97672da4e..ccfe3b6c5dfaf2 100644
--- a/src/installer/pkg/sfx/Microsoft.NETCore.App/Microsoft.NETCore.App.Runtime.CoreCLR.sfxproj
+++ b/src/installer/pkg/sfx/Microsoft.NETCore.App/Microsoft.NETCore.App.Runtime.CoreCLR.sfxproj
@@ -73,14 +73,16 @@
   <PropertyGroup Condition="'$(TargetsBrowser)' == 'true' and '$(RuntimeFlavor)' == 'CoreCLR'">
     <WasmEnableFrameworkR2R Condition="'$(WasmEnableFrameworkR2R)' == ''">true</WasmEnableFrameworkR2R>
     <_WasmFrameworkR2RDir>$([MSBuild]::NormalizeDirectory('$(IntermediateOutputPath)', 'framework-r2r'))</_WasmFrameworkR2RDir>
+    <_WasmFrameworkR2RResponseFile>$(_WasmFrameworkR2RDir)references.rsp</_WasmFrameworkR2RResponseFile>
   </PropertyGroup>
 
   <Target Name="_ComputeBrowserFrameworkR2RInputs"
           Condition="'$(WasmEnableFrameworkR2R)' == 'true'"
-          DependsOnTargets="ResolveLibrariesFromLocalBuild;ResolveRuntimeFilesFromLocalBuild">
+          DependsOnTargets="ResolveProjectReferences;ResolveRuntimeFilesFromLocalBuild">
     <ItemGroup>
-      <_WasmFrameworkR2RInput Include="$(LibrariesSharedFrameworkBinArtifactsPath)*.dll"
-                              Exclude="$(LibrariesSharedFrameworkBinArtifactsPath)*.resources.dll" />
+      <_WasmFrameworkR2RInput Include="@(_NetCoreAppLibrarySourceAssembly)"
+                              Condition="'%(_NetCoreAppLibrarySourceAssembly.Extension)' == '.dll' and '%(_NetCoreAppLibrarySourceAssembly.Filename)' != 'System.Private.CoreLib'" />
+      <_WasmFrameworkR2RReference Include="@(_WasmFrameworkR2RInput)" />
       <!-- Optional subset filter for bring-up: keep only assemblies named in WasmFrameworkR2RSubset. -->
       <_WasmFrameworkR2RInput Remove="@(_WasmFrameworkR2RInput)"
                               Condition="'$(WasmFrameworkR2RSubset)' != '' and !$([System.String]::Copy(';$(WasmFrameworkR2RSubset);').Contains(';%(FileName);'))" />
@@ -89,7 +91,7 @@
       </_WasmFrameworkR2RInput>
       <!-- Full crossgen -r closure so a change to ANY referenced framework assembly re-runs crossgen,
            even when only a WasmFrameworkR2RSubset is being compiled. -->
-      <_WasmFrameworkR2RReference Include="$(LibrariesSharedFrameworkBinArtifactsPath)*.dll" />
+      <_WasmFrameworkR2RReferenceArgument Include="@(_WasmFrameworkR2RReference->'-r:&quot;%(Identity)&quot;')" />
     </ItemGroup>
     <PropertyGroup>
       <_WasmCoreLibIL Condition="Exists('$(CoreCLRArtifactsPath)System.Private.CoreLib.dll')">$(CoreCLRArtifactsPath)System.Private.CoreLib.dll</_WasmCoreLibIL>
@@ -104,6 +106,10 @@
           Inputs="@(_WasmFrameworkR2RInput);@(_WasmFrameworkR2RReference);$(_WasmCoreLibIL);$(_WasmCrossgen2Exe)"
           Outputs="@(_WasmFrameworkR2RInput->'%(OutputWasm)')">
     <MakeDir Directories="$(_WasmFrameworkR2RDir)" />
+    <WriteLinesToFile File="$(_WasmFrameworkR2RResponseFile)"
+                      Lines="@(_WasmFrameworkR2RReferenceArgument)"
+                      Overwrite="true"
+                      WriteOnlyWhenDifferent="true" />
     <Error Condition="!Exists('$(_WasmCrossgen2Exe)')"
            Text="WasmEnableFrameworkR2R is true but crossgen2 was not found at '$(_WasmCrossgen2Exe)'. Build the crossgen2 pack or set WasmEnableFrameworkR2R=false." />
     <Error Condition="'$(_WasmCoreLibIL)' == ''"
@@ -111,7 +117,10 @@
     <Message Importance="High" Text="Crossgen R2R (wasm): %(_WasmFrameworkR2RInput.FileName)" />
     <!-- opt-cross-module:* enables cross-module inlining/optimization across the whole shared framework
          (the -r closure); still one R2R image per assembly (non-composite). -->
-    <Exec Command="&quot;$(_WasmCrossgen2Exe)&quot; -o:&quot;%(_WasmFrameworkR2RInput.OutputWasm)&quot; -r:&quot;$(LibrariesSharedFrameworkBinArtifactsPath)*.dll&quot; -r:&quot;$(_WasmCoreLibIL)&quot; &quot;--opt-cross-module:*&quot; --targetarch:$(TargetArchitecture) --targetos:$(TargetOS) --obj-format:wasm --codegenopt:JitWasmNyiToR2RUnsupported=1 --codegenopt:JitWasmSimdNyiToR2RUnsupported=1 -O &quot;%(_WasmFrameworkR2RInput.FullPath)&quot;" />
+    <Exec Command="&quot;$(_WasmCrossgen2Exe)&quot; -o:&quot;%(_WasmFrameworkR2RInput.OutputWasm)&quot; @&quot;$(_WasmFrameworkR2RResponseFile)&quot; -r:&quot;$(_WasmCoreLibIL)&quot; &quot;--opt-cross-module:*&quot; --targetarch:$(TargetArchitecture) --targetos:$(TargetOS) --obj-format:wasm --codegenopt:JitWasmNyiToR2RUnsupported=1 --codegenopt:JitWasmSimdNyiToR2RUnsupported=1 -O &quot;%(_WasmFrameworkR2RInput.FullPath)&quot;" />
+    <ItemGroup>
+      <FileWrites Include="$(_WasmFrameworkR2RResponseFile)" />
+    </ItemGroup>
   </Target>
 
   <!-- No Inputs/Outputs so images are packed even when crossgen was incrementally skipped. native/r2r is a
diff --git a/src/installer/pkg/sfx/Microsoft.NETCore.App/Microsoft.NETCore.App.Runtime.props b/src/installer/pkg/sfx/Microsoft.NETCore.App/Microsoft.NETCore.App.Runtime.props
index db017617784bac..2449e70a676069 100644
--- a/src/installer/pkg/sfx/Microsoft.NETCore.App/Microsoft.NETCore.App.Runtime.props
+++ b/src/installer/pkg/sfx/Microsoft.NETCore.App/Microsoft.NETCore.App.Runtime.props
@@ -1,4 +1,22 @@
 <Project>
+  <Import Project="$(LibrariesProjectRoot)NetCoreAppLibraryProjectReferences.props" />
+
+  <ItemGroup>
+    <ProjectReference Include="$(SharedNativeRoot)libs\build-native.proj"
+                      AdditionalProperties="RuntimeFlavor=$(_NetCoreAppLibrariesRuntimeFlavor)"
+                      GlobalPropertiesToRemove="RuntimeIdentifier;TargetFramework"
+                      ReferenceOutputAssembly="false"
+                      SetConfiguration="Configuration=$(LibrariesConfiguration)"
+                      SkipGetTargetFrameworkProperties="true" />
+    <ProjectReference Include="$(LibrariesProjectRoot)sfx-src.proj"
+                      AdditionalProperties="RuntimeFlavor=$(_NetCoreAppLibrariesRuntimeFlavor)"
+                      GlobalPropertiesToRemove="RuntimeIdentifier;TargetFramework"
+                      ReferenceOutputAssembly="false"
+                      SetConfiguration="Configuration=$(LibrariesConfiguration)"
+                      SkipGetTargetFrameworkProperties="true"
+                      OutputItemType="_NetCoreAppLibrarySourceAssembly" />
+  </ItemGroup>
+
   <PropertyGroup>
     <IncludeFallbacksInDepsFile>true</IncludeFallbacksInDepsFile>
     <GetSharedFrameworkFilesForReadyToRunDependsOn>
@@ -44,10 +62,18 @@
     </ItemGroup>
   </Target>
 
-  <Target Name="AddFrameworkFilesToPackage" DependsOnTargets="ResolveLibrariesFromLocalBuild">
+  <Target Name="AddFrameworkFilesToPackage"
+          DependsOnTargets="ResolveProjectReferences;ResolveLibrariesNativeRuntimeFilesFromLocalBuild">
     <ItemGroup>
+      <_NetCoreAppLibraryRuntimeAssembly Include="@(_NetCoreAppLibrarySourceAssembly)"
+                                         Condition="'%(_NetCoreAppLibrarySourceAssembly.Extension)' == '.dll' and '%(_NetCoreAppLibrarySourceAssembly.Filename)' != 'System.Private.CoreLib'" />
+      <_NetCoreAppLibraryRuntimeAssemblySymbols Include="@(_NetCoreAppLibraryRuntimeAssembly->'%(RootDir)%(Directory)%(Filename).pdb')" />
+      <_NetCoreAppLibraryRuntimeAssemblySymbols Remove="@(_NetCoreAppLibraryRuntimeAssemblySymbols)"
+                                                Condition="!Exists('%(_NetCoreAppLibraryRuntimeAssemblySymbols.Identity)')" />
+      <ReferenceCopyLocalPaths Include="@(_NetCoreAppLibraryRuntimeAssembly);
+                                        @(_NetCoreAppLibraryRuntimeAssemblySymbols)" />
       <ReferenceCopyLocalPaths Include="@(LibrariesRuntimeFiles)"
-        Condition="'%(LibrariesRuntimeFiles.Extension)' != '$(StaticLibSuffix)' or '$(IncludeStaticLibrariesInPack)' == 'true'">
+                               Condition="'%(LibrariesRuntimeFiles.Extension)' != '$(StaticLibSuffix)' or '$(IncludeStaticLibrariesInPack)' == 'true'">
         <TargetPath Condition="'%(LibrariesRuntimeFiles.NativeSubDirectory)' != ''">runtimes/$(RuntimeIdentifier)/native/%(LibrariesRuntimeFiles.NativeSubDirectory)%(RecursiveDir)</TargetPath>
       </ReferenceCopyLocalPaths>
     </ItemGroup>
diff --git a/src/libraries/NetCoreAppLibraryProjectReferences.props b/src/libraries/NetCoreAppLibraryProjectReferences.props
new file mode 100644
index 00000000000000..3e10e1020db71a
--- /dev/null
+++ b/src/libraries/NetCoreAppLibraryProjectReferences.props
@@ -0,0 +1,47 @@
+<Project>
+
+  <PropertyGroup>
+    <_NetCoreAppLibrariesRuntimeFlavor>$([MSBuild]::ValueOrDefault('$(LibrariesRuntimeFlavor)', '$(RuntimeFlavor)'))</_NetCoreAppLibrariesRuntimeFlavor>
+  </PropertyGroup>
+
+  <ItemGroup>
+    <_NetCoreAppLibrarySourceProject Include="$(LibrariesProjectRoot)*\src\*.*proj"
+                                     Exclude="@(ProjectExclusions);
+                                              $(LibrariesProjectRoot)*\src\*.shproj" />
+    <_NonNetCoreAppLibrarySourceProject Include="@(_NetCoreAppLibrarySourceProject)"
+                                        Exclude="@(NetCoreAppLibrary->'$(LibrariesProjectRoot)%(Identity)\src\%(Identity).csproj');
+                                                 $(LibrariesProjectRoot)Microsoft.VisualBasic.Core\src\Microsoft.VisualBasic.Core.vbproj" />
+
+    <_NetCoreAppLibraryShimProject Include="$(LibrariesProjectRoot)shims\*\src\*.csproj"
+                                   OriginalIdentity="%(Identity)" />
+    <_NetCoreAppLibraryShimProjectName Include="@(_NetCoreAppLibraryShimProject->Metadata('Filename'))" />
+    <_NonNetCoreAppLibraryShimProjectName Include="@(_NetCoreAppLibraryShimProjectName)"
+                                          Exclude="@(NetCoreAppLibrary)" />
+    <_IncludedNetCoreAppLibraryShimProjectName Include="@(_NetCoreAppLibraryShimProjectName)"
+                                               Exclude="@(_NonNetCoreAppLibraryShimProjectName)" />
+
+    <NetCoreAppLibrarySourceProject Include="@(_NetCoreAppLibrarySourceProject);
+                                             $(CoreLibProject);
+                                             @(_IncludedNetCoreAppLibraryShimProjectName->Metadata('OriginalIdentity'))"
+                                    Exclude="@(_NonNetCoreAppLibrarySourceProject)" />
+  </ItemGroup>
+
+  <ItemGroup>
+    <_NetCoreAppLibraryGeneratorProject Include="$(LibrariesProjectRoot)*\gen\**\*.*proj"
+                                        Exclude="@(ProjectExclusions)"
+                                        OriginalIdentity="%(Identity)" />
+    <_NetCoreAppLibraryGeneratorProjectName Include="@(_NetCoreAppLibraryGeneratorProject->Metadata('Filename'))" />
+    <_NonNetCoreAppLibraryGeneratorProjectName Include="@(_NetCoreAppLibraryGeneratorProjectName)"
+                                               Exclude="@(NetCoreAppLibraryGenerator)" />
+    <_IncludedNetCoreAppLibraryGeneratorProjectName Include="@(_NetCoreAppLibraryGeneratorProjectName)"
+                                                    Exclude="@(_NonNetCoreAppLibraryGeneratorProjectName)" />
+    <NetCoreAppLibraryGeneratorProject Include="@(_IncludedNetCoreAppLibraryGeneratorProjectName->Metadata('OriginalIdentity'))" />
+  </ItemGroup>
+
+  <Target Name="ValidateNetCoreAppLibraryShimProjects"
+          BeforeTargets="Build"
+          Condition="'@(_NonNetCoreAppLibraryShimProjectName)' != ''">
+    <Error Text="Shared framework shim projects must be listed in NetCoreAppLibrary.props: @(_NonNetCoreAppLibraryShimProjectName, ', ')" />
+  </Target>
+
+</Project>
diff --git a/src/libraries/sfx-gen.proj b/src/libraries/sfx-gen.proj
index 1b3bdf6c104c8d..ac449c9c34fb42 100644
--- a/src/libraries/sfx-gen.proj
+++ b/src/libraries/sfx-gen.proj
@@ -7,17 +7,10 @@
     <NoDefaultSlnGenSolutionFolder>true</NoDefaultSlnGenSolutionFolder>
   </PropertyGroup>
 
-  <!-- Reference all NetCoreAppCurrent shared framework generator projects. -->
+  <Import Project="NetCoreAppLibraryProjectReferences.props" />
+
   <ItemGroup>
-    <AnyProject Include="$(MSBuildThisFileDirectory)*\gen\**\*.*proj"
-                Exclude="@(ProjectExclusions)"
-                OriginalIdentity="%(Identity)" />
-    <AnyProjectWithProjectName Include="@(AnyProject->Metadata('Filename'))" />
-    <NonNetCoreAppProjectWithProjectName Include="@(AnyProjectWithProjectName)"
-                                         Exclude="@(NetCoreAppLibraryGenerator)" />
-    <NetCoreAppProjectWithProjectName Include="@(AnyProjectWithProjectName)"
-                                      Exclude="@(NonNetCoreAppProjectWithProjectName)" />
-    <ProjectReference Include="@(NetCoreAppProjectWithProjectName->Metadata('OriginalIdentity'))" />
+    <ProjectReference Include="@(NetCoreAppLibraryGeneratorProject)" />
   </ItemGroup>
 
 </Project>
diff --git a/src/libraries/sfx-src.proj b/src/libraries/sfx-src.proj
index 8da1f3b306c227..b2823831c9be8d 100644
--- a/src/libraries/sfx-src.proj
+++ b/src/libraries/sfx-src.proj
@@ -7,18 +7,10 @@
     <NoDefaultSlnGenSolutionFolder>true</NoDefaultSlnGenSolutionFolder>
   </PropertyGroup>
 
-  <!-- Reference all NetCoreAppCurrent shared framework src projects. -->
+  <Import Project="NetCoreAppLibraryProjectReferences.props" />
+
   <ItemGroup>
-    <AnyProject Include="$(MSBuildThisFileDirectory)*\src\*.*proj"
-                Exclude="@(ProjectExclusions);
-                         $(MSBuildThisFileDirectory)*\src\*.shproj" />
-    <NonNetCoreAppProject Include="@(AnyProject)"
-                          Exclude="@(NetCoreAppLibrary->'%(Identity)\src\%(Identity).csproj');
-                                   Microsoft.VisualBasic.Core\src\Microsoft.VisualBasic.Core.vbproj" />
-    <ProjectReference Include="@(AnyProject);
-                               $(CoreLibProject);
-                               shims\*\src\*.csproj"
-                      Exclude="@(NonNetCoreAppProject)" />
+    <ProjectReference Include="@(NetCoreAppLibrarySourceProject)" />
   </ItemGroup>
 
 </Project>

From de94a3345437328e124ca8b8bfed4339fff4a8c3 Mon Sep 17 00:00:00 2001
From: Jeremy Koritzinsky <jekoritz@microsoft.com>
Date: Wed, 2 Sep 2026 13:53:02 -0700
Subject: [PATCH 2/9] Limit ref pack generators to netstandard2.0

Avoid building every target framework for generator project references while preserving the existing ref pack analyzer layout.

Co-authored-by: Copilot App <223556219+Copilot@users.noreply.github.com>

Copilot-Session: a02d8ce4-72ef-40df-b3d2-8bea5d31d7a4
---
 .../Microsoft.NETCore.App/Microsoft.NETCore.App.Ref.sfxproj  | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/src/installer/pkg/sfx/Microsoft.NETCore.App/Microsoft.NETCore.App.Ref.sfxproj b/src/installer/pkg/sfx/Microsoft.NETCore.App/Microsoft.NETCore.App.Ref.sfxproj
index 08d669fb6f476b..7b5f2004d4ff7f 100644
--- a/src/installer/pkg/sfx/Microsoft.NETCore.App/Microsoft.NETCore.App.Ref.sfxproj
+++ b/src/installer/pkg/sfx/Microsoft.NETCore.App/Microsoft.NETCore.App.Ref.sfxproj
@@ -22,14 +22,15 @@
     <ProjectReference Include="@(NetCoreAppLibraryGeneratorProject)"
                       GlobalPropertiesToRemove="RuntimeIdentifier"
                       ReferenceOutputAssembly="false"
-                      SetConfiguration="Configuration=$(LibrariesConfiguration)" />
+                      SetConfiguration="Configuration=$(LibrariesConfiguration)"
+                      SetTargetFramework="TargetFramework=netstandard2.0" />
   </ItemGroup>
 
   <Target Name="GetNetCoreAppRefPackGeneratorFiles"
           DependsOnTargets="ResolveProjectReferences">
     <MSBuild Projects="@(NetCoreAppLibraryGeneratorProject)"
              Targets="GetAnalyzerPackFiles"
-             Properties="Configuration=$(LibrariesConfiguration)"
+             Properties="Configuration=$(LibrariesConfiguration);TargetFramework=netstandard2.0"
              RemoveProperties="RuntimeIdentifier;SetTargetFramework">
       <Output TaskParameter="TargetOutputs" ItemName="_NetCoreAppRefPackGeneratorFileWithOriginalPath" />
     </MSBuild>

From 3689d42567d348d20ecd652eb01f11609550cb8d Mon Sep 17 00:00:00 2001
From: Jeremy Koritzinsky <jekoritz@microsoft.com>
Date: Wed, 2 Sep 2026 15:49:33 -0700
Subject: [PATCH 3/9] Package ref generators from project outputs

Use the generator project references to collect analyzer files and preserve no-build and Visual Studio packing from existing outputs.

Co-authored-by: Copilot App <223556219+Copilot@users.noreply.github.com>

Copilot-Session: a02d8ce4-72ef-40df-b3d2-8bea5d31d7a4
---
 .../Microsoft.NETCore.App.Ref.sfxproj         | 48 +++++++++++--------
 1 file changed, 29 insertions(+), 19 deletions(-)

diff --git a/src/installer/pkg/sfx/Microsoft.NETCore.App/Microsoft.NETCore.App.Ref.sfxproj b/src/installer/pkg/sfx/Microsoft.NETCore.App/Microsoft.NETCore.App.Ref.sfxproj
index 7b5f2004d4ff7f..3b820e4beae08d 100644
--- a/src/installer/pkg/sfx/Microsoft.NETCore.App/Microsoft.NETCore.App.Ref.sfxproj
+++ b/src/installer/pkg/sfx/Microsoft.NETCore.App/Microsoft.NETCore.App.Ref.sfxproj
@@ -21,31 +21,37 @@
                       OutputItemType="_NetCoreAppLibrarySourceAssembly" />
     <ProjectReference Include="@(NetCoreAppLibraryGeneratorProject)"
                       GlobalPropertiesToRemove="RuntimeIdentifier"
+                      OutputItemType="_NetCoreAppRefPackGeneratorFile"
                       ReferenceOutputAssembly="false"
                       SetConfiguration="Configuration=$(LibrariesConfiguration)"
-                      SetTargetFramework="TargetFramework=netstandard2.0" />
+                      SetTargetFramework="TargetFramework=netstandard2.0"
+                      Targets="Build;GetAnalyzerPackFiles" />
   </ItemGroup>
 
-  <Target Name="GetNetCoreAppRefPackGeneratorFiles"
-          DependsOnTargets="ResolveProjectReferences">
-    <MSBuild Projects="@(NetCoreAppLibraryGeneratorProject)"
-             Targets="GetAnalyzerPackFiles"
-             Properties="Configuration=$(LibrariesConfiguration);TargetFramework=netstandard2.0"
-             RemoveProperties="RuntimeIdentifier;SetTargetFramework">
-      <Output TaskParameter="TargetOutputs" ItemName="_NetCoreAppRefPackGeneratorFileWithOriginalPath" />
-    </MSBuild>
+  <Target Name="AddFrameworkFilesToPackage"
+          DependsOnTargets="ResolveProjectReferences"
+          BeforeTargets="GetFilesToPackage">
+    <ItemGroup Condition="'$(BuildProjectReferences)' != 'true' or '$(BuildingInsideVisualStudio)' == 'true'">
+      <!-- ResolveProjectReferences only calls GetTargetPath during no-build packing and Visual
+           Studio builds. Include related files from the previously populated output directories. -->
+      <_NetCoreAppRefPackGeneratorOutput Include="@(_NetCoreAppRefPackGeneratorFile)" />
+    </ItemGroup>
 
-    <ItemGroup>
-      <_NetCoreAppRefPackGeneratorFile Include="@(_NetCoreAppRefPackGeneratorFileWithOriginalPath)"
-                                       RemoveMetadata="IsSymbol">
-        <TargetPath>$([System.Text.RegularExpressions.Regex]::Replace($([System.Text.RegularExpressions.Regex]::Replace($([System.String]::Copy('%(_NetCoreAppRefPackGeneratorFileWithOriginalPath.PackagePath)').Replace('\', '/')), '^analyzers/dotnet/roslyn[^/]+/', 'analyzers/dotnet/')), '/[^/]+$', '/'))</TargetPath>
-      </_NetCoreAppRefPackGeneratorFile>
+    <Error Condition="'@(_NetCoreAppRefPackGeneratorOutput)' == '' and
+                      ('$(BuildProjectReferences)' != 'true' or '$(BuildingInsideVisualStudio)' == 'true')"
+           Text="The shared framework generators must be built before creating the reference pack." />
+    <Error Condition="'@(_NetCoreAppRefPackGeneratorOutput)' != '' and
+                      !Exists('%(_NetCoreAppRefPackGeneratorOutput.Identity)')"
+           Text="The shared framework generator output '%(_NetCoreAppRefPackGeneratorOutput.Identity)' does not exist." />
+
+    <ItemGroup Condition="'$(BuildProjectReferences)' != 'true' or '$(BuildingInsideVisualStudio)' == 'true'">
+      <_NetCoreAppRefPackGeneratorRelatedFile Include="@(_NetCoreAppRefPackGeneratorOutput)" />
+      <_NetCoreAppRefPackGeneratorRelatedFile Include="@(_NetCoreAppRefPackGeneratorOutput->'%(RootDir)%(Directory)%(Filename).pdb')" />
+      <_NetCoreAppRefPackGeneratorRelatedFile Include="%(_NetCoreAppRefPackGeneratorOutput.RootDir)%(_NetCoreAppRefPackGeneratorOutput.Directory)*\%(_NetCoreAppRefPackGeneratorOutput.Filename).resources.dll" />
+      <_NetCoreAppRefPackGeneratorRelatedFile Remove="@(_NetCoreAppRefPackGeneratorRelatedFile)"
+                                              Condition="!Exists('%(_NetCoreAppRefPackGeneratorRelatedFile.Identity)')" />
     </ItemGroup>
-  </Target>
 
-  <Target Name="AddFrameworkFilesToPackage"
-          DependsOnTargets="ResolveProjectReferences;GetNetCoreAppRefPackGeneratorFiles"
-          BeforeTargets="GetFilesToPackage">
     <ItemGroup>
       <_NetCoreAppLibraryPublicSourceAssembly Include="@(_NetCoreAppLibrarySourceAssembly)"
                                               Condition="'%(_NetCoreAppLibrarySourceAssembly.Extension)' == '.dll' and '%(_NetCoreAppLibrarySourceAssembly.IsPrivateAssembly)' != 'true'" />
@@ -64,8 +70,12 @@
                                                          Condition="'%(_NetCoreAppLibraryPublicSourceAssembly.DocFileItem)' != '' and Exists('%(_NetCoreAppLibraryPublicSourceAssembly.DocFileItem)')" />
       <DocFilesToPackage Include="@(_NetCoreAppLibrarySourceAssemblyWithDocumentation->Metadata('DocFileItem'))" />
       <FilesToPackage Include="@(_NetCoreAppRefPackGeneratorFile)"
+                      Condition="'%(_NetCoreAppRefPackGeneratorFile.PackagePath)' != ''"
+                      ExcludeFromValidation="true"
+                      TargetPath="analyzers/dotnet/cs/%(_NetCoreAppRefPackGeneratorFile.Culture)" />
+      <FilesToPackage Include="@(_NetCoreAppRefPackGeneratorRelatedFile)"
                       ExcludeFromValidation="true"
-                      TargetPath="%(_NetCoreAppRefPackGeneratorFile.TargetPath)" />
+                      TargetPath="analyzers/dotnet/cs/%(_NetCoreAppRefPackGeneratorRelatedFile.RecursiveDir)" />
     </ItemGroup>
   </Target>
 </Project>

From 53d9de87370261636d5d7dbe95a77f157da30fae Mon Sep 17 00:00:00 2001
From: Jeremy Koritzinsky <jekoritz@microsoft.com>
Date: Thu, 3 Sep 2026 10:53:43 -0700
Subject: [PATCH 4/9] Use generator target paths for ref pack

Derive generator assemblies, symbols, and resources uniformly from project reference target paths.

Co-authored-by: Copilot App <223556219+Copilot@users.noreply.github.com>

Copilot-Session: a02d8ce4-72ef-40df-b3d2-8bea5d31d7a4
---
 .../Microsoft.NETCore.App.Ref.sfxproj         | 31 +++----------------
 1 file changed, 5 insertions(+), 26 deletions(-)

diff --git a/src/installer/pkg/sfx/Microsoft.NETCore.App/Microsoft.NETCore.App.Ref.sfxproj b/src/installer/pkg/sfx/Microsoft.NETCore.App/Microsoft.NETCore.App.Ref.sfxproj
index 3b820e4beae08d..75bb3c07743fc6 100644
--- a/src/installer/pkg/sfx/Microsoft.NETCore.App/Microsoft.NETCore.App.Ref.sfxproj
+++ b/src/installer/pkg/sfx/Microsoft.NETCore.App/Microsoft.NETCore.App.Ref.sfxproj
@@ -24,35 +24,18 @@
                       OutputItemType="_NetCoreAppRefPackGeneratorFile"
                       ReferenceOutputAssembly="false"
                       SetConfiguration="Configuration=$(LibrariesConfiguration)"
-                      SetTargetFramework="TargetFramework=netstandard2.0"
-                      Targets="Build;GetAnalyzerPackFiles" />
+                      SetTargetFramework="TargetFramework=netstandard2.0" />
   </ItemGroup>
 
   <Target Name="AddFrameworkFilesToPackage"
           DependsOnTargets="ResolveProjectReferences"
           BeforeTargets="GetFilesToPackage">
-    <ItemGroup Condition="'$(BuildProjectReferences)' != 'true' or '$(BuildingInsideVisualStudio)' == 'true'">
-      <!-- ResolveProjectReferences only calls GetTargetPath during no-build packing and Visual
-           Studio builds. Include related files from the previously populated output directories. -->
-      <_NetCoreAppRefPackGeneratorOutput Include="@(_NetCoreAppRefPackGeneratorFile)" />
-    </ItemGroup>
-
-    <Error Condition="'@(_NetCoreAppRefPackGeneratorOutput)' == '' and
-                      ('$(BuildProjectReferences)' != 'true' or '$(BuildingInsideVisualStudio)' == 'true')"
-           Text="The shared framework generators must be built before creating the reference pack." />
-    <Error Condition="'@(_NetCoreAppRefPackGeneratorOutput)' != '' and
-                      !Exists('%(_NetCoreAppRefPackGeneratorOutput.Identity)')"
-           Text="The shared framework generator output '%(_NetCoreAppRefPackGeneratorOutput.Identity)' does not exist." />
-
-    <ItemGroup Condition="'$(BuildProjectReferences)' != 'true' or '$(BuildingInsideVisualStudio)' == 'true'">
-      <_NetCoreAppRefPackGeneratorRelatedFile Include="@(_NetCoreAppRefPackGeneratorOutput)" />
-      <_NetCoreAppRefPackGeneratorRelatedFile Include="@(_NetCoreAppRefPackGeneratorOutput->'%(RootDir)%(Directory)%(Filename).pdb')" />
-      <_NetCoreAppRefPackGeneratorRelatedFile Include="%(_NetCoreAppRefPackGeneratorOutput.RootDir)%(_NetCoreAppRefPackGeneratorOutput.Directory)*\%(_NetCoreAppRefPackGeneratorOutput.Filename).resources.dll" />
+    <ItemGroup>
+      <_NetCoreAppRefPackGeneratorRelatedFile Include="@(_NetCoreAppRefPackGeneratorFile)" />
+      <_NetCoreAppRefPackGeneratorRelatedFile Include="@(_NetCoreAppRefPackGeneratorFile->'%(RootDir)%(Directory)%(Filename).pdb')" />
+      <_NetCoreAppRefPackGeneratorRelatedFile Include="%(_NetCoreAppRefPackGeneratorFile.RootDir)%(_NetCoreAppRefPackGeneratorFile.Directory)*\%(_NetCoreAppRefPackGeneratorFile.Filename).resources.dll" />
       <_NetCoreAppRefPackGeneratorRelatedFile Remove="@(_NetCoreAppRefPackGeneratorRelatedFile)"
                                               Condition="!Exists('%(_NetCoreAppRefPackGeneratorRelatedFile.Identity)')" />
-    </ItemGroup>
-
-    <ItemGroup>
       <_NetCoreAppLibraryPublicSourceAssembly Include="@(_NetCoreAppLibrarySourceAssembly)"
                                               Condition="'%(_NetCoreAppLibrarySourceAssembly.Extension)' == '.dll' and '%(_NetCoreAppLibrarySourceAssembly.IsPrivateAssembly)' != 'true'" />
       <_NetCoreAppLibrarySourceAssemblyWithReferenceAssembly Include="@(_NetCoreAppLibraryPublicSourceAssembly)"
@@ -69,10 +52,6 @@
       <_NetCoreAppLibrarySourceAssemblyWithDocumentation Include="@(_NetCoreAppLibraryPublicSourceAssembly)"
                                                          Condition="'%(_NetCoreAppLibraryPublicSourceAssembly.DocFileItem)' != '' and Exists('%(_NetCoreAppLibraryPublicSourceAssembly.DocFileItem)')" />
       <DocFilesToPackage Include="@(_NetCoreAppLibrarySourceAssemblyWithDocumentation->Metadata('DocFileItem'))" />
-      <FilesToPackage Include="@(_NetCoreAppRefPackGeneratorFile)"
-                      Condition="'%(_NetCoreAppRefPackGeneratorFile.PackagePath)' != ''"
-                      ExcludeFromValidation="true"
-                      TargetPath="analyzers/dotnet/cs/%(_NetCoreAppRefPackGeneratorFile.Culture)" />
       <FilesToPackage Include="@(_NetCoreAppRefPackGeneratorRelatedFile)"
                       ExcludeFromValidation="true"
                       TargetPath="analyzers/dotnet/cs/%(_NetCoreAppRefPackGeneratorRelatedFile.RecursiveDir)" />

From 328e370e920bc2b2401995ef71e4f007e2bd20b7 Mon Sep 17 00:00:00 2001
From: Jeremy Koritzinsky <jekoritz@microsoft.com>
Date: Thu, 3 Sep 2026 12:03:49 -0700
Subject: [PATCH 5/9] Use managed library resolution for managed consumers

Avoid requiring libs.native artifacts for NativeAOT tracing references and WebAssembly P/Invoke table generation.

Co-authored-by: Copilot App <223556219+Copilot@users.noreply.github.com>

Copilot-Session: a02d8ce4-72ef-40df-b3d2-8bea5d31d7a4
---
 src/mono/browser/browser.proj                         | 2 +-
 src/mono/wasi/wasi.proj                               | 2 +-
 src/tests/tracing/eventcounter/runtimecounters.csproj | 2 +-
 src/tests/tracing/eventpipe/Directory.Build.targets   | 2 +-
 4 files changed, 4 insertions(+), 4 deletions(-)

diff --git a/src/mono/browser/browser.proj b/src/mono/browser/browser.proj
index 710a36801a553b..b98e470596a40e 100644
--- a/src/mono/browser/browser.proj
+++ b/src/mono/browser/browser.proj
@@ -39,7 +39,7 @@
   </Target>
 
   <UsingTask TaskName="Microsoft.WebAssembly.Build.Tasks.Mono.ManagedToNativeGenerator" AssemblyFile="$(WasmAppBuilderTasksAssemblyPath)" TaskFactory="TaskHostFactory" />
-  <Target Name="GenerateManagedToNative" DependsOnTargets="CheckEnv;ResolveLibrariesFromLocalBuild">
+  <Target Name="GenerateManagedToNative" DependsOnTargets="CheckEnv;ResolveLibrariesManagedRuntimeFilesFromLocalBuild">
     <PropertyGroup>
       <WasmPInvokeTablePath>$(WasmObjDir)\pinvoke-table.h</WasmPInvokeTablePath>
       <WasmInterpToNativeTablePath>$(WasmObjDir)\wasm_m2n_invoke.g.h</WasmInterpToNativeTablePath>
diff --git a/src/mono/wasi/wasi.proj b/src/mono/wasi/wasi.proj
index 66fcd6e7fe4b71..c8408670ee032b 100644
--- a/src/mono/wasi/wasi.proj
+++ b/src/mono/wasi/wasi.proj
@@ -17,7 +17,7 @@
   </Target>
 
   <UsingTask TaskName="Microsoft.WebAssembly.Build.Tasks.Mono.ManagedToNativeGenerator" AssemblyFile="$(WasmAppBuilderTasksAssemblyPath)" />
-  <Target Name="GenerateManagedToNative" DependsOnTargets="CheckEnv;ResolveLibrariesFromLocalBuild">
+  <Target Name="GenerateManagedToNative" DependsOnTargets="CheckEnv;ResolveLibrariesManagedRuntimeFilesFromLocalBuild">
     <PropertyGroup>
       <WasmPInvokeTablePath>$(WasiObjDir)\pinvoke-table.h</WasmPInvokeTablePath>
       <WasmInterpToNativeTablePath>$(WasiObjDir)\wasm_m2n_invoke.g.h</WasmInterpToNativeTablePath>
diff --git a/src/tests/tracing/eventcounter/runtimecounters.csproj b/src/tests/tracing/eventcounter/runtimecounters.csproj
index 65765cf833dc31..11514bf23b6325 100644
--- a/src/tests/tracing/eventcounter/runtimecounters.csproj
+++ b/src/tests/tracing/eventcounter/runtimecounters.csproj
@@ -19,7 +19,7 @@
   -->
   <!-- Get all the *.dll files that has IsNative != "true"-->
   <Target Name="GetRequiredNativeAOTAssemblies"
-      DependsOnTargets="ResolveLibrariesRuntimeFilesFromLocalBuild"
+      DependsOnTargets="ResolveLibrariesManagedRuntimeFilesFromLocalBuild"
       BeforeTargets="ComputeIlcCompileInputs"
       Condition="'$(TestBuildMode)' == 'nativeaot'">
     <ItemGroup>
diff --git a/src/tests/tracing/eventpipe/Directory.Build.targets b/src/tests/tracing/eventpipe/Directory.Build.targets
index fd50f939a9c55e..6f9eb6518aeba0 100644
--- a/src/tests/tracing/eventpipe/Directory.Build.targets
+++ b/src/tests/tracing/eventpipe/Directory.Build.targets
@@ -7,7 +7,7 @@
   -->
   <!-- Get all the *.dll files that has IsNative != "true"-->
   <Target Name="GetRequiredNativeAOTAssemblies" 
-      DependsOnTargets="ResolveLibrariesRuntimeFilesFromLocalBuild"
+      DependsOnTargets="ResolveLibrariesManagedRuntimeFilesFromLocalBuild"
       BeforeTargets="ComputeIlcCompileInputs"
       Condition="'$(TestBuildMode)' == 'nativeaot'">
     <ItemGroup>

From 74406f120866d9e2c751129d51aed39eded1b63b Mon Sep 17 00:00:00 2001
From: Jeremy Koritzinsky <jekoritz@microsoft.com>
Date: Tue, 8 Sep 2026 18:18:37 -0700
Subject: [PATCH 6/9] Reference runtime managed pack inputs by project

Build CoreLib and NativeAOT managed assemblies through project references, extract MIBc merging into a dedicated producer, and let shared framework R2R process CoreLib consistently.

Co-authored-by: Copilot App <223556219+Copilot@users.noreply.github.com>

Copilot-Session: a02d8ce4-72ef-40df-b3d2-8bea5d31d7a4
---
 eng/codeOptimization.targets                  | 22 +++++-
 eng/liveBuilds.targets                        | 51 ++++++------
 src/coreclr/crossgen-corelib.proj             | 70 +++-------------
 src/coreclr/merge-mibc.proj                   | 79 +++++++++++++++++++
 src/coreclr/merge-mibc.targets                |  6 ++
 ...rosoft.NETCore.App.Runtime.CoreCLR.sfxproj | 46 ++++++++---
 ...Microsoft.NETCore.App.Runtime.Mono.sfxproj | 21 +++++
 ...soft.NETCore.App.Runtime.NativeAOT.sfxproj | 48 ++++++++++-
 .../Microsoft.NETCore.App.Runtime.props       | 22 ++++--
 src/libraries/Directory.Build.targets         |  5 ++
 src/libraries/sfx-src.proj                    |  2 +
 11 files changed, 264 insertions(+), 108 deletions(-)
 create mode 100644 src/coreclr/merge-mibc.proj
 create mode 100644 src/coreclr/merge-mibc.targets

diff --git a/eng/codeOptimization.targets b/eng/codeOptimization.targets
index 5f990a983476d7..f642bb21ceba0e 100644
--- a/eng/codeOptimization.targets
+++ b/eng/codeOptimization.targets
@@ -12,6 +12,24 @@
       <IsEligibleForNgenOptimization Condition="'$(TargetOS)' == 'osx' or '$(TargetsMobile)' == 'true'">false</IsEligibleForNgenOptimization>
   </PropertyGroup>
 
+  <PropertyGroup>
+    <_MibcConfiguration Condition="'$(CoreCLRConfiguration)' == ''">$(Configuration)</_MibcConfiguration>
+    <_MibcConfiguration Condition="'$(CoreCLRConfiguration)' != ''">$(CoreCLRConfiguration)</_MibcConfiguration>
+    <UseMibcProjectReference Condition="'$(UseMibcProjectReference)' == '' and
+                                        '$(PublishReadyToRun)' == 'true' and
+                                        '$(DotNetBuildSourceOnly)' != 'true'">true</UseMibcProjectReference>
+  </PropertyGroup>
+
+  <ItemGroup Condition="'$(UseMibcProjectReference)' == 'true'">
+    <ProjectReference Include="$(CoreClrProjectRoot)merge-mibc.proj"
+                      GlobalPropertiesToRemove="LibrariesRuntimeFlavor;RuntimeFlavor;RuntimeIdentifier;TargetFramework"
+                      OutputItemType="MergedMibcFile"
+                      ReferenceOutputAssembly="false"
+                      SetConfiguration="Configuration=$(_MibcConfiguration)"
+                      SkipGetTargetFrameworkProperties="true"
+                      Targets="Build;GetMibcFile" />
+  </ItemGroup>
+
   <Target Name="SetApplyNgenOptimization"
           Condition="'$(IsEligibleForNgenOptimization)' == 'true'"
           BeforeTargets="CoreCompile">
@@ -27,13 +45,13 @@
     </PropertyGroup>
   </Target>
 
-  <Target Name="AddReadyToRunPgoOptions" DependsOnTargets="ResolveRuntimeFilesFromLocalBuild" BeforeTargets="ResolveReadyToRunCompilers" Condition="'$(PublishReadyToRun)' == 'true'">
+  <Target Name="AddReadyToRunPgoOptions" DependsOnTargets="ResolveProjectReferences;ResolveRuntimeFilesFromLocalBuild" BeforeTargets="ResolveReadyToRunCompilers" Condition="'$(PublishReadyToRun)' == 'true'">
     <PropertyGroup>
       <!-- Only use mibc files if UsingToolIbcOptimization is false. Allows enabling/disabling using ibc instead of mibc data -->
       <IncludeMibcFilesInReadyToRun Condition="'$(UsingToolIbcOptimization)' != 'true' and '$(EnableNgenOptimization)' == 'true' and '$(DotNetBuildSourceOnly)' != 'true'">true</IncludeMibcFilesInReadyToRun>
     </PropertyGroup>
     <ItemGroup>
-      <PublishReadyToRunPgoFiles Condition="'$(IncludeMibcFilesInReadyToRun)' == 'true'" Include="$(CoreCLRArtifactsPath)StandardOptimizationData.mibc"/>
+      <PublishReadyToRunPgoFiles Condition="'$(IncludeMibcFilesInReadyToRun)' == 'true'" Include="@(MergedMibcFile)"/>
     </ItemGroup>
 
     <PropertyGroup Condition="'$(IncludeMibcFilesInReadyToRun)' == 'true'">
diff --git a/eng/liveBuilds.targets b/eng/liveBuilds.targets
index 0e650e92fffe8e..e1b4bef9511ade 100644
--- a/eng/liveBuilds.targets
+++ b/eng/liveBuilds.targets
@@ -1,19 +1,7 @@
 <Project>
-  <!-- Accept override paths for live artifacts. -->
+  <!-- Set up live asset paths. -->
   <PropertyGroup>
-    <CoreCLRArtifactsPath Condition="'$(CoreCLROverridePath)' != ''">$([MSBuild]::NormalizeDirectory('$(CoreCLROverridePath)'))</CoreCLRArtifactsPath>
-    <MonoArtifactsPath Condition="'$(MonoOverridePath)' != ''">$([MSBuild]::NormalizeDirectory('$(MonoOverridePath)'))</MonoArtifactsPath>
-    <LibrariesArtifactsPath Condition="'$(LibrariesOverridePath)' != ''">$([MSBuild]::NormalizeDirectory('$(LibrariesOverridePath)'))</LibrariesArtifactsPath>
-    <LibrariesAllConfigurationsArtifactsPath Condition="'$(LibrariesAllConfigurationsOverridePath)' != ''">$([MSBuild]::NormalizeDirectory('$(LibrariesAllConfigurationsOverridePath)'))</LibrariesAllConfigurationsArtifactsPath>
-
-    <!-- Honor the RuntimeArtifactsPath property. -->
-    <CoreCLRArtifactsPath Condition="'$(CoreCLRArtifactsPath)' == '' and '$(RuntimeArtifactsPath)' != ''">$([MSBuild]::NormalizeDirectory('$(RuntimeArtifactsPath)'))</CoreCLRArtifactsPath>
-    <MonoArtifactsPath Condition="'$(MonoArtifactsPath)' == '' and '$(RuntimeArtifactsPath)' != ''">$([MSBuild]::NormalizeDirectory('$(RuntimeArtifactsPath)'))</MonoArtifactsPath>
     <LibrariesTargetOSConfigurationArchitecture Condition="'$(LibrariesTargetOSConfigurationArchitecture)' == ''">$(TargetOS)-$(LibrariesConfiguration)-$(TargetArchitecture)</LibrariesTargetOSConfigurationArchitecture>
-  </PropertyGroup>
-
-  <!-- Set up default live asset paths if no overrides provided. -->
-  <PropertyGroup>
     <CoreCLRArtifactsPath Condition="'$(CoreCLRArtifactsPath)' == ''">$([MSBuild]::NormalizeDirectory('$(RepoRoot)', 'artifacts', 'bin', 'coreclr', '$(TargetOS).$(TargetArchitecture).$(CoreCLRConfiguration)'))</CoreCLRArtifactsPath>
     <MonoArtifactsPath Condition="'$(MonoArtifactsPath)' == ''">$([MSBuild]::NormalizeDirectory('$(RepoRoot)', 'artifacts', 'bin', 'mono', '$(TargetOS).$(TargetArchitecture).$(MonoConfiguration)'))</MonoArtifactsPath>
     <LibrariesArtifactsPath Condition="'$(LibrariesArtifactsPath)' == ''">$([MSBuild]::NormalizeDirectory('$(RepoRoot)', 'artifacts'))</LibrariesArtifactsPath>
@@ -101,7 +89,12 @@
     </PropertyGroup>
 
     <ItemGroup Condition="'$(BuildNativeAOTRuntimePack)' == 'true'">
-      <_nativeAotRuntimeFiles Include="$(CoreCLRAotSdkDir)*" />
+      <_nativeAotProjectOutputFile Include="@(_RuntimeCoreLibFile);@(_NativeAotRuntimeAssembly)" />
+      <_nativeAotRuntimeAssemblyFiles Include="@(_nativeAotProjectOutputFile->'$(CoreCLRAotSdkDir)%(Filename)%(Extension)');
+                                               @(_nativeAotProjectOutputFile->'$(CoreCLRAotSdkDir)%(Filename).pdb')"
+                                      Condition="'$(UseRuntimeManagedProjectReferences)' == 'true'" />
+      <_nativeAotRuntimeFiles Include="$(CoreCLRAotSdkDir)*"
+                              Exclude="@(_nativeAotRuntimeAssemblyFiles)" />
       <RuntimeFiles Include="@(_nativeAotRuntimeFiles)" Condition="'%(Extension)' != '.xml'">
         <IsNative>true</IsNative>
       </RuntimeFiles>
@@ -114,20 +107,25 @@
       <RuntimeFiles>
         <IsNative>true</IsNative>
       </RuntimeFiles>
-      <_systemPrivateCoreLib Include="$(CoreCLRArtifactsPath)System.Private.CoreLib.dll"
-                             Condition="Exists('$(CoreCLRArtifactsPath)System.Private.CoreLib.dll')" />
-      <_systemPrivateCoreLib Include="$(CoreCLRArtifactsPath)IL/System.Private.CoreLib.dll"
-                             Condition="Exists('$(CoreCLRArtifactsPath)IL/System.Private.CoreLib.dll') and '@(_systemPrivateCoreLib)' == ''" />
-      <RuntimeFiles Include="@(_systemPrivateCoreLib)" />
       <RuntimeFiles
         Include="
           $(CoreCLRSharedFrameworkPdbDir)*.pdb;
           $(CoreCLRSharedFrameworkPdbDir)*.dbg;
           $(CoreCLRSharedFrameworkPdbDir)*.dwarf" IsNative="true" />
-      <RuntimeFiles Condition="Exists('$(CoreCLRArtifactsPdbDir)System.Private.CoreLib.pdb')"
-        Include="$(CoreCLRArtifactsPdbDir)System.Private.CoreLib.pdb" />
-      <RuntimeFiles Condition="Exists('$(CoreCLRArtifactsPdbDir)System.Private.CoreLib.ni.pdb')"
-        Include="$(CoreCLRArtifactsPdbDir)System.Private.CoreLib.ni.pdb" />
+      <_systemPrivateCoreLib Include="$(CoreCLRArtifactsPath)System.Private.CoreLib.dll"
+                             Condition="'$(UseRuntimeManagedProjectReferences)' != 'true' and
+                                        Exists('$(CoreCLRArtifactsPath)System.Private.CoreLib.dll')" />
+      <_systemPrivateCoreLib Include="$(CoreCLRArtifactsPath)IL/System.Private.CoreLib.dll"
+                             Condition="'$(UseRuntimeManagedProjectReferences)' != 'true' and
+                                        Exists('$(CoreCLRArtifactsPath)IL/System.Private.CoreLib.dll') and
+                                        '@(_systemPrivateCoreLib)' == ''" />
+      <RuntimeFiles Include="@(_systemPrivateCoreLib)" />
+      <RuntimeFiles Condition="'$(UseRuntimeManagedProjectReferences)' != 'true' and
+                               Exists('$(CoreCLRArtifactsPdbDir)System.Private.CoreLib.pdb')"
+                    Include="$(CoreCLRArtifactsPdbDir)System.Private.CoreLib.pdb" />
+      <RuntimeFiles Condition="'$(UseRuntimeManagedProjectReferences)' != 'true' and
+                               Exists('$(CoreCLRArtifactsPdbDir)System.Private.CoreLib.ni.pdb')"
+                    Include="$(CoreCLRArtifactsPdbDir)System.Private.CoreLib.ni.pdb" />
 
       <CoreCLRCrossTargetFiles Condition="'$(CoreCLRCrossTargetComponentDir)' != ''"
         Include="
@@ -141,7 +139,12 @@
       </CoreCLRCrossTargetFiles>
     </ItemGroup>
     <ItemGroup Condition="'$(RuntimeFlavor)' == 'Mono'">
-      <RuntimeFiles Include="$(MonoArtifactsPath)\*.*" Exclude="$(MonoArtifactsPath)\*cdac*" />
+      <_monoRuntimeManagedProjectFiles Include="$(MonoArtifactsPath)\System.Private.CoreLib.dll;
+                                                $(MonoArtifactsPath)\System.Private.CoreLib.pdb"
+                                       Condition="'$(UseRuntimeManagedProjectReferences)' == 'true'" />
+      <RuntimeFiles Include="$(MonoArtifactsPath)\*.*"
+                    Exclude="$(MonoArtifactsPath)\*cdac*;
+                             @(_monoRuntimeManagedProjectFiles)" />
       <RuntimeFiles>
         <IsNative>true</IsNative>
       </RuntimeFiles>
diff --git a/src/coreclr/crossgen-corelib.proj b/src/coreclr/crossgen-corelib.proj
index ebe09a78aa9dad..384a5cfe7a15f0 100644
--- a/src/coreclr/crossgen-corelib.proj
+++ b/src/coreclr/crossgen-corelib.proj
@@ -2,7 +2,13 @@
 
   <ItemGroup>
     <ProjectReference Include="$(CoreClrProjectRoot)/tools/aot/crossgen2/crossgen2_inbuild.csproj" OutputItemType="Crossgen2Files" />
-    <ProjectReference Include="$(CoreClrProjectRoot)/tools/dotnet-pgo/dotnet-pgo.csproj" OutputItemType="DotNetPgo" Condition="'$(DotNetBuildSourceOnly)' != 'true'" />
+    <ProjectReference Include="$(CoreClrProjectRoot)merge-mibc.proj"
+                      GlobalPropertiesToRemove="LibrariesRuntimeFlavor;RuntimeFlavor;RuntimeIdentifier;TargetFramework"
+                      OutputItemType="MergedMibcFile"
+                      ReferenceOutputAssembly="false"
+                      SetConfiguration="Configuration=$(CoreCLRConfiguration)"
+                      SkipGetTargetFrameworkProperties="true"
+                      Targets="Build;GetMibcFile" />
     <ProjectReference Include="$([MSBuild]::NormalizePath('$(CoreClrProjectRoot)', 'System.Private.CoreLib', 'System.Private.CoreLib.csproj'))" OutputItemType="CoreLib" />
   </ItemGroup>
 
@@ -12,8 +18,6 @@
     <LogsDir>$([MSBuild]::NormalizeDirectory('$(RootBinDir)', 'log'))</LogsDir>
     <BinDir>$([MSBuild]::NormalizeDirectory('$(RootBinDir)', 'bin', 'coreclr', $(OSPlatformConfig)))</BinDir>
     <IntermediatesDir>$([MSBuild]::NormalizeDirectory('$(RootBinDir)', 'obj', 'coreclr', $(OSPlatformConfig)))</IntermediatesDir>
-    <DotNetCli>$([MSBuild]::NormalizePath('$(RepoRoot)', 'dotnet.sh'))</DotNetCli>
-    <DotNetCli Condition="'$(OS)' == 'Windows_NT'">$([MSBuild]::NormalizePath('$(RepoRoot)', 'dotnet.cmd'))</DotNetCli>
   </PropertyGroup>
 
   <PropertyGroup>
@@ -30,8 +34,6 @@
 
     <BuildPerfMap>false</BuildPerfMap>
     <BuildPerfMap Condition="'$(TargetOS)' == 'linux'">true</BuildPerfMap>
-
-    <_MergeMibcFilesCacheFile>$(MibcOptimizationDataDir)/$(TargetOS)/$(TargetArchitecture)/merge_mibc_files.cache</_MergeMibcFilesCacheFile>
   </PropertyGroup>
 
   <PropertyGroup Condition="'$(TargetsAppleMobile)' == 'true' and $(PublishReadyToRun)">
@@ -49,10 +51,6 @@
     <CrossgenTargetName>$(CrossgenTargetName);CopyR2RComponentCoreLib</CrossgenTargetName>
   </PropertyGroup>
 
-  <ItemGroup>
-    <OptimizationMibcFiles Include="$(MibcOptimizationDataDir)/$(TargetOS)/$(TargetArchitecture)/**/*.mibc" />
-  </ItemGroup>
-
   <PropertyGroup>
     <CoreLibAssemblyName>System.Private.CoreLib</CoreLibAssemblyName>
     <CoreLibOutputPath>$([MSBuild]::NormalizePath('$(BinDir)', '$(CoreLibAssemblyName).dll'))</CoreLibOutputPath>
@@ -62,7 +60,6 @@
     <CoreLibPerfMapPath></CoreLibPerfMapPath>
     <CoreLibNiPdbPath Condition="$(BuildPdb)">$([MSBuild]::NormalizePath('$(BinDir)', 'PDB', '$(CoreLibAssemblyName).ni.pdb'))</CoreLibNiPdbPath>
     <CoreLibPerfMapPath Condition="$(BuildPerfMap)">$([MSBuild]::NormalizePath('$(BinDir)', '$(CoreLibAssemblyName).ni.r2rmap'))</CoreLibPerfMapPath>
-    <MergedMibcPath>$([MSBuild]::NormalizePath('$(BinDir)', 'StandardOptimizationData.mibc'))</MergedMibcPath>
   </PropertyGroup>
 
   <PropertyGroup Condition="'$(PublishReadyToRunContainerFormat)' == 'macho'">
@@ -79,55 +76,10 @@
     <CrossgenCoreLibComponentOutputPath>$([MSBuild]::NormalizePath('$(IntermediateOutputPath)', '$(CoreLibAssemblyName).dll'))</CrossgenCoreLibComponentOutputPath>
   </PropertyGroup>
 
-  <!-- Creates a hash file that changes whenever the input mibc file modification times change.
-       This will trigger a re-merge when updating to a new version of the optimization data,
-       even if the new timestamps are still days in the past. -->
-  <Target Name="GenerateMergeMibcFilesInputCache">
-    <ItemGroup>
-      <_MergeMibcFilesInputCache Include="@(OptimizationMibcFiles)" />
-      <_MergeMibcFilesInputCache Include="@(DotNetPgo)" />
-      <_MergeMibcFilesInputCache Include="@(OptimizationMibcFiles->'%(ModifiedTime)')" />
-    </ItemGroup>
-
-    <Hash ItemsToHash="@(_MergeMibcFilesInputCache)">
-      <Output TaskParameter="HashResult" PropertyName="_MergeMibcFilesInputCacheHash" />
-    </Hash>
-
-    <WriteLinesToFile
-      Lines="$(_MergeMibcFilesInputCacheHash)"
-      File="$(_MergeMibcFilesCacheFile)"
-      Overwrite="true"
-      WriteOnlyWhenDifferent="true" />
-
-    <ItemGroup>
-      <FileWrites Include="$(_MergeMibcFilesCacheFile)" />
-    </ItemGroup>
-  </Target>
-
-  <Target Name="MergeMibcFiles"
-          DependsOnTargets="GenerateMergeMibcFilesInputCache"
-          Inputs="$(_MergeMibcFilesCacheFile);@(OptimizationMibcFiles);@(DotNetPgo)"
-          Condition="'@(DotNetPgo)' != ''"
-          Outputs="$(MergedMibcPath)">
-
-    <PropertyGroup>
-      <DotNetPgoCmd>$(DotNetCli) @(DotNetPgo) merge</DotNetPgoCmd>
-      <DotNetPgoCmd>$(DotNetPgoCmd) -o:$(MergedMibcPath)</DotNetPgoCmd>
-      <DotNetPgoCmd>$(DotNetPgoCmd) @(OptimizationMibcFiles->'-i:%(Identity)', ' ')</DotNetPgoCmd>
-      <DotNetPgoCmd>$(DotNetPgoCmd) --compressed false</DotNetPgoCmd> <!-- Signing service doesn't handle compressed mibc signing correctly. -->
-    </PropertyGroup>
-
-    <Message Importance="High" Text="$(DotNetPgoCmd)"/>
-    <Exec Command="$(DotNetPgoCmd)" />
-  </Target>
-
-  <Target Name="CreateMergedMibcFile"
-          DependsOnTargets="ResolveProjectReferences;MergeMibcFiles" />
-
-  <Target Name="PrepareInvokeCrossgen2" DependsOnTargets="ResolveProjectReferences;CreateMergedMibcFile">
+  <Target Name="PrepareInvokeCrossgen2" DependsOnTargets="ResolveProjectReferences">
     <ItemGroup>
       <Crossgen2Inputs Include="@(CoreLib)" />
-      <Crossgen2Inputs Include="$(MergedMibcPath)" />
+      <Crossgen2Inputs Include="@(MergedMibcFile)" />
       <Crossgen2Inputs Include="@(Crossgen2Files->Metadata('OutputPath'))" />
     </ItemGroup>
   </Target>
@@ -140,7 +92,7 @@
   </Target>
 
   <Target Name="InvokeCrossgen2"
-          DependsOnTargets="PrepareInvokeCrossgen2;CreateMergedMibcFile"
+          DependsOnTargets="PrepareInvokeCrossgen2"
           Inputs="@(Crossgen2Inputs)"
           Outputs="$(CoreLibOutputPath);$(CoreLibNiPdbPath);$(CoreLibPerfMapPath);$(CrossgenCoreLibOutputPath);$(CrossgenCoreLibComponentOutputPath)">
 
@@ -162,7 +114,7 @@
       <CrossGenDllCmd Condition="'$(UseComposite)' == 'true'">$(CrossGenDllCmd) --composite</CrossGenDllCmd>
       <CrossGenDllCmd>$(CrossGenDllCmd) --targetos:$(TargetOS)</CrossGenDllCmd>
       <CrossGenDllCmd Condition="'$(FeatureDynamicCodeCompiled)' != ''">$(CrossGenDllCmd) --target-allows-runtime-code-generation:$(FeatureDynamicCodeCompiled)</CrossGenDllCmd>
-      <CrossGenDllCmd Condition="'$(UsingToolIbcOptimization)' != 'true' and '$(EnableNgenOptimization)' == 'true'">$(CrossGenDllCmd) -m:$(MergedMibcPath) --embed-pgo-data</CrossGenDllCmd>
+      <CrossGenDllCmd Condition="'$(UsingToolIbcOptimization)' != 'true' and '$(EnableNgenOptimization)' == 'true'">$(CrossGenDllCmd) -m:@(MergedMibcFile) --embed-pgo-data</CrossGenDllCmd>
       <CrossGenDllCmd>$(CrossGenDllCmd) -O</CrossGenDllCmd>
       <!-- Enable type and field layout verification to make it easier to catch when the crossgen2 type layout engine and the runtime disagree on layout conventions -->
       <CrossGenDllCmd  Condition="'$(Configuration)' == 'Debug' or '$(Configuration)' == 'Checked'">$(CrossGenDllCmd) --verify-type-and-field-layout</CrossGenDllCmd>
diff --git a/src/coreclr/merge-mibc.proj b/src/coreclr/merge-mibc.proj
new file mode 100644
index 00000000000000..0ccd19135294e1
--- /dev/null
+++ b/src/coreclr/merge-mibc.proj
@@ -0,0 +1,79 @@
+<Project Sdk="Microsoft.Build.NoTargets">
+
+  <ItemGroup>
+    <ProjectReference Include="$(CoreClrProjectRoot)tools\dotnet-pgo\dotnet-pgo.csproj"
+                      Condition="'$(DotNetBuildSourceOnly)' != 'true'"
+                      OutputItemType="DotNetPgo" />
+  </ItemGroup>
+
+  <PropertyGroup>
+    <CustomAfterNoTargets>$(MSBuildThisFileDirectory)merge-mibc.targets</CustomAfterNoTargets>
+    <OSPlatformConfig>$(TargetOS).$(TargetArchitecture).$(Configuration)</OSPlatformConfig>
+    <BinDir>$([MSBuild]::NormalizeDirectory('$(ArtifactsBinDir)', 'coreclr', '$(OSPlatformConfig)'))</BinDir>
+    <DotNetCli>$([MSBuild]::NormalizePath('$(RepoRoot)', 'dotnet.sh'))</DotNetCli>
+    <DotNetCli Condition="'$(OS)' == 'Windows_NT'">$([MSBuild]::NormalizePath('$(RepoRoot)', 'dotnet.cmd'))</DotNetCli>
+    <MergedMibcPath>$([MSBuild]::NormalizePath('$(BinDir)', 'StandardOptimizationData.mibc'))</MergedMibcPath>
+    <_MergeMibcFilesCacheFile>$(MibcOptimizationDataDir)/$(TargetOS)/$(TargetArchitecture)/merge_mibc_files.cache</_MergeMibcFilesCacheFile>
+  </PropertyGroup>
+
+  <ItemGroup>
+    <MergedMibcFile Include="$(MergedMibcPath)" />
+    <OptimizationMibcFile Include="$(MibcOptimizationDataDir)/$(TargetOS)/$(TargetArchitecture)/**/*.mibc" />
+  </ItemGroup>
+
+  <!-- Creates a hash file that changes whenever the input mibc file modification times change.
+       This will trigger a re-merge when updating to a new version of the optimization data,
+       even if the new timestamps are still days in the past. -->
+  <Target Name="GenerateMergeMibcFilesInputCache">
+    <ItemGroup>
+      <_MergeMibcFilesInputCache Include="@(OptimizationMibcFile)" />
+      <_MergeMibcFilesInputCache Include="@(DotNetPgo)" />
+      <_MergeMibcFilesInputCache Include="@(OptimizationMibcFile->'%(ModifiedTime)')" />
+    </ItemGroup>
+
+    <Hash ItemsToHash="@(_MergeMibcFilesInputCache)">
+      <Output TaskParameter="HashResult" PropertyName="_MergeMibcFilesInputCacheHash" />
+    </Hash>
+
+    <WriteLinesToFile
+      Lines="$(_MergeMibcFilesInputCacheHash)"
+      File="$(_MergeMibcFilesCacheFile)"
+      Overwrite="true"
+      WriteOnlyWhenDifferent="true" />
+
+    <ItemGroup>
+      <FileWrites Include="$(_MergeMibcFilesCacheFile)" />
+    </ItemGroup>
+  </Target>
+
+  <Target Name="MergeMibcFiles"
+          DependsOnTargets="GenerateMergeMibcFilesInputCache"
+          Inputs="$(_MergeMibcFilesCacheFile);@(OptimizationMibcFile);@(DotNetPgo)"
+          Condition="'@(DotNetPgo)' != ''"
+          Outputs="@(MergedMibcFile)">
+    <PropertyGroup>
+      <DotNetPgoCmd>$(DotNetCli) @(DotNetPgo) merge</DotNetPgoCmd>
+      <DotNetPgoCmd>$(DotNetPgoCmd) -o:@(MergedMibcFile)</DotNetPgoCmd>
+      <DotNetPgoCmd>$(DotNetPgoCmd) @(OptimizationMibcFile->'-i:%(Identity)', ' ')</DotNetPgoCmd>
+      <DotNetPgoCmd>$(DotNetPgoCmd) --compressed false</DotNetPgoCmd> <!-- Signing service doesn't handle compressed mibc signing correctly. -->
+    </PropertyGroup>
+
+    <MakeDir Directories="$(BinDir)" />
+    <Message Importance="High" Text="$(DotNetPgoCmd)"/>
+    <Exec Command="$(DotNetPgoCmd)" />
+  </Target>
+
+  <Target Name="BuildMibcFile"
+          AfterTargets="CoreBuild"
+          DependsOnTargets="ResolveProjectReferences;MergeMibcFiles" />
+
+  <Target Name="GetMibcFile"
+          DependsOnTargets="BuildMibcFile"
+          Returns="@(MergedMibcFile)" />
+
+  <Target Name="CleanMibcFile"
+          AfterTargets="Clean">
+    <Delete Files="@(MergedMibcFile);$(_MergeMibcFilesCacheFile)" />
+  </Target>
+
+</Project>
diff --git a/src/coreclr/merge-mibc.targets b/src/coreclr/merge-mibc.targets
new file mode 100644
index 00000000000000..dbfeb66422a4de
--- /dev/null
+++ b/src/coreclr/merge-mibc.targets
@@ -0,0 +1,6 @@
+<Project>
+
+  <Target Name="GetTargetPath"
+          Returns="@(MergedMibcFile)" />
+
+</Project>
diff --git a/src/installer/pkg/sfx/Microsoft.NETCore.App/Microsoft.NETCore.App.Runtime.CoreCLR.sfxproj b/src/installer/pkg/sfx/Microsoft.NETCore.App/Microsoft.NETCore.App.Runtime.CoreCLR.sfxproj
index 1cbc5c78a0649f..5a59bdc91218ae 100644
--- a/src/installer/pkg/sfx/Microsoft.NETCore.App/Microsoft.NETCore.App.Runtime.CoreCLR.sfxproj
+++ b/src/installer/pkg/sfx/Microsoft.NETCore.App/Microsoft.NETCore.App.Runtime.CoreCLR.sfxproj
@@ -31,6 +31,7 @@
     <UsesMuxerHostModel Condition="'$(TargetsMobile)' != 'true'">true</UsesMuxerHostModel>
     <IncludeDiaSymReaderNative Condition="'$(TargetOS)' == 'windows'">true</IncludeDiaSymReaderNative>
     <UseLocalCrossgen2Pack>$(PublishReadyToRun)</UseLocalCrossgen2Pack>
+    <_PublishReadyToRunCrossgen2ExtraArgs Condition="'$(FeatureDynamicCodeCompiled)' != ''">$(_PublishReadyToRunCrossgen2ExtraArgs);--target-allows-runtime-code-generation:$(FeatureDynamicCodeCompiled)</_PublishReadyToRunCrossgen2ExtraArgs>
   </PropertyGroup>
 
   <PropertyGroup Condition="'$(TargetOS)' == 'browser' and '$(PublishReadyToRun)' == 'true'">
@@ -38,7 +39,7 @@
     <PublishReadyToRunComposite>false</PublishReadyToRunComposite>
     <PublishReadyToRunContainerFormat>wasm</PublishReadyToRunContainerFormat>
     <PublishReadyToRunEmitSymbols>false</PublishReadyToRunEmitSymbols>
-    <_PublishReadyToRunCrossgen2ExtraArgs>--opt-cross-module:*;--codegenopt:JitWasmNyiToR2RUnsupported=1;--codegenopt:JitWasmSimdNyiToR2RUnsupported=1</_PublishReadyToRunCrossgen2ExtraArgs>
+    <_PublishReadyToRunCrossgen2ExtraArgs>$(_PublishReadyToRunCrossgen2ExtraArgs);--opt-cross-module:*;--codegenopt:JitWasmNyiToR2RUnsupported=1;--codegenopt:JitWasmSimdNyiToR2RUnsupported=1</_PublishReadyToRunCrossgen2ExtraArgs>
   </PropertyGroup>
 
   <!-- Use the Mach-O format for Apple mobile platforms as we can't load native code from PE files on these platforms -->
@@ -47,6 +48,31 @@
     <PublishReadyToRunContainerFormat>macho</PublishReadyToRunContainerFormat>
   </PropertyGroup>
 
+  <PropertyGroup>
+    <CoreLibConfiguration>$(CoreCLRConfiguration)</CoreLibConfiguration>
+    <LibrariesRuntimeFlavor Condition="'$(LibrariesRuntimeFlavor)' == ''">CoreCLR</LibrariesRuntimeFlavor>
+    <UseRuntimeManagedProjectReferences>true</UseRuntimeManagedProjectReferences>
+    <UseMibcProjectReference>true</UseMibcProjectReference>
+  </PropertyGroup>
+
+  <ItemGroup>
+  </ItemGroup>
+
+  <Target Name="AddCoreCLRRuntimeManagedFiles"
+          BeforeTargets="AddRuntimeFilesToPackage"
+          DependsOnTargets="ResolveProjectReferences">
+    <ItemGroup>
+      <RuntimeFiles Include="@(_RuntimeCoreLibFile)" />
+    </ItemGroup>
+  </Target>
+
+  <Target Name="ResolveRuntimeMibcFile"
+          DependsOnTargets="ResolveProjectReferences">
+    <ItemGroup>
+      <RuntimeMibcFile Include="@(MergedMibcFile)" />
+    </ItemGroup>
+  </Target>
+
   <Import Project="Microsoft.NETCore.App.Runtime.props" />
 
   <PropertyGroup>
@@ -87,19 +113,16 @@
       <_WasmFrameworkR2RExclude Include="@(_WasmFrameworkR2RReference)"
                                 Exclude="@(_WasmFrameworkR2RInput)" />
       <PublishReadyToRunExclude Include="@(_WasmFrameworkR2RExclude->'%(FileName)%(Extension)')" />
-      <PublishReadyToRunExclude Include="System.Private.CoreLib.dll" />
     </ItemGroup>
     <PropertyGroup>
-      <_WasmCoreLibIL Condition="Exists('$(CoreCLRArtifactsPath)System.Private.CoreLib.dll')">$(CoreCLRArtifactsPath)System.Private.CoreLib.dll</_WasmCoreLibIL>
-      <_WasmCoreLibIL Condition="'$(_WasmCoreLibIL)' == '' and Exists('$(CoreCLRArtifactsPath)IL\System.Private.CoreLib.dll')">$(CoreCLRArtifactsPath)IL\System.Private.CoreLib.dll</_WasmCoreLibIL>
       <_WasmCrossgen2Exe>$([MSBuild]::NormalizePath('$(Crossgen2InBuildDir)', 'crossgen2$(ExeSuffix)'))</_WasmCrossgen2Exe>
     </PropertyGroup>
-    <Error Condition="'$(_WasmCoreLibIL)' == ''"
-           Text="PublishReadyToRun is true but System.Private.CoreLib IL was not found under '$(CoreCLRArtifactsPath)'. Build CoreCLR first or set PublishReadyToRun=false." />
+    <Error Condition="'@(_RuntimeCoreLibFile)' == ''"
+           Text="PublishReadyToRun is true but the System.Private.CoreLib project did not produce its IL assembly. Build CoreCLR first or set PublishReadyToRun=false." />
     <Error Condition="!Exists('$(_WasmCrossgen2Exe)')"
            Text="PublishReadyToRun is true but crossgen2 was not found at '$(_WasmCrossgen2Exe)'. Build the crossgen2 pack or set PublishReadyToRun=false." />
     <ItemGroup>
-      <_ReadyToRunCompilerInputs Include="@(_WasmFrameworkR2RReference);$(_WasmCoreLibIL)" />
+      <_ReadyToRunCompilerInputs Include="@(_WasmFrameworkR2RReference);@(_RuntimeCoreLibFile)" />
       <_ReadyToRunCompilerInputs Include="$(Crossgen2InBuildDir)*jit*.dll;$(Crossgen2InBuildDir)*jit*.dylib;$(Crossgen2InBuildDir)*jit*.so" />
     </ItemGroup>
   </Target>
@@ -111,8 +134,6 @@
       <_WasmFrameworkR2RCompileInput Include="@(_ReadyToRunCompileList)"
                                      Condition="$([System.String]::Copy('%(OutputR2RImage)').EndsWith('.wasm'))" />
       <_WasmFrameworkR2ROutput Include="@(_WasmFrameworkR2RCompileInput->'%(OutputR2RImage)')" />
-      <_WasmFrameworkR2ROutput Include="$(CoreCLRArtifactsPath)System.Private.CoreLib.wasm"
-                               Condition="Exists('$(CoreCLRArtifactsPath)System.Private.CoreLib.wasm')" />
       <FilesToPackage Include="@(_WasmFrameworkR2RCompileInput)"
                       IsNative=""
                       DestinationSubDirectory=""
@@ -149,10 +170,11 @@
     Putting it in tools will also hide it from being part of the RuntimeList.xml.
   -->
   <Target Name="AddMibcFilesToPackage"
-          AfterTargets="GetFilesToPackage">
+          AfterTargets="GetFilesToPackage"
+          DependsOnTargets="ResolveRuntimeMibcFile">
     <ItemGroup>
-      <FilesToPackageMibcData Include="$(CoreCLRArtifactsPath)StandardOptimizationData.mibc"
-                              Condition="Exists('$(CoreCLRArtifactsPath)StandardOptimizationData.mibc')">
+      <FilesToPackageMibcData Include="@(RuntimeMibcFile)"
+                              Condition="Exists('%(RuntimeMibcFile.Identity)')">
         <TargetPath>tools</TargetPath>
       </FilesToPackageMibcData>
       <FilesToPackage Include="@(FilesToPackageMibcData)"/>
diff --git a/src/installer/pkg/sfx/Microsoft.NETCore.App/Microsoft.NETCore.App.Runtime.Mono.sfxproj b/src/installer/pkg/sfx/Microsoft.NETCore.App/Microsoft.NETCore.App.Runtime.Mono.sfxproj
index f074aa4c2e5e06..638a82e747177f 100644
--- a/src/installer/pkg/sfx/Microsoft.NETCore.App/Microsoft.NETCore.App.Runtime.Mono.sfxproj
+++ b/src/installer/pkg/sfx/Microsoft.NETCore.App/Microsoft.NETCore.App.Runtime.Mono.sfxproj
@@ -44,6 +44,27 @@
     <OverridePackageId>$(SharedFrameworkName).Runtime.$(RuntimeSpecificFrameworkSuffix).$(RuntimeIdentifier)</OverridePackageId>
   </PropertyGroup>
 
+  <PropertyGroup>
+    <CoreLibConfiguration>$(MonoConfiguration)</CoreLibConfiguration>
+    <LibrariesRuntimeFlavor Condition="'$(LibrariesRuntimeFlavor)' == ''">Mono</LibrariesRuntimeFlavor>
+    <UseRuntimeManagedProjectReferences>true</UseRuntimeManagedProjectReferences>
+  </PropertyGroup>
+
+  <ItemGroup>
+  </ItemGroup>
+
+  <Target Name="AddMonoCoreLibToRuntimeFiles"
+          BeforeTargets="AddRuntimeFilesToPackage"
+          DependsOnTargets="ResolveProjectReferences">
+    <ItemGroup>
+      <_RuntimeCoreLibSymbol Include="@(_RuntimeCoreLibFile->'%(RootDir)%(Directory)%(Filename).pdb')" />
+      <_RuntimeCoreLibSymbol Remove="@(_RuntimeCoreLibSymbol)"
+                             Condition="!Exists('%(_RuntimeCoreLibSymbol.Identity)')" />
+      <RuntimeFiles Include="@(_RuntimeCoreLibFile);@(_RuntimeCoreLibSymbol)"
+                    IsNative="true" />
+    </ItemGroup>
+  </Target>
+
   <Import Project="Microsoft.NETCore.App.Runtime.props" />
 
   <Target Name="AddMonoRuntimeFiles" AfterTargets="AddRuntimeFilesToPackage">
diff --git a/src/installer/pkg/sfx/Microsoft.NETCore.App/Microsoft.NETCore.App.Runtime.NativeAOT.sfxproj b/src/installer/pkg/sfx/Microsoft.NETCore.App/Microsoft.NETCore.App.Runtime.NativeAOT.sfxproj
index 34587e9fa80607..738c684a9169e3 100644
--- a/src/installer/pkg/sfx/Microsoft.NETCore.App/Microsoft.NETCore.App.Runtime.NativeAOT.sfxproj
+++ b/src/installer/pkg/sfx/Microsoft.NETCore.App/Microsoft.NETCore.App.Runtime.NativeAOT.sfxproj
@@ -1,4 +1,4 @@
-<Project TreatAsLocalProperty="RuntimeFlavor;BuildNativeAOTRuntimePack">
+<Project TreatAsLocalProperty="RuntimeFlavor;BuildNativeAOTRuntimePack;LibrariesRuntimeFlavor">
   <PropertyGroup>
     <RuntimeFlavor>CoreCLR</RuntimeFlavor>
     <BuildNativeAOTRuntimePack>true</BuildNativeAOTRuntimePack>
@@ -18,12 +18,54 @@
     <IncludeStaticLibrariesInPack>true</IncludeStaticLibrariesInPack>
   </PropertyGroup>
 
+  <PropertyGroup>
+    <CoreLibConfiguration>$(CoreCLRConfiguration)</CoreLibConfiguration>
+    <CoreLibProject>$([MSBuild]::NormalizePath('$(CoreClrProjectRoot)', 'nativeaot', 'System.Private.CoreLib', 'src', 'System.Private.CoreLib.csproj'))</CoreLibProject>
+    <LibrariesRuntimeFlavor>CoreCLR</LibrariesRuntimeFlavor>
+    <UseRuntimeManagedProjectReferences>true</UseRuntimeManagedProjectReferences>
+    <UseMibcProjectReference>true</UseMibcProjectReference>
+  </PropertyGroup>
+
   <ItemGroup>
     <IgnoredDuplicateType Include="Internal.Runtime.CompilerHelpers.LibraryInitializer" />
-    <FilesToPackage Include="$(CoreCLRArtifactsPath)StandardOptimizationData.mibc"
-                    Condition="Exists('$(CoreCLRArtifactsPath)StandardOptimizationData.mibc')" />
+    <ProjectReference Include="$(CoreClrProjectRoot)nativeaot\System.Private.*\src\*.csproj"
+                      AdditionalProperties="BuildAllProjects=true"
+                      Exclude="$(CoreLibProject)"
+                      GlobalPropertiesToRemove="LibrariesRuntimeFlavor;RuntimeFlavor;RuntimeIdentifier;TargetFramework"
+                      OutputItemType="_NativeAotRuntimeAssembly"
+                      ReferenceOutputAssembly="false"
+                      SetConfiguration="Configuration=$(CoreCLRConfiguration)"
+                      SkipGetTargetFrameworkProperties="true" />
   </ItemGroup>
 
+  <Target Name="AddNativeAOTManagedAssembliesToRuntimeFiles"
+          BeforeTargets="AddRuntimeFilesToPackage"
+          DependsOnTargets="ResolveProjectReferences">
+    <ItemGroup>
+      <_NativeAotRuntimeManagedAssembly Include="@(_RuntimeCoreLibFile);@(_NativeAotRuntimeAssembly)" />
+      <_NativeAotRuntimeAssemblySymbol Include="@(_NativeAotRuntimeManagedAssembly->'%(RootDir)%(Directory)%(Filename).pdb')" />
+      <_NativeAotRuntimeAssemblySymbol Remove="@(_NativeAotRuntimeAssemblySymbol)"
+                                       Condition="!Exists('%(_NativeAotRuntimeAssemblySymbol.Identity)')" />
+      <RuntimeFiles Include="@(_NativeAotRuntimeManagedAssembly);@(_NativeAotRuntimeAssemblySymbol)"
+                    IsNative="true" />
+    </ItemGroup>
+  </Target>
+
+  <Target Name="ResolveRuntimeMibcFile"
+          DependsOnTargets="ResolveProjectReferences">
+    <ItemGroup>
+      <RuntimeMibcFile Include="@(MergedMibcFile)" />
+    </ItemGroup>
+  </Target>
+
+  <Target Name="AddMibcFileToNativeAOTPackage"
+          BeforeTargets="GetFilesToPackage"
+          DependsOnTargets="ResolveRuntimeMibcFile">
+    <ItemGroup>
+      <FilesToPackage Include="@(RuntimeMibcFile)"
+                      Condition="Exists('%(RuntimeMibcFile.Identity)')" />
+    </ItemGroup>
+  </Target>
 
   <Import Project="Microsoft.NETCore.App.Runtime.props" />
 
diff --git a/src/installer/pkg/sfx/Microsoft.NETCore.App/Microsoft.NETCore.App.Runtime.props b/src/installer/pkg/sfx/Microsoft.NETCore.App/Microsoft.NETCore.App.Runtime.props
index 2449e70a676069..19d04378ad42fe 100644
--- a/src/installer/pkg/sfx/Microsoft.NETCore.App/Microsoft.NETCore.App.Runtime.props
+++ b/src/installer/pkg/sfx/Microsoft.NETCore.App/Microsoft.NETCore.App.Runtime.props
@@ -1,20 +1,25 @@
 <Project>
-  <Import Project="$(LibrariesProjectRoot)NetCoreAppLibraryProjectReferences.props" />
-
   <ItemGroup>
+    <ProjectReference Include="$(CoreLibProject)"
+                      AdditionalProperties="BuildAllProjects=true"
+                      GlobalPropertiesToRemove="LibrariesRuntimeFlavor;RuntimeFlavor;RuntimeIdentifier;TargetFramework"
+                      OutputItemType="_RuntimeCoreLibFile"
+                      ReferenceOutputAssembly="false"
+                      SetConfiguration="Configuration=$(CoreLibConfiguration)"
+                      SkipGetTargetFrameworkProperties="true" />
     <ProjectReference Include="$(SharedNativeRoot)libs\build-native.proj"
-                      AdditionalProperties="RuntimeFlavor=$(_NetCoreAppLibrariesRuntimeFlavor)"
+                      AdditionalProperties="RuntimeFlavor=$(LibrariesRuntimeFlavor)"
                       GlobalPropertiesToRemove="RuntimeIdentifier;TargetFramework"
                       ReferenceOutputAssembly="false"
                       SetConfiguration="Configuration=$(LibrariesConfiguration)"
                       SkipGetTargetFrameworkProperties="true" />
     <ProjectReference Include="$(LibrariesProjectRoot)sfx-src.proj"
-                      AdditionalProperties="RuntimeFlavor=$(_NetCoreAppLibrariesRuntimeFlavor)"
-                      GlobalPropertiesToRemove="RuntimeIdentifier;TargetFramework"
+                      AdditionalProperties="RuntimeFlavor=$(LibrariesRuntimeFlavor)"
+                      GlobalPropertiesToRemove="LibrariesRuntimeFlavor;RuntimeIdentifier;TargetFramework"
+                      OutputItemType="_NetCoreAppLibrarySourceAssembly"
                       ReferenceOutputAssembly="false"
                       SetConfiguration="Configuration=$(LibrariesConfiguration)"
-                      SkipGetTargetFrameworkProperties="true"
-                      OutputItemType="_NetCoreAppLibrarySourceAssembly" />
+                      SkipGetTargetFrameworkProperties="true" />
   </ItemGroup>
 
   <PropertyGroup>
@@ -52,7 +57,8 @@
     <_SymbolFilesToPackage Include="@(_HostSymbolFiles->Exists())" IsNative="true" />
   </ItemGroup>
 
-  <Target Name="AddRuntimeFilesToPackage" DependsOnTargets="ResolveRuntimeFilesFromLocalBuild">
+  <Target Name="AddRuntimeFilesToPackage"
+          DependsOnTargets="ResolveRuntimeFilesFromLocalBuild">
     <ItemGroup>
       <RuntimeFiles Condition="'%(RuntimeFiles.IsNative)' == 'true'">
         <TargetPath>runtimes/$(RuntimeIdentifier)/native</TargetPath>
diff --git a/src/libraries/Directory.Build.targets b/src/libraries/Directory.Build.targets
index dbe74e9c4c4330..b2de65daf1ac30 100644
--- a/src/libraries/Directory.Build.targets
+++ b/src/libraries/Directory.Build.targets
@@ -16,6 +16,11 @@
   <Import Project="$(RepositoryEngineeringDir)resources.targets" />
   <Import Project="..\..\Directory.Build.targets" />
 
+  <ItemGroup>
+    <ProjectReference Update="$(CoreLibProject)"
+                      GlobalPropertiesToRemove="LibrariesRuntimeFlavor;RuntimeFlavor" />
+  </ItemGroup>
+
   <PropertyGroup>
     <NETStandard21RefPath>$([MSBuild]::NormalizeDirectory('$(NuGetPackageRoot)', 'netstandard.library.ref', '$(NETStandardLibraryRefVersion)', 'ref', 'netstandard2.1'))</NETStandard21RefPath>
 
diff --git a/src/libraries/sfx-src.proj b/src/libraries/sfx-src.proj
index b2823831c9be8d..606a311cb54fd0 100644
--- a/src/libraries/sfx-src.proj
+++ b/src/libraries/sfx-src.proj
@@ -11,6 +11,8 @@
 
   <ItemGroup>
     <ProjectReference Include="@(NetCoreAppLibrarySourceProject)" />
+    <ProjectReference Update="$(CoreLibProject)"
+                      GlobalPropertiesToRemove="LibrariesRuntimeFlavor;RuntimeFlavor" />
   </ItemGroup>
 
 </Project>

From 397d037b63bb3a690f567fa655f4b58a0f01d4ee Mon Sep 17 00:00:00 2001
From: Jeremy Koritzinsky <jekoritz@microsoft.com>
Date: Tue, 8 Sep 2026 21:03:39 -0700
Subject: [PATCH 7/9] Preserve analyzer resource directories

Use a recursive generator resource glob and remove empty runtime pack item groups.

Co-authored-by: Copilot App <223556219+Copilot@users.noreply.github.com>

Copilot-Session: a02d8ce4-72ef-40df-b3d2-8bea5d31d7a4
---
 .../Microsoft.NETCore.App/Microsoft.NETCore.App.Ref.sfxproj    | 2 +-
 .../Microsoft.NETCore.App.Runtime.CoreCLR.sfxproj              | 3 ---
 .../Microsoft.NETCore.App.Runtime.Mono.sfxproj                 | 3 ---
 3 files changed, 1 insertion(+), 7 deletions(-)

diff --git a/src/installer/pkg/sfx/Microsoft.NETCore.App/Microsoft.NETCore.App.Ref.sfxproj b/src/installer/pkg/sfx/Microsoft.NETCore.App/Microsoft.NETCore.App.Ref.sfxproj
index 75bb3c07743fc6..25bd2ce691e0d9 100644
--- a/src/installer/pkg/sfx/Microsoft.NETCore.App/Microsoft.NETCore.App.Ref.sfxproj
+++ b/src/installer/pkg/sfx/Microsoft.NETCore.App/Microsoft.NETCore.App.Ref.sfxproj
@@ -33,7 +33,7 @@
     <ItemGroup>
       <_NetCoreAppRefPackGeneratorRelatedFile Include="@(_NetCoreAppRefPackGeneratorFile)" />
       <_NetCoreAppRefPackGeneratorRelatedFile Include="@(_NetCoreAppRefPackGeneratorFile->'%(RootDir)%(Directory)%(Filename).pdb')" />
-      <_NetCoreAppRefPackGeneratorRelatedFile Include="%(_NetCoreAppRefPackGeneratorFile.RootDir)%(_NetCoreAppRefPackGeneratorFile.Directory)*\%(_NetCoreAppRefPackGeneratorFile.Filename).resources.dll" />
+      <_NetCoreAppRefPackGeneratorRelatedFile Include="%(_NetCoreAppRefPackGeneratorFile.RootDir)%(_NetCoreAppRefPackGeneratorFile.Directory)**\%(_NetCoreAppRefPackGeneratorFile.Filename).resources.dll" />
       <_NetCoreAppRefPackGeneratorRelatedFile Remove="@(_NetCoreAppRefPackGeneratorRelatedFile)"
                                               Condition="!Exists('%(_NetCoreAppRefPackGeneratorRelatedFile.Identity)')" />
       <_NetCoreAppLibraryPublicSourceAssembly Include="@(_NetCoreAppLibrarySourceAssembly)"
diff --git a/src/installer/pkg/sfx/Microsoft.NETCore.App/Microsoft.NETCore.App.Runtime.CoreCLR.sfxproj b/src/installer/pkg/sfx/Microsoft.NETCore.App/Microsoft.NETCore.App.Runtime.CoreCLR.sfxproj
index 5a59bdc91218ae..3c83c187d1ca50 100644
--- a/src/installer/pkg/sfx/Microsoft.NETCore.App/Microsoft.NETCore.App.Runtime.CoreCLR.sfxproj
+++ b/src/installer/pkg/sfx/Microsoft.NETCore.App/Microsoft.NETCore.App.Runtime.CoreCLR.sfxproj
@@ -55,9 +55,6 @@
     <UseMibcProjectReference>true</UseMibcProjectReference>
   </PropertyGroup>
 
-  <ItemGroup>
-  </ItemGroup>
-
   <Target Name="AddCoreCLRRuntimeManagedFiles"
           BeforeTargets="AddRuntimeFilesToPackage"
           DependsOnTargets="ResolveProjectReferences">
diff --git a/src/installer/pkg/sfx/Microsoft.NETCore.App/Microsoft.NETCore.App.Runtime.Mono.sfxproj b/src/installer/pkg/sfx/Microsoft.NETCore.App/Microsoft.NETCore.App.Runtime.Mono.sfxproj
index 638a82e747177f..e8ec67e316f6df 100644
--- a/src/installer/pkg/sfx/Microsoft.NETCore.App/Microsoft.NETCore.App.Runtime.Mono.sfxproj
+++ b/src/installer/pkg/sfx/Microsoft.NETCore.App/Microsoft.NETCore.App.Runtime.Mono.sfxproj
@@ -50,9 +50,6 @@
     <UseRuntimeManagedProjectReferences>true</UseRuntimeManagedProjectReferences>
   </PropertyGroup>
 
-  <ItemGroup>
-  </ItemGroup>
-
   <Target Name="AddMonoCoreLibToRuntimeFiles"
           BeforeTargets="AddRuntimeFilesToPackage"
           DependsOnTargets="ResolveProjectReferences">

From ef67f50d05703ba636bf542bec988c5fc5c0d70d Mon Sep 17 00:00:00 2001
From: Jeremy Koritzinsky <jekoritz@microsoft.com>
Date: Mon, 14 Sep 2026 11:06:20 -0700
Subject: [PATCH 8/9] Use shared MIBc project reference condition

Let all runtime packs rely on the condition in codeOptimization.targets instead of forcing the project reference locally.

Co-authored-by: Copilot App <223556219+Copilot@users.noreply.github.com>

Copilot-Session: a02d8ce4-72ef-40df-b3d2-8bea5d31d7a4
---
 .../Microsoft.NETCore.App.Runtime.CoreCLR.sfxproj                | 1 -
 .../Microsoft.NETCore.App.Runtime.NativeAOT.sfxproj              | 1 -
 2 files changed, 2 deletions(-)

diff --git a/src/installer/pkg/sfx/Microsoft.NETCore.App/Microsoft.NETCore.App.Runtime.CoreCLR.sfxproj b/src/installer/pkg/sfx/Microsoft.NETCore.App/Microsoft.NETCore.App.Runtime.CoreCLR.sfxproj
index 3c83c187d1ca50..7986ee45ca5717 100644
--- a/src/installer/pkg/sfx/Microsoft.NETCore.App/Microsoft.NETCore.App.Runtime.CoreCLR.sfxproj
+++ b/src/installer/pkg/sfx/Microsoft.NETCore.App/Microsoft.NETCore.App.Runtime.CoreCLR.sfxproj
@@ -52,7 +52,6 @@
     <CoreLibConfiguration>$(CoreCLRConfiguration)</CoreLibConfiguration>
     <LibrariesRuntimeFlavor Condition="'$(LibrariesRuntimeFlavor)' == ''">CoreCLR</LibrariesRuntimeFlavor>
     <UseRuntimeManagedProjectReferences>true</UseRuntimeManagedProjectReferences>
-    <UseMibcProjectReference>true</UseMibcProjectReference>
   </PropertyGroup>
 
   <Target Name="AddCoreCLRRuntimeManagedFiles"
diff --git a/src/installer/pkg/sfx/Microsoft.NETCore.App/Microsoft.NETCore.App.Runtime.NativeAOT.sfxproj b/src/installer/pkg/sfx/Microsoft.NETCore.App/Microsoft.NETCore.App.Runtime.NativeAOT.sfxproj
index 738c684a9169e3..ba0ff5783e75f1 100644
--- a/src/installer/pkg/sfx/Microsoft.NETCore.App/Microsoft.NETCore.App.Runtime.NativeAOT.sfxproj
+++ b/src/installer/pkg/sfx/Microsoft.NETCore.App/Microsoft.NETCore.App.Runtime.NativeAOT.sfxproj
@@ -23,7 +23,6 @@
     <CoreLibProject>$([MSBuild]::NormalizePath('$(CoreClrProjectRoot)', 'nativeaot', 'System.Private.CoreLib', 'src', 'System.Private.CoreLib.csproj'))</CoreLibProject>
     <LibrariesRuntimeFlavor>CoreCLR</LibrariesRuntimeFlavor>
     <UseRuntimeManagedProjectReferences>true</UseRuntimeManagedProjectReferences>
-    <UseMibcProjectReference>true</UseMibcProjectReference>
   </PropertyGroup>
 
   <ItemGroup>

From e50c9cde708495ef6370fce66f82defe63e3dc2d Mon Sep 17 00:00:00 2001
From: Jeremy Koritzinsky <jekoritz@microsoft.com>
Date: Thu, 17 Sep 2026 11:11:51 -0700
Subject: [PATCH 9/9] Fix runtime pack CoreLib and MIBc inputs

Treat project-produced CoreLib as a native runtime-pack asset on every platform and include the merged MIBc project output in regular NativeAOT packs while keeping source-build excluded.

Co-authored-by: Copilot App <223556219+Copilot@users.noreply.github.com>

Copilot-Session: a02d8ce4-72ef-40df-b3d2-8bea5d31d7a4
---
 eng/codeOptimization.targets                                  | 4 ++--
 .../Microsoft.NETCore.App.Runtime.CoreCLR.sfxproj             | 3 ++-
 2 files changed, 4 insertions(+), 3 deletions(-)

diff --git a/eng/codeOptimization.targets b/eng/codeOptimization.targets
index f642bb21ceba0e..6eb04f19074f59 100644
--- a/eng/codeOptimization.targets
+++ b/eng/codeOptimization.targets
@@ -16,8 +16,8 @@
     <_MibcConfiguration Condition="'$(CoreCLRConfiguration)' == ''">$(Configuration)</_MibcConfiguration>
     <_MibcConfiguration Condition="'$(CoreCLRConfiguration)' != ''">$(CoreCLRConfiguration)</_MibcConfiguration>
     <UseMibcProjectReference Condition="'$(UseMibcProjectReference)' == '' and
-                                        '$(PublishReadyToRun)' == 'true' and
-                                        '$(DotNetBuildSourceOnly)' != 'true'">true</UseMibcProjectReference>
+                                        '$(DotNetBuildSourceOnly)' != 'true' and
+                                        ('$(PublishReadyToRun)' == 'true' or '$(BuildNativeAOTRuntimePack)' == 'true')">true</UseMibcProjectReference>
   </PropertyGroup>
 
   <ItemGroup Condition="'$(UseMibcProjectReference)' == 'true'">
diff --git a/src/installer/pkg/sfx/Microsoft.NETCore.App/Microsoft.NETCore.App.Runtime.CoreCLR.sfxproj b/src/installer/pkg/sfx/Microsoft.NETCore.App/Microsoft.NETCore.App.Runtime.CoreCLR.sfxproj
index 7986ee45ca5717..902b99a99d6d2b 100644
--- a/src/installer/pkg/sfx/Microsoft.NETCore.App/Microsoft.NETCore.App.Runtime.CoreCLR.sfxproj
+++ b/src/installer/pkg/sfx/Microsoft.NETCore.App/Microsoft.NETCore.App.Runtime.CoreCLR.sfxproj
@@ -58,7 +58,8 @@
           BeforeTargets="AddRuntimeFilesToPackage"
           DependsOnTargets="ResolveProjectReferences">
     <ItemGroup>
-      <RuntimeFiles Include="@(_RuntimeCoreLibFile)" />
+      <RuntimeFiles Include="@(_RuntimeCoreLibFile)"
+                    IsNative="true" />
     </ItemGroup>
   </Target>