2 files changed, 13 insertions, 1 deletions
diff --git a/src/plugins/directshow/directshow.pro b/src/plugins/directshow/directshow.pro
index 2857f87d9..54d617166 100644
--- a/src/plugins/directshow/directshow.pro
+++ b/src/plugins/directshow/directshow.pro
@@ -8,7 +8,13 @@ win32:!qtHaveModule(opengl)|qtConfig(dynamicgl) {
 HEADERS += dsserviceplugin.h
 SOURCES += dsserviceplugin.cpp
 
-mingw: DEFINES += NO_DSHOW_STRSAFE
+# Remove WINVER/_WIN32_WINNT definitions added to qt_build_config.prf
+# by qtbase/d57a7c41712f8627a462d893329dc3f0dbb52d32 since the multimedia
+# headers of MinGW 5.3/7.1 are too broken to compile with 0x0601.
+mingw {
+    DEFINES -= WINVER=0x0601 _WIN32_WINNT=0x0601
+    DEFINES += NO_DSHOW_STRSAFE
+}
 
 include(common/common.pri)
 qtConfig(directshow-player): include(player/player.pri)
diff --git a/src/plugins/directshow/dsserviceplugin.cpp b/src/plugins/directshow/dsserviceplugin.cpp
index 51be7e500..cb4f0cdf9 100644
--- a/src/plugins/directshow/dsserviceplugin.cpp
+++ b/src/plugins/directshow/dsserviceplugin.cpp
@@ -123,7 +123,9 @@ QMediaServiceProviderHint::Features DSServicePlugin::supportedFeatures(
 QByteArray DSServicePlugin::defaultDevice(const QByteArray &service) const
 {
     if (service == Q_MEDIASERVICE_CAMERA) {
+        addRefCount();
         const QList<DSVideoDeviceInfo> &devs = DSVideoDeviceControl::availableDevices();
+        releaseRefCount();
         if (!devs.isEmpty())
             return devs.first().first;
     }
@@ -135,7 +137,9 @@ QList<QByteArray> DSServicePlugin::devices(const QByteArray &service) const
     QList<QByteArray> result;
 
     if (service == Q_MEDIASERVICE_CAMERA) {
+        addRefCount();
         const QList<DSVideoDeviceInfo> &devs = DSVideoDeviceControl::availableDevices();
+        releaseRefCount();
         for (const DSVideoDeviceInfo &info : devs)
             result.append(info.first);
     }
@@ -146,7 +150,9 @@ QList<QByteArray> DSServicePlugin::devices(const QByteArray &service) const
 QString DSServicePlugin::deviceDescription(const QByteArray &service, const QByteArray &device)
 {
     if (service == Q_MEDIASERVICE_CAMERA) {
+        addRefCount();
         const QList<DSVideoDeviceInfo> &devs = DSVideoDeviceControl::availableDevices();
+        releaseRefCount();
         for (const DSVideoDeviceInfo &info : devs) {
             if (info.first == device)
                 return info.second;