From 29fe750fc940ce977efef2d8c35ce02950db074a Mon Sep 17 00:00:00 2001
From: Stenzek <stenzek@gmail.com>
Date: Fri, 9 Oct 2026 18:31:16 +1000
Subject: [PATCH] MSBuild: Improve reproducibility

Pin mtime of rcc timestamps.
---
 dep/vsprops/Base.props      |  5 ++++-
 dep/vsprops/QtCompile.props | 21 ++++++++++++++++++++-
 2 files changed, 24 insertions(+), 2 deletions(-)

diff --git a/dep/vsprops/Base.props b/dep/vsprops/Base.props
index e8467e7c7..77612b14f 100644
--- a/dep/vsprops/Base.props
+++ b/dep/vsprops/Base.props
@@ -41,7 +41,7 @@
       <ExceptionHandling>false</ExceptionHandling>
       <RuntimeTypeInfo>false</RuntimeTypeInfo>
       <AdditionalOptions Condition="$(Configuration.Contains(Clang))">/clang:-fno-rtti %(AdditionalOptions)</AdditionalOptions>
-      <AdditionalOptions Condition="!$(Configuration.Contains(Clang)) And $(Configuration.Contains(ReleaseLTCG))">/d1trimfile:&quot;$(SolutionDir)\&quot; %(AdditionalOptions)</AdditionalOptions>
+      <AdditionalOptions Condition="!$(Configuration.Contains(Clang)) And $(Configuration.Contains(ReleaseLTCG))">/d1trimfile:&quot;$(SolutionDir)\&quot; /Brepro %(AdditionalOptions)</AdditionalOptions>
       <AdditionalOptions Condition="$(Configuration.Contains(Clang)) And $(Configuration.Contains(ReleaseLTCG))">/clang:-ffile-prefix-map=&quot;$(SolutionDir)\&quot;= %(AdditionalOptions)</AdditionalOptions>
     </ClCompile>
     <Link>
@@ -49,6 +49,9 @@
       <AdditionalLibraryDirectories>%(AdditionalLibraryDirectories);$(DepsLibDir)</AdditionalLibraryDirectories>
       <AdditionalOptions Condition="$(Configuration.Contains(ReleaseLTCG))">/PDBALTPATH:%_PDB% /Brepro %(AdditionalOptions)</AdditionalOptions>
     </Link>
+    <Lib>
+      <AdditionalOptions Condition="!$(Configuration.Contains(Clang)) And $(Configuration.Contains(ReleaseLTCG))">/Brepro %(AdditionalOptions)</AdditionalOptions>
+    </Lib>
   </ItemDefinitionGroup>
 
   <ItemDefinitionGroup Condition="$(Configuration.Contains(Debug))">
diff --git a/dep/vsprops/QtCompile.props b/dep/vsprops/QtCompile.props
index 9ac85483e..1c120c220 100644
--- a/dep/vsprops/QtCompile.props
+++ b/dep/vsprops/QtCompile.props
@@ -100,7 +100,26 @@
       <Output TaskParameter="OutOfDateSources" ItemName="_QtResourceOutOfDate" />
     </GetOutOfDateItems>
     <Message Condition="'@(_QtResourceOutOfDate)'!=''" Text="rcc %(_QtResourceOutOfDate.Filename)" Importance="High" />
-    <Exec Condition="'@(_QtResourceOutOfDate)'!=''" Command="%(_QtResourceOutOfDate.Command)" />
+    <!-- rcc stamps every entry with the mtime of its source file, i.e. the checkout time. Pin it to the commit date instead. -->
+    <Exec
+      Condition="'@(_QtResourceOutOfDate)'!='' And '$(SOURCE_DATE_EPOCH)'==''"
+      Command="git -C &quot;$(SolutionDir).&quot; log -1 --format=%25%25ct"
+      ConsoleToMSBuild="true"
+      IgnoreExitCode="true"
+      IgnoreStandardErrorWarningFormat="true"
+      StandardOutputImportance="Low"
+      StandardErrorImportance="Low">
+      <Output TaskParameter="ConsoleOutput" PropertyName="_QtResourceCommitDate" />
+      <Output TaskParameter="ExitCode" PropertyName="_QtResourceCommitDateExitCode" />
+    </Exec>
+    <PropertyGroup>
+      <_QtResourceSourceDate>$(SOURCE_DATE_EPOCH)</_QtResourceSourceDate>
+      <_QtResourceSourceDate Condition="'$(_QtResourceSourceDate)'=='' And '$(_QtResourceCommitDateExitCode)'=='0'">$(_QtResourceCommitDate)</_QtResourceSourceDate>
+    </PropertyGroup>
+    <Exec
+      Condition="'@(_QtResourceOutOfDate)'!=''"
+      Command="%(_QtResourceOutOfDate.Command)"
+      EnvironmentVariables="SOURCE_DATE_EPOCH=$(_QtResourceSourceDate)" />
     <ItemGroup>
       <_QtResourceOutOfDate Remove="@(_QtResourceOutOfDate)" />
       <_QtResourceDependency Remove="@(_QtResourceDependency)" />