diff --git a/include/bl31/ehf.h b/include/bl31/ehf.h
index 1446279..c60b04c 100644
--- a/include/bl31/ehf.h
+++ b/include/bl31/ehf.h
@@ -9,6 +9,7 @@
 
 #ifndef __ASSEMBLY__
 
+#include <cdefs.h>
 #include <stdint.h>
 #include <utils_def.h>