Add sanity check to WeakPointer.

We assume that the shared pointer can never be freed before the data
holding the weak reference, so make that explicit in the code.

Change-Id: Ieced69d09d66c3dbc5d91f1ca905048b271c24df
Reviewed-by: Joerg Bornemann <joerg.bornemann@digia.com>

1 files changed, 10 insertions, 3 deletions

diff --git a/src/lib/tools/weakpointer.h b/src/lib/tools/weakpointer.h
index f50f3d78f..4c851f655 100644
--- a/src/lib/tools/weakpointer.h
+++ b/src/lib/tools/weakpointer.h
@@ -40,9 +40,16 @@ public:
     WeakPointer() : QWeakPointer<T>() {}
     WeakPointer(const QSharedPointer<T> &sharedPointer) : QWeakPointer<T>(sharedPointer) {}
 
-    operator T*() const { return QWeakPointer<T>::data(); }
-    T *operator->() const { return QWeakPointer<T>::data(); }
-    T operator*() const { return *QWeakPointer<T>::data(); }
+    operator T*() const { return checkedData(); }
+    T *operator->() const { return checkedData(); }
+    T operator*() const { return *checkedData(); }
+
+private:
+    T *checkedData() const {
+        T * const d = QWeakPointer<T>::data();
+        Q_ASSERT(d); // Calling code is not expecting this situation.
+        return d;
+    }
 };
 
 } // namespace Internal