@@ -47,9 +47,9 @@
  * @brief Initializes an already allocated unlock failed exception.
  *
  * @param lock The lock which could not be unlocked
  * @return An initialized unlock failed exception
  */
-- initWithLock: (nullable id <OFLocking>)lock;
+- initWithLock: (nullable id <OFLocking>)lock OF_DESIGNATED_INITIALIZER;
 @end
 
 OF_ASSUME_NONNULL_END