Index: src/libcfa/concurrency/alarm.h
===================================================================
--- src/libcfa/concurrency/alarm.h	(revision c81ebf924fb91ca84affb100df945a8a6441e956)
+++ src/libcfa/concurrency/alarm.h	(revision 5bd0aad2eb20d7e1f1b3a2f5e19678c448dd7e13)
@@ -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;