Avoid illegal downcasts in texture and shader handling

Fixes bad type-cast during destruction when objects no longer has the
full type they used to.

Detected by UBSAN.

Change-Id: I4867091901d70d5a882656834eb97a704def1751
Reviewed-by: Simon Hausmann <simon.hausmann@qt.io>

1 files changed, 4 insertions, 4 deletions

diff --git a/src/quick/items/qquickopenglshadereffectnode.cpp b/src/quick/items/qquickopenglshadereffectnode.cpp
index f32b32491b..f96ebebcd6 100644
--- a/src/quick/items/qquickopenglshadereffectnode.cpp
+++ b/src/quick/items/qquickopenglshadereffectnode.cpp
@@ -477,11 +477,11 @@ void QQuickOpenGLShaderEffectMaterial::updateTextures() const
     }
 }
 
-void QQuickOpenGLShaderEffectMaterial::invalidateTextureProvider(QSGTextureProvider *provider)
+void QQuickOpenGLShaderEffectMaterial::invalidateTextureProvider(const QObject *provider)
 {
     for (int i = 0; i < textureProviders.size(); ++i) {
         if (provider == textureProviders.at(i))
-            textureProviders[i] = 0;
+            textureProviders[i] = nullptr;
     }
 }
 
@@ -505,10 +505,10 @@ void QQuickOpenGLShaderEffectNode::markDirtyTexture()
     Q_EMIT dirtyTexture();
 }
 
-void QQuickOpenGLShaderEffectNode::textureProviderDestroyed(QObject *object)
+void QQuickOpenGLShaderEffectNode::textureProviderDestroyed(const QObject *object)
 {
     Q_ASSERT(material());
-    static_cast<QQuickOpenGLShaderEffectMaterial *>(material())->invalidateTextureProvider(static_cast<QSGTextureProvider *>(object));
+    static_cast<QQuickOpenGLShaderEffectMaterial *>(material())->invalidateTextureProvider(object);
 }
 
 void QQuickOpenGLShaderEffectNode::preprocess()