diff --git a/libc/include/sys/personality.h b/libc/include/sys/personality.h
index 77725508f..8a023f967 100644
--- a/libc/include/sys/personality.h
+++ b/libc/include/sys/personality.h
@@ -29,6 +29,7 @@
 #ifndef _SYS_PERSONALITY_H_
 #define _SYS_PERSONALITY_H_
 
+#include <sys/cdefs.h>
 #include <linux/personality.h>
 
 __BEGIN_DECLS