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, 2 insertions, 2 deletions

diff --git a/src/quick/items/qquickopenglshadereffectnode_p.h b/src/quick/items/qquickopenglshadereffectnode_p.h
index 7c75bb3126..6d68ba87b9 100644
--- a/src/quick/items/qquickopenglshadereffectnode_p.h
+++ b/src/quick/items/qquickopenglshadereffectnode_p.h
@@ -122,7 +122,7 @@ public:
 
     void setProgramSource(const QQuickOpenGLShaderEffectMaterialKey &source);
     void updateTextures() const;
-    void invalidateTextureProvider(QSGTextureProvider *provider);
+    void invalidateTextureProvider(const QObject *provider);
 
     static void cleanupMaterialCache();
 
@@ -159,7 +159,7 @@ Q_SIGNALS:
 
 private Q_SLOTS:
     void markDirtyTexture();
-    void textureProviderDestroyed(QObject *object);
+    void textureProviderDestroyed(const QObject *object);
 };
 
 QT_END_NAMESPACE