Fix pointer-offset iterator

Author: smowton

src/util/pointer_offset_size.cpp

@@ -21,8 +21,8 @@ Author: Daniel Kroening, [email protected]
 
 #include "pointer_offset_size.h"
 
-member_offset_iterator::member_offset_iterator(const struct_typet _type,
-                                               const namespacet _ns) :
+member_offset_iterator::member_offset_iterator(const struct_typet& _type,
+                                               const namespacet& _ns) :
   type(_type),
   ns(_ns),
   bit_field_bits(0),

src/util/pointer_offset_size.h

@@ -28,8 +28,8 @@ class member_offset_iterator {
   const namespacet &ns;
   size_t bit_field_bits;
  public:
-  member_offset_iterator(const struct_typet _type,
-                         const namespacet _ns);
+  member_offset_iterator(const struct_typet& _type,
+                         const namespacet& _ns);
   member_offset_iterator& operator++();
   const refst& operator*() const { return current; }
   const refst* operator->() const { return &current; }