QML: Make Heap::Object and all subclasses trivial

GCC6 might dead-store-eliminate out our secret write to Base::mmdata,
because it expects all memory content to be "undefined" before
constructor calls. Clang might take the same approach if the constructor
of Heap::Object is removed.

By making these structs trivial, it also makes them memcpy-able.

Change-Id: I055b2ad28311b997fbe059849ebda4d5894eaa9b
Reviewed-by: Simon Hausmann <simon.hausmann@qt.io>

1 files changed, 4 insertions, 3 deletions

diff --git a/src/particles/qquickv4particledata.cpp b/src/particles/qquickv4particledata.cpp
index 99451057ce..bd43d45c38 100644
--- a/src/particles/qquickv4particledata.cpp
+++ b/src/particles/qquickv4particledata.cpp
@@ -273,10 +273,11 @@ QT_BEGIN_NAMESPACE
 struct QV4ParticleData : public QV4::Object
 {
     struct Data : QV4::Object::Data {
-        Data(QQuickParticleData *datum, QQuickParticleSystem* particleSystem)
-            : datum(datum)
-            , particleSystem(particleSystem)
+        void init(QQuickParticleData *datum, QQuickParticleSystem* particleSystem)
         {
+            Object::init();
+            this->datum = datum;
+            this->particleSystem = particleSystem;
         }
         QQuickParticleData* datum;//TODO: Guard needed?
         QQuickParticleSystem* particleSystem;