diff --git a/src/LinearMath/btQuaternion.h b/src/LinearMath/btQuaternion.h
index 7f7a813c4..aec25a549 100644
--- a/src/LinearMath/btQuaternion.h
+++ b/src/LinearMath/btQuaternion.h
@@ -210,7 +210,7 @@ public:
 		}
 	}
 
-	
+	SIMD_FORCE_INLINE const btScalar& getW() const { return m_unusedW; }
 
 };
 
diff --git a/src/btBulletDynamicsCommon.h b/src/btBulletDynamicsCommon.h
index 8d5cb6ed0..2fe951ddf 100644
--- a/src/btBulletDynamicsCommon.h
+++ b/src/btBulletDynamicsCommon.h
@@ -22,10 +22,13 @@ subject to the following restrictions:
 #include "BulletDynamics/Dynamics/btDiscreteDynamicsWorld.h"
 #include "BulletDynamics/Dynamics/btSimpleDynamicsWorld.h"
 #include "BulletDynamics/Dynamics/btRigidBody.h"
+#include "BulletDynamics/Dynamics/btMassProps.h"
+
 #include "BulletDynamics/ConstraintSolver/btPoint2PointConstraint.h"
 #include "BulletDynamics/ConstraintSolver/btHingeConstraint.h"
 #include "BulletDynamics/ConstraintSolver/btGeneric6DofConstraint.h"
 
+
 #include "BulletDynamics/ConstraintSolver/btSequentialImpulseConstraintSolver.h"
 ///Vehicle simulation, with wheel contact simulated by raycasts
 #include "BulletDynamics/Vehicle/btRaycastVehicle.h"