5 files changed, 113 insertions, 1 deletions
diff --git a/src/corelib/CMakeLists.txt b/src/corelib/CMakeLists.txt
index f9c5690037..f583d3180c 100644
--- a/src/corelib/CMakeLists.txt
+++ b/src/corelib/CMakeLists.txt
@@ -1015,6 +1015,12 @@ qt_internal_extend_target(Core CONDITION ANDROID
         platform/android/qandroidnativeinterface.cpp
 )
 
+qt_internal_extend_target(Core CONDITION WIN32
+    SOURCES
+        platform/windows/qfactorycacheregistration_p.h
+        platform/windows/qfactorycacheregistration.cpp
+)
+
 qt_internal_extend_target(Core CONDITION HAIKU AND NOT ANDROID
     SOURCES
         io/qstandardpaths_haiku.cpp
diff --git a/src/corelib/configure.cmake b/src/corelib/configure.cmake
index 5563729a5b..a8d6037a7d 100644
--- a/src/corelib/configure.cmake
+++ b/src/corelib/configure.cmake
@@ -746,7 +746,7 @@ qt_feature("xmlstream" PUBLIC
     LABEL "XML Streaming APIs"
     PURPOSE "Provides a simple streaming API for XML."
 )
-qt_feature("cpp-winrt" PRIVATE
+qt_feature("cpp-winrt" PRIVATE PUBLIC
     LABEL "cpp/winrt base"
     PURPOSE "basic cpp/winrt language projection support"
     CONDITION WIN32 AND TEST_cpp_winrt
diff --git a/src/corelib/platform/windows/qfactorycacheregistration.cpp b/src/corelib/platform/windows/qfactorycacheregistration.cpp
new file mode 100644
index 0000000000..6bd69c66d1
--- /dev/null
+++ b/src/corelib/platform/windows/qfactorycacheregistration.cpp
@@ -0,0 +1,53 @@
+// Copyright (C) 2022 The Qt Company Ltd.
+// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR LGPL-3.0-only OR GPL-2.0-only OR GPL-3.0-only
+
+#include "qfactorycacheregistration_p.h"
+
+#include <QtCore/QMutex>
+
+QT_BEGIN_NAMESPACE
+
+#ifdef QT_USE_FACTORY_CACHE_REGISTRATION
+
+static QBasicMutex registrationMutex;
+static detail::QWinRTFactoryCacheRegistration *firstElement;
+
+detail::QWinRTFactoryCacheRegistration::QWinRTFactoryCacheRegistration(
+        QFunctionPointer clearFunction)
+    : m_clearFunction(clearFunction)
+{
+    QMutexLocker lock(&registrationMutex);
+
+    // forward pointers
+    m_next = std::exchange(firstElement, this);
+
+    // backward pointers
+    m_prevNext = &firstElement;
+    if (m_next)
+        m_next->m_prevNext = &m_next;
+}
+
+detail::QWinRTFactoryCacheRegistration::~QWinRTFactoryCacheRegistration()
+{
+    QMutexLocker lock(&registrationMutex);
+
+    *m_prevNext = m_next;
+
+    if (m_next)
+        m_next->m_prevNext = m_prevNext;
+}
+
+void detail::QWinRTFactoryCacheRegistration::clearAllCaches()
+{
+    QMutexLocker lock(&registrationMutex);
+
+    detail::QWinRTFactoryCacheRegistration *element;
+
+    for (element = firstElement; element != nullptr; element = element->m_next) {
+        element->m_clearFunction();
+    }
+}
+
+#endif
+
+QT_END_NAMESPACE
diff --git a/src/corelib/platform/windows/qfactorycacheregistration_p.h b/src/corelib/platform/windows/qfactorycacheregistration_p.h
new file mode 100644
index 0000000000..db1582e94b
--- /dev/null
+++ b/src/corelib/platform/windows/qfactorycacheregistration_p.h
@@ -0,0 +1,52 @@
+// Copyright (C) 2022 The Qt Company Ltd.
+// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR LGPL-3.0-only OR GPL-2.0-only OR GPL-3.0-only
+
+#ifndef QFACTORYCACHEREGISTRATION_P_H
+#define QFACTORYCACHEREGISTRATION_P_H
+
+//
+//  W A R N I N G
+//  -------------
+//
+// This file is not part of the Qt API.  It exists purely as an
+// implementation detail.  This header file may change from version to
+// version without notice, or even be removed.
+//
+// We mean it.
+//
+
+#include <QtCore/qglobal.h>
+
+#if !defined(QT_BOOTSTRAPPED) && defined(Q_OS_WIN) && !defined(Q_CC_CLANG) && QT_CONFIG(cpp_winrt)
+#    define QT_USE_FACTORY_CACHE_REGISTRATION
+#endif
+
+#ifdef QT_USE_FACTORY_CACHE_REGISTRATION
+
+#include <winrt/base.h>
+
+QT_BEGIN_NAMESPACE
+
+namespace detail {
+
+class QWinRTFactoryCacheRegistration
+{
+public:
+    Q_CORE_EXPORT explicit QWinRTFactoryCacheRegistration(QFunctionPointer clearFunction);
+    Q_CORE_EXPORT ~QWinRTFactoryCacheRegistration();
+    Q_CORE_EXPORT static void clearAllCaches();
+
+    Q_DISABLE_COPY_MOVE(QWinRTFactoryCacheRegistration)
+private:
+    QWinRTFactoryCacheRegistration **m_prevNext = nullptr;
+    QWinRTFactoryCacheRegistration *m_next = nullptr;
+    QFunctionPointer m_clearFunction;
+};
+
+inline QWinRTFactoryCacheRegistration reg([]() noexcept { winrt::clear_factory_cache(); });
+}
+
+QT_END_NAMESPACE
+
+#endif
+#endif // QFACTORYCACHEREGISTRATION_P_H
diff --git a/src/corelib/text/qlocale_win.cpp b/src/corelib/text/qlocale_win.cpp
index 3a3ae443c6..821369ff89 100644
--- a/src/corelib/text/qlocale_win.cpp
+++ b/src/corelib/text/qlocale_win.cpp
@@ -21,6 +21,7 @@
 
 #if QT_CONFIG(cpp_winrt)
 #   include <winrt/base.h>
+#   include <QtCore/private/qfactorycacheregistration_p.h>
 // Workaround for Windows SDK bug.
 // See https://github.com/microsoft/Windows.UI.Composition-Win32-Samples/issues/47
 namespace winrt::impl