1 files changed, 6 insertions, 6 deletions
diff --git a/src/core/timer.h b/src/core/timer.h
index fed15e9165..4168553e9d 100644
--- a/src/core/timer.h
+++ b/src/core/timer.h
@@ -87,11 +87,11 @@ void timer_free_values(Timer *t);
 
 extern const UnitVTable timer_vtable;
 
-const char *timer_state_to_string(TimerState i);
-TimerState timer_state_from_string(const char *s);
+const char *timer_state_to_string(TimerState i) _const_;
+TimerState timer_state_from_string(const char *s) _pure_;
 
-const char *timer_base_to_string(TimerBase i);
-TimerBase timer_base_from_string(const char *s);
+const char *timer_base_to_string(TimerBase i) _const_;
+TimerBase timer_base_from_string(const char *s) _pure_;
 
-const char* timer_result_to_string(TimerResult i);
-TimerResult timer_result_from_string(const char *s);
+const char* timer_result_to_string(TimerResult i) _const_;
+TimerResult timer_result_from_string(const char *s) _pure_;