diff --git a/include/utils.h b/include/utils.h
index 5cf34ab37..6c5b8e91c 100644
--- a/include/utils.h
+++ b/include/utils.h
@@ -11,6 +11,7 @@
 #define _UTILS_H_
 
 #include <stdlib.h>
+#include <stdint.h>
 #include <sched.h>
 #include <assert.h>
 
@@ -121,7 +122,7 @@ int strftimespec(char *s, size_t max, const char *format, struct timespec *ts)
  * @param set A cpu bitmask
  * @return The opaque cpu_set_t datatype
  */
-cpu_set_t integer_to_cpuset(int set);
+cpu_set_t integer_to_cpuset(uintmax_t set);
 
 #ifdef WITH_JANSSON
   #include <jansson.h>
diff --git a/lib/utils.c b/lib/utils.c
index 918841a75..ac5b0a1f6 100644
--- a/lib/utils.c
+++ b/lib/utils.c
@@ -132,7 +132,7 @@ char * vstrcatf(char **dest, const char *fmt, va_list ap)
 	return *dest;
 }
 
-cpu_set_t integer_to_cpuset(int set)
+cpu_set_t integer_to_cpuset(uintmax_t set)
 {
 	cpu_set_t cset;