diff --git a/vendor/golang.org/x/sys/unix/types_darwin.go b/vendor/golang.org/x/sys/unix/types_darwin.go
index 9fd2aaa..155c2e6 100644
--- a/vendor/golang.org/x/sys/unix/types_darwin.go
+++ b/vendor/golang.org/x/sys/unix/types_darwin.go
@@ -275,3 +275,9 @@
 // uname
 
 type Utsname C.struct_utsname
+
+// Clockinfo
+
+const SizeofClockinfo = C.sizeof_struct_clockinfo
+
+type Clockinfo C.struct_clockinfo