fixes initialization order of variables

cpp/particles/p2p/p2p_ghost_collisions.hpp

@@ -82,7 +82,13 @@ class p2p_ghost_collisions
         std::vector <partsize_t> collision_pairs_global;
 
 public:
-    p2p_ghost_collisions(): current_particle_shape(SPHERE), cylinder_width(1.0), cylinder_length(1.0), disk_width(1.0), isActive(true), synchronisation(false) {}
+    p2p_ghost_collisions():
+        isActive(true),
+        synchronisation(false),
+        cylinder_width(1.0),
+        cylinder_length(1.0),
+        disk_width(1.0),
+        current_particle_shape(SPHERE) {}
 
 
     void copy_from_p2p_ghost_collisions(const p2p_ghost_collisions<real_number, partsize_t>& src)