Do not call InternalClass::changeVTable directly

vtable changes need to happen when the internal class
is being constructed, not later on.

Change-Id: Ibb9515745c9fc3507a5a90b4cc50a33e2e0d3f99
Reviewed-by: Simon Hausmann <simon.hausmann@digia.com>

2 files changed, 6 insertions, 4 deletions

diff --git a/src/qml/jsruntime/qv4engine.cpp b/src/qml/jsruntime/qv4engine.cpp
index 539bc5ddd6..f55b47c7e0 100644
--- a/src/qml/jsruntime/qv4engine.cpp
+++ b/src/qml/jsruntime/qv4engine.cpp
@@ -195,9 +195,9 @@ ExecutionEngine::ExecutionEngine(QQmlJS::EvalISelFactory *factory)
     identifierTable = new IdentifierTable(this);
 
     emptyClass =  new (classPool.allocate(sizeof(InternalClass))) InternalClass(this);
-    executionContextClass = emptyClass->changeVTable(&ExecutionContext::static_vtbl);
-    stringClass = emptyClass->changeVTable(&String::static_vtbl);
-    regExpValueClass = emptyClass->changeVTable(&RegExp::static_vtbl);
+    executionContextClass = InternalClass::create(this, &ExecutionContext::static_vtbl, 0);
+    stringClass = InternalClass::create(this, &String::static_vtbl, 0);
+    regExpValueClass = InternalClass::create(this, &RegExp::static_vtbl, 0);
 
     id_undefined = newIdentifier(QStringLiteral("undefined"));
     id_null = newIdentifier(QStringLiteral("null"));
@@ -230,7 +230,7 @@ ExecutionEngine::ExecutionEngine(QQmlJS::EvalISelFactory *factory)
     id_toString = newIdentifier(QStringLiteral("toString"));
     id_valueOf = newIdentifier(QStringLiteral("valueOf"));
 
-    ObjectPrototype *objectPrototype = new (memoryManager) ObjectPrototype(emptyClass->changeVTable(&ObjectPrototype::static_vtbl));
+    ObjectPrototype *objectPrototype = new (memoryManager) ObjectPrototype(InternalClass::create(this, &ObjectPrototype::static_vtbl, 0));
     objectClass = InternalClass::create(this, &Object::static_vtbl, objectPrototype);
     Q_ASSERT(objectClass->vtable == &Object::static_vtbl);
 
diff --git a/src/qml/jsruntime/qv4internalclass.cpp b/src/qml/jsruntime/qv4internalclass.cpp
index 29ede3d104..761a180722 100644
--- a/src/qml/jsruntime/qv4internalclass.cpp
+++ b/src/qml/jsruntime/qv4internalclass.cpp
@@ -183,6 +183,8 @@ InternalClass *InternalClass::changeMember(String *string, PropertyAttributes da
 InternalClass *InternalClass::create(ExecutionEngine *engine, const ManagedVTable *vtable, Object *proto)
 {
     InternalClass *c = engine->emptyClass->changeVTable(vtable);
+    if (!proto)
+        return c;
     return c->changePrototype(proto);
 }