Fix crash on object destruction

2 files changed, 15 insertions, 5 deletions

diff --git a/src/declarative/qml/qmlbasicscript.cpp b/src/declarative/qml/qmlbasicscript.cpp
index 478491f..d6d6625 100644
--- a/src/declarative/qml/qmlbasicscript.cpp
+++ b/src/declarative/qml/qmlbasicscript.cpp
@@ -181,6 +181,9 @@ static QVariant toObjectOrVariant(const QVariant &v)
 
 static QVariant fetch_value(QObject *o, int idx, int type)
 {
+    if (!o)
+        return QVariant();
+
     switch(type) {
         case QVariant::String:
             {
@@ -823,7 +826,7 @@ QVariant QmlBasicScript::run(QmlContext *context, void *voidCache, CacheState *c
                 QObject *obj = contextPrivate->defaultObjects.at(0);
 
                 stack.push(fetch_value(obj, instr.constant.idx, instr.constant.type));
-                if (instr.constant.notify != 0)
+                if (obj && instr.constant.notify != 0)
                     enginePrivate->capturedProperties <<
                         QmlEnginePrivate::CapturedProperty(obj, instr.constant.idx, instr.constant.notify); 
                 state = Reset;
@@ -835,7 +838,7 @@ QVariant QmlBasicScript::run(QmlContext *context, void *voidCache, CacheState *c
                 QObject *obj = contextPrivate->defaultObjects.at(1);
 
                 stack.push(fetch_value(obj, instr.constant.idx, instr.constant.type));
-                if (instr.constant.notify != 0)
+                if (obj && instr.constant.notify != 0)
                     enginePrivate->capturedProperties <<
                         QmlEnginePrivate::CapturedProperty(obj, instr.constant.idx, instr.constant.notify); 
                 state = Reset;
@@ -848,7 +851,7 @@ QVariant QmlBasicScript::run(QmlContext *context, void *voidCache, CacheState *c
                 QObject *obj = qvariant_cast<QObject *>(o);
 
                 stack.push(fetch_value(obj, instr.constant.idx, instr.constant.type));
-                if (instr.constant.notify != 0)
+                if (obj && instr.constant.notify != 0)
                     enginePrivate->capturedProperties <<
                         QmlEnginePrivate::CapturedProperty(obj, instr.constant.idx, instr.constant.notify); 
                 state = Reset;
diff --git a/src/declarative/qml/qmlcontext.cpp b/src/declarative/qml/qmlcontext.cpp
index b605869..440f4b8 100644
--- a/src/declarative/qml/qmlcontext.cpp
+++ b/src/declarative/qml/qmlcontext.cpp
@@ -86,8 +86,15 @@ void QmlContextPrivate::destroyed(QObject *obj)
         }
     }
 
-    for (int ii = 0; ii < notifies.count(); ++ii) {
-        QMetaObject::activate(q, notifies[ii] + notifyIndex, 0);
+    // There is no need to emit these notifications if our parent is in the 
+    // process of being deleted (which is *probably* why obj has been destroyed
+    // anyway), as we're about to get deleted which will invalidate all the
+    // expressions that could depend on us
+    QObject *parent = q->parent();
+    if (!parent || !QObjectPrivate::get(parent)->wasDeleted) {
+        for (int ii = 0; ii < notifies.count(); ++ii) {
+            QMetaObject::activate(q, notifies[ii] + notifyIndex, 0);
+        }
     }
 }