From 4391213ac17efab6c78c6477f7a2394bb04d6a8c Mon Sep 17 00:00:00 2001
From: Sven Boemer <sbomer@gmail.com>
Date: Mon, 28 Aug 2023 12:53:30 -0700
Subject: [PATCH] Prevent restore from deleting mibc cache file (#91220)

Restore should not remove the mibc cache file that is
used to enable incrementalism when merging mibc files.

This fixes an issue with the logic introduced in
454057de49d9e2ab337f808e1f65d1dda8dbe71a, which
was tested on incremental builds without restore.
---
 eng/restore/optimizationData.targets | 7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/eng/restore/optimizationData.targets b/eng/restore/optimizationData.targets
index 4d6b773bf201..009d6c8bca1e 100644
--- a/eng/restore/optimizationData.targets
+++ b/eng/restore/optimizationData.targets
@@ -1,4 +1,4 @@
-<Project>
+<Project>
   <ItemGroup>
     <!-- Mibc data to use when exact architecture match is available -->
     <MIBCPackageDef Include="optimization.windows_nt-x86.mibc.runtime" Version="$(optimizationwindows_ntx86MIBCRuntimeVersion)" MibcArchitecture="windows/x86"/>
@@ -25,6 +25,9 @@
   <Target Name="GetMIBCData"
           AfterTargets="Restore">
 
+    <PropertyGroup>
+      <_MergeMibcFilesCacheFile>$(MibcOptimizationDataDir)/$(TargetOS)/$(TargetArchitecture)/merge_mibc_files.cache</_MergeMibcFilesCacheFile>
+    </PropertyGroup>
     <ItemGroup>
       <MIBCPackage>
         <PackagePath>$(NuGetPackageRoot)%(MIBCPackage.Identity)/%(MIBCPackage.Version)</PackagePath>
@@ -32,7 +35,7 @@
       <_optimizationMibcFile Include="%(MIBCPackage.PackagePath)/**/*.mibc" SubdirectoryName="$(TargetOS)/$(TargetArchitecture)" />
       <_optimizationMibcDestinationFile Include="@(_optimizationMibcFile->'$(MibcOptimizationDataDir)%(SubdirectoryName)/%(RecursiveDir)%(Filename)%(Extension)')" />
       <ExcessFilesCurrentlyPresent Include="$(MibcOptimizationDataDir)/**" 
-                                   Exclude="@(_optimizationMibcDestinationFile)"/>
+                                   Exclude="@(_optimizationMibcDestinationFile);$(_MergeMibcFilesCacheFile)"/>
     </ItemGroup>
 
     <Error Condition="'@(_optimizationMibcFile)' == ''" Text="Failed to restore Mibc optimization data" />