diff --git a/cpukit/score/include/rtems/score/cpustdatomic.h b/cpukit/score/include/rtems/score/cpustdatomic.h
index 4023d0cbea..945467ee46 100644
--- a/cpukit/score/include/rtems/score/cpustdatomic.h
+++ b/cpukit/score/include/rtems/score/cpustdatomic.h
@@ -20,6 +20,7 @@
 
 #include <stdatomic.h>
 #include <stdbool.h>
+#include <stdint.h>
 
 #ifdef __cplusplus
 extern "C" {