Update to box2d 2.4.1

src/libraries/box2d/b2_weld_joint.h

@@ -23,12 +23,13 @@
 #ifndef B2_WELD_JOINT_H
 #define B2_WELD_JOINT_H
 
+#include "b2_api.h"
 #include "b2_joint.h"
 
 /// Weld joint definition. You need to specify local anchor points
 /// where they are attached and the relative body angle. The position
 /// of the anchor points is important for computing the reaction torque.
-struct b2WeldJointDef : public b2JointDef
+struct B2_API b2WeldJointDef : public b2JointDef
 {
 	b2WeldJointDef()
 	{
@@ -54,7 +55,7 @@ struct b2WeldJointDef : public b2JointDef
 
 	/// The bodyB angle minus bodyA angle in the reference state (radians).
 	float referenceAngle;
-	
+
 	/// The rotational stiffness in N*m
 	/// Disable softness with a value of 0
 	float stiffness;
@@ -65,7 +66,7 @@ struct b2WeldJointDef : public b2JointDef
 
 /// A weld joint essentially glues two bodies together. A weld joint may
 /// distort somewhat because the island constraint solver is approximate.
-class b2WeldJoint : public b2Joint
+class B2_API b2WeldJoint : public b2Joint
 {
 public:
 	b2Vec2 GetAnchorA() const override;