From 28d976be941e3bdb88fee5cdb504699e70b76c92 Mon Sep 17 00:00:00 2001
From: Vladimir Morozov <vmorozov@microsoft.com>
Date: Fri, 20 Dec 2024 12:24:00 -0800
Subject: [PATCH 1/2] Fix calls to std::mutex::lock

---
 vnext/PropertySheets/React.Cpp.props | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/vnext/PropertySheets/React.Cpp.props b/vnext/PropertySheets/React.Cpp.props
index 7a3557bddb2..ba4b1d9e470 100644
--- a/vnext/PropertySheets/React.Cpp.props
+++ b/vnext/PropertySheets/React.Cpp.props
@@ -66,6 +66,12 @@
       <PreprocessorDefinitions Condition="'$(UseV8)'=='true'">USE_V8;%(PreprocessorDefinitions)</PreprocessorDefinitions>
       <PreprocessorDefinitions Condition="'$(UseFabric)'=='true'">USE_FABRIC;%(PreprocessorDefinitions)</PreprocessorDefinitions>
       <PreprocessorDefinitions>JSI_VERSION=11;%(PreprocessorDefinitions)</PreprocessorDefinitions>
+      <!--
+        To address the crash on the first call to std::mutex::lock.
+        See: https://github.com/microsoft/STL/wiki/Changelog#vs-2022-1710
+             https://stackoverflow.com/questions/78598141/first-stdmutexlock-crashes-in-application-built-with-latest-visual-studio
+      -->
+      <PreprocessorDefinitions>_DISABLE_CONSTEXPR_MUTEX_CONSTRUCTOR;%(PreprocessorDefinitions)</PreprocessorDefinitions>
     </ClCompile>
   </ItemDefinitionGroup>
 

From d31268da0553751d073899bef06c4331cd01488f Mon Sep 17 00:00:00 2001
From: Vladimir Morozov <vmorozov@microsoft.com>
Date: Fri, 20 Dec 2024 12:24:16 -0800
Subject: [PATCH 2/2] Change files

---
 ...ative-windows-6fdddb9a-d20b-48fd-b2e0-73cb4aab35c5.json | 7 +++++++
 1 file changed, 7 insertions(+)
 create mode 100644 change/react-native-windows-6fdddb9a-d20b-48fd-b2e0-73cb4aab35c5.json

diff --git a/change/react-native-windows-6fdddb9a-d20b-48fd-b2e0-73cb4aab35c5.json b/change/react-native-windows-6fdddb9a-d20b-48fd-b2e0-73cb4aab35c5.json
new file mode 100644
index 00000000000..cfc2fd79283
--- /dev/null
+++ b/change/react-native-windows-6fdddb9a-d20b-48fd-b2e0-73cb4aab35c5.json
@@ -0,0 +1,7 @@
+{
+  "type": "prerelease",
+  "comment": "Fix calls to std::mutex::lock",
+  "packageName": "react-native-windows",
+  "email": "vmorozov@microsoft.com",
+  "dependentChangeType": "patch"
+}