diff --git a/src/syscall/zsysnum_darwin_arm.go b/src/syscall/zsysnum_darwin_arm.go
index 1a53f13..1d76861 100644
--- a/src/syscall/zsysnum_darwin_arm.go
+++ b/src/syscall/zsysnum_darwin_arm.go
@@ -1,6 +1,8 @@
 // mksysnum_darwin.pl /usr/include/sys/syscall.h
 // MACHINE GENERATED BY THE ABOVE COMMAND; DO NOT EDIT
 
+// +build arm,darwin
+
 package syscall
 
 const (