@@ -43,11 +43,12 @@
  */
 @interface OFTimer: OFObject <OFComparing>
 {
 	OFDate *_fireDate;
 	of_time_interval_t _interval;
-	id _target, _object1, _object2, _object3, _object4;
+	id _target;
+	id _Nullable _object1, _object2, _object3, _object4;
 	SEL _selector;
 	uint8_t _arguments;
 	bool _repeats;
 #ifdef OF_HAVE_BLOCKS
 	of_timer_block_t _block;
@@ -55,11 +56,11 @@
 	bool _valid;
 #ifdef OF_HAVE_THREADS
 	OFCondition *_condition;
 	bool _done;
 #endif
-	OFRunLoop *_inRunLoop;
+	OFRunLoop *_Nullable _inRunLoop;
 }
 
 /*!
  * The time interval in which the timer will repeat, if it is a repeating
  * timer.