6 files changed, 22 insertions, 6 deletions
diff --git a/src/quick/items/qquickopenglshadereffect.cpp b/src/quick/items/qquickopenglshadereffect.cpp
index 76cb3ace5c..3aa00340b2 100644
--- a/src/quick/items/qquickopenglshadereffect.cpp
+++ b/src/quick/items/qquickopenglshadereffect.cpp
@@ -221,7 +221,7 @@ QQuickOpenGLShaderEffectCommon::~QQuickOpenGLShaderEffectCommon()
         clearSignalMappers(shaderType);
 }
 
-void QQuickOpenGLShaderEffectCommon::disconnectPropertySignals(QObject *obj, Key::ShaderType shaderType)
+void QQuickOpenGLShaderEffectCommon::disconnectPropertySignals(QQuickItem *item, Key::ShaderType shaderType)
 {
     for (int i = 0; i < uniformData[shaderType].size(); ++i) {
         if (signalMappers[shaderType].at(i) == 0)
@@ -229,11 +229,12 @@ void QQuickOpenGLShaderEffectCommon::disconnectPropertySignals(QObject *obj, Key
         const UniformData &d = uniformData[shaderType].at(i);
         auto mapper = signalMappers[shaderType].at(i);
         void *a = mapper;
-        QObjectPrivate::disconnect(obj, mapper->signalIndex(), &a);
+        QObjectPrivate::disconnect(item, mapper->signalIndex(), &a);
         if (d.specialType == UniformData::Sampler || d.specialType == UniformData::SamplerExternal) {
             QQuickItem *source = qobject_cast<QQuickItem *>(qvariant_cast<QObject *>(d.value));
             if (source) {
-                QQuickItemPrivate::get(source)->derefWindow();
+                if (item->window())
+                    QQuickItemPrivate::get(source)->derefWindow();
                 QObject::disconnect(source, SIGNAL(destroyed(QObject*)), host, SLOT(sourceDestroyed(QObject*)));
             }
         }
diff --git a/src/quick/items/qquickopenglshadereffect_p.h b/src/quick/items/qquickopenglshadereffect_p.h
index 3087c1eb0b..0c2adadc62 100644
--- a/src/quick/items/qquickopenglshadereffect_p.h
+++ b/src/quick/items/qquickopenglshadereffect_p.h
@@ -89,7 +89,7 @@ struct Q_QUICK_PRIVATE_EXPORT QQuickOpenGLShaderEffectCommon
 
     ~QQuickOpenGLShaderEffectCommon();
 
-    void disconnectPropertySignals(QObject *item, Key::ShaderType shaderType);
+    void disconnectPropertySignals(QQuickItem *item, Key::ShaderType shaderType);
     void connectPropertySignals(QQuickItem *item, const QMetaObject *itemMetaObject, Key::ShaderType shaderType);
     void updateParseLog(bool ignoreAttributes);
     void lookThroughShaderCode(QQuickItem *item, const QMetaObject *itemMetaObject, Key::ShaderType shaderType, const QByteArray &code);
diff --git a/src/quick/items/qquickopenglshadereffectnode.cpp b/src/quick/items/qquickopenglshadereffectnode.cpp
index f96ebebcd6..3ccd2a76f7 100644
--- a/src/quick/items/qquickopenglshadereffectnode.cpp
+++ b/src/quick/items/qquickopenglshadereffectnode.cpp
@@ -505,7 +505,7 @@ void QQuickOpenGLShaderEffectNode::markDirtyTexture()
     Q_EMIT dirtyTexture();
 }
 
-void QQuickOpenGLShaderEffectNode::textureProviderDestroyed(const QObject *object)
+void QQuickOpenGLShaderEffectNode::textureProviderDestroyed(QObject *object)
 {
     Q_ASSERT(material());
     static_cast<QQuickOpenGLShaderEffectMaterial *>(material())->invalidateTextureProvider(object);
diff --git a/src/quick/items/qquickopenglshadereffectnode_p.h b/src/quick/items/qquickopenglshadereffectnode_p.h
index 6d68ba87b9..705b8d4f47 100644
--- a/src/quick/items/qquickopenglshadereffectnode_p.h
+++ b/src/quick/items/qquickopenglshadereffectnode_p.h
@@ -159,7 +159,7 @@ Q_SIGNALS:
 
 private Q_SLOTS:
     void markDirtyTexture();
-    void textureProviderDestroyed(const QObject *object);
+    void textureProviderDestroyed(QObject *object);
 };
 
 QT_END_NAMESPACE
diff --git a/src/quick/items/qquickshadereffect.cpp b/src/quick/items/qquickshadereffect.cpp
index 05d9e5e36d..3721731f68 100644
--- a/src/quick/items/qquickshadereffect.cpp
+++ b/src/quick/items/qquickshadereffect.cpp
@@ -515,6 +515,20 @@ QQuickShaderEffect::QQuickShaderEffect(QQuickItem *parent)
         m_impl = new QQuickGenericShaderEffect(this, this);
 }
 
+QQuickShaderEffect::~QQuickShaderEffect()
+{
+    // Delete the implementations now, while they still have have
+    // valid references back to us.
+#if QT_CONFIG(opengl)
+    auto *glImpl = m_glImpl;
+    m_glImpl = nullptr;
+    delete glImpl;
+#endif
+    auto *impl = m_impl;
+    m_impl = nullptr;
+    delete impl;
+}
+
 /*!
     \qmlproperty string QtQuick::ShaderEffect::fragmentShader
 
diff --git a/src/quick/items/qquickshadereffect_p.h b/src/quick/items/qquickshadereffect_p.h
index cabad930fc..c5bddc40d2 100644
--- a/src/quick/items/qquickshadereffect_p.h
+++ b/src/quick/items/qquickshadereffect_p.h
@@ -92,6 +92,7 @@ public:
     Q_ENUM(Status)
 
     QQuickShaderEffect(QQuickItem *parent = nullptr);
+    ~QQuickShaderEffect() override;
 
     QByteArray fragmentShader() const;
     void setFragmentShader(const QByteArray &code);