diff --git a/.github/workflows/update-status-chart.yml b/.github/workflows/update-status-chart.yml
index 9cb6c3e1a4e..ac8a5896680 100644
--- a/.github/workflows/update-status-chart.yml
+++ b/.github/workflows/update-status-chart.yml
@@ -14,7 +14,7 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - name: Checkout gh-pages
-        uses: actions/checkout@v5
+        uses: actions/checkout@v6
         with:
           ref: gh-pages
       - name: Setup Node.js
diff --git a/CMakeLists.txt b/CMakeLists.txt
index a1546ccf872..c9ba52f1857 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -6,8 +6,8 @@ cmake_minimum_required(VERSION 4.1.1)
 set(CMAKE_TRY_COMPILE_TARGET_TYPE STATIC_LIBRARY)
 project(msvc_standard_libraries LANGUAGES CXX)
 
-if(CMAKE_CXX_COMPILER_VERSION VERSION_LESS "19.50.35719")
-    message(FATAL_ERROR "The STL must be built with MSVC Compiler 19.50.35719 or later.")
+if(CMAKE_CXX_COMPILER_VERSION VERSION_LESS "19.50.35720")
+    message(FATAL_ERROR "The STL must be built with MSVC Compiler 19.50.35720 or later.")
 endif()
 
 include(CheckCXXSourceCompiles)
diff --git a/azure-devops/config.yml b/azure-devops/config.yml
index 2c6fd986603..91a4aaae7fc 100644
--- a/azure-devops/config.yml
+++ b/azure-devops/config.yml
@@ -5,10 +5,10 @@
 
 variables:
 - name: poolName
-  value: 'Stl-2025-11-24T1624-x64-Pool'
+  value: 'Stl-2025-12-09T1433-x64-Pool'
   readonly: true
 - name: arm64PoolName
-  value: 'Stl-2025-11-24T1624-arm64-Pool'
+  value: 'Stl-2025-12-09T1433-arm64-Pool'
   readonly: true
 - name: poolDemands
   value: 'EnableSpotVM -equals false'
diff --git a/azure-devops/create-1es-hosted-pool.ps1 b/azure-devops/create-1es-hosted-pool.ps1
index 9a00ad3c3f4..0c475763b61 100644
--- a/azure-devops/create-1es-hosted-pool.ps1
+++ b/azure-devops/create-1es-hosted-pool.ps1
@@ -31,7 +31,7 @@ if ($Arch -ieq 'x64') {
 } else {
   # CPP_STL_GitHub has quota for 672 cores (21 VMs) in westcentralus, not currently used.
   $AvailableLocations = @('eastus2', 'northeurope') # Locations where CPP_STL_GitHub has quota for 1024 cores (32 VMs).
-  $AvailableLocationIdx = 2 # Increment for each new pool, to cycle through the available locations.
+  $AvailableLocationIdx = 3 # Increment for each new pool, to cycle through the available locations.
   $Location = $AvailableLocations[$AvailableLocationIdx % $AvailableLocations.Length]
   $VMSize = 'Standard_D32ps_v6'
   $PoolSize = 32
diff --git a/llvm-project b/llvm-project
index b725bdba1fa..27651133e21 160000
--- a/llvm-project
+++ b/llvm-project
@@ -1 +1 @@
-Subproject commit b725bdba1faf256c725f5fd12c581acb381bf0d3
+Subproject commit 27651133e213a6a1eb4d0e47837625cee3613111
diff --git a/tests/libcxx/expected_results.txt b/tests/libcxx/expected_results.txt
index af5b3060adb..171c3869c57 100644
--- a/tests/libcxx/expected_results.txt
+++ b/tests/libcxx/expected_results.txt
@@ -1001,6 +1001,9 @@ std/containers/sequences/vector/trivial_relocation.pass.cpp:1 FAIL
 # Not analyzed, likely bogus test. constexpr fails with "vector iterators incompatible".
 std/ranges/range.adaptors/range.join.with/range.join.with.iterator/ctor.default.pass.cpp FAIL
 
+# Test uses std::to_string() without including <string>.
+std/localization/locale.categories/category.numeric/locale.num.get/facet.num.get.members/get_long.pass.cpp FAIL
+
 
 # *** LIKELY STL BUGS ***
 # Not analyzed, likely STL bugs. Various assertions.