Fix leak-on-exit of QSGRenderLoop::s_instance

s_instance is created with new and never deleted which causes several
destructors to never be called.

Task-number: QTBUG-35731
Change-Id: Icccb19186958f8bb74c5fd2b4b41165255debc46
Reviewed-by: Gunnar Sletta <gunnar.sletta@jollamobile.com>

2 files changed, 11 insertions, 13 deletions

diff --git a/src/quick/scenegraph/qsgrenderloop.cpp b/src/quick/scenegraph/qsgrenderloop.cpp
index ac1bdb7841..219f877bec 100644
--- a/src/quick/scenegraph/qsgrenderloop.cpp
+++ b/src/quick/scenegraph/qsgrenderloop.cpp
@@ -45,6 +45,7 @@
 
 #include <QtCore/QCoreApplication>
 #include <QtCore/QTime>
+#include <QtCore/QScopedPointer>
 #include <QtCore/private/qabstractanimation_p.h>
 
 #include <QtGui/QOpenGLContext>
@@ -76,7 +77,7 @@ extern Q_GUI_EXPORT QImage qt_gl_read_framebuffer(const QSize &size, bool alpha_
 DEFINE_BOOL_CONFIG_OPTION(qmlNoThreadedRenderer, QML_BAD_GUI_RENDER_LOOP);
 DEFINE_BOOL_CONFIG_OPTION(qmlForceThreadedRenderer, QML_FORCE_THREADED_RENDERER); // Might trigger graphics driver threading bugs, use at own risk
 
-QSGRenderLoop *QSGRenderLoop::s_instance = 0;
+Q_GLOBAL_STATIC(QScopedPointer<QSGRenderLoop>, s_renderLoopInstance);
 
 QSGRenderLoop::~QSGRenderLoop()
 {
@@ -142,8 +143,8 @@ bool QSGRenderLoop::useConsistentTiming()
 
 QSGRenderLoop *QSGRenderLoop::instance()
 {
-    if (!s_instance) {
-        s_instance = QSGContext::createWindowManager();
+    if (s_renderLoopInstance->isNull()) {
+        s_renderLoopInstance->reset(QSGContext::createWindowManager());
 
         bool info = qEnvironmentVariableIsSet("QSG_INFO");
 
@@ -153,7 +154,7 @@ QSGRenderLoop *QSGRenderLoop::instance()
                 qDebug() << "QSG: using fixed animation steps";
         }
 
-        if (!s_instance) {
+        if (s_renderLoopInstance->isNull()) {
 
             enum RenderLoopType {
                 BasicRenderLoop,
@@ -185,26 +186,26 @@ QSGRenderLoop *QSGRenderLoop::instance()
             switch (loopType) {
             case ThreadedRenderLoop:
                 if (info) qDebug() << "QSG: threaded render loop";
-                s_instance = new QSGThreadedRenderLoop();
+                s_renderLoopInstance->reset(new QSGThreadedRenderLoop());
                 break;
             case WindowsRenderLoop:
                 if (info) qDebug() << "QSG: windows render loop";
-                s_instance = new QSGWindowsRenderLoop();
+                s_renderLoopInstance->reset(new QSGWindowsRenderLoop());
                 break;
             default:
                 if (info) qDebug() << "QSG: basic render loop";
-                s_instance = new QSGGuiThreadRenderLoop();
+                s_renderLoopInstance->reset(new QSGGuiThreadRenderLoop());
                 break;
             }
         }
     }
-    return s_instance;
+    return s_renderLoopInstance->data();
 }
 
 void QSGRenderLoop::setInstance(QSGRenderLoop *instance)
 {
-    Q_ASSERT(!s_instance);
-    s_instance = instance;
+    Q_ASSERT(!s_renderLoopInstance);
+    s_renderLoopInstance->reset(instance);
 }
 
 QSGGuiThreadRenderLoop::QSGGuiThreadRenderLoop()
diff --git a/src/quick/scenegraph/qsgrenderloop_p.h b/src/quick/scenegraph/qsgrenderloop_p.h
index 72bad16c63..46edd77eda 100644
--- a/src/quick/scenegraph/qsgrenderloop_p.h
+++ b/src/quick/scenegraph/qsgrenderloop_p.h
@@ -88,9 +88,6 @@ public:
 
 Q_SIGNALS:
     void timeToIncubate();
-
-private:
-    static QSGRenderLoop *s_instance;
 };
 
 QT_END_NAMESPACE