Make sure we destroy all QV4::QObjectWrapper objects

Delay freeing QObjectWrapper Value to MemoryManager::sweep() to make sure
we can destroy all QObjectWrapper objects.
We also keep track of QObjectWrapper in QV4::Heap::ModelObject to make
sure we destory them in QV4::MemoryManager::sweep()

Change-Id: I3a8a3b07faab1f88c2eb746f68aa8d9584b40026
Reviewed-by: Simon Hausmann <simon.hausmann@theqtcompany.com>

1 files changed, 20 insertions, 1 deletions

diff --git a/src/qml/jsruntime/qv4persistent.cpp b/src/qml/jsruntime/qv4persistent.cpp
index 4a0f84b685..1b0d6383e0 100644
--- a/src/qml/jsruntime/qv4persistent.cpp
+++ b/src/qml/jsruntime/qv4persistent.cpp
@@ -34,6 +34,7 @@
 #include "qv4persistent_p.h"
 #include <private/qv4mm_p.h>
 #include "qv4object_p.h"
+#include "qv4qobjectwrapper_p.h"
 #include "PageAllocation.h"
 
 using namespace QV4;
@@ -381,7 +382,7 @@ WeakValue &WeakValue::operator=(const WeakValue &other)
 
 WeakValue::~WeakValue()
 {
-    PersistentValueStorage::free(val);
+    free();
 }
 
 void WeakValue::set(ExecutionEngine *engine, const Value &value)
@@ -412,3 +413,21 @@ void WeakValue::markOnce(ExecutionEngine *e)
     val->mark(e);
 }
 
+void WeakValue::free()
+{
+    if (!val)
+        return;
+
+    ExecutionEngine *e = engine();
+    if (e && val->as<QObjectWrapper>()) {
+        // Some QV4::QObjectWrapper Value will be freed in WeakValue::~WeakValue() before MemoryManager::sweep() is being called,
+        // in this case we will never have a chance to call detroyObject() on those QV4::QObjectWrapper objects.
+        // Here we don't free these Value immediately, instead we keep track of them to free them later in MemoryManager::sweep()
+        e->memoryManager->m_pendingFreedObjectWrapperValue.push_back(val);
+    } else {
+        PersistentValueStorage::free(val);
+    }
+
+    val = 0;
+}
+