Index: src/libcfa/concurrency/alarm.h
===================================================================
--- src/libcfa/concurrency/alarm.h	(revision c81ebf924fb91ca84affb100df945a8a6441e956)
+++ src/libcfa/concurrency/alarm.h	(revision e60e0dc41c51d3729b99dd9bd3c6864794d982ce)
@@ -19,8 +19,9 @@
 
 #include <stdbool.h>
+#include <stdint.h>
 
 #include "assert"
 
-typedef unsigned long int __cfa_time_t;
+typedef uint64_t __cfa_time_t;
 
 struct thread_desc;
