macro for free_struct()

diff --git a/skeletons/constr_SET_OF.c b/skeletons/constr_SET_OF.c
index 7ca23a4..bb6d2d3 100644
--- a/skeletons/constr_SET_OF.c
+++ b/skeletons/constr_SET_OF.c
@@ -798,7 +798,7 @@
 		for(i = 0; i < list->count; i++) {
 			void *memb_ptr = list->array[i];
 			if(memb_ptr)
-			elm->type->free_struct(elm->type, memb_ptr, 0);
+			ASN_STRUCT_FREE(*elm->type, memb_ptr);
 		}
 		list->count = 0;	/* No meaningful elements left */
 
@@ -925,7 +925,7 @@
 				ASN_DEBUG("Failed decoding %s of %s (SET OF)",
 					elm->type->name, td->name);
 			}
-			if(ptr) elm->type->free_struct(elm->type, ptr, 0);
+			if(ptr) ASN_STRUCT_FREE(*elm->type, ptr);
 			_ASN_DECODE_FAILED;
 		}