Index: src/cmd/internal/obj/x86/aenum.go
--- src/cmd/internal/obj/x86/aenum.go.orig
+++ src/cmd/internal/obj/x86/aenum.go
@@ -201,6 +201,7 @@ const (
 	ADECL
 	ADECQ
 	ADECW
+	ADEFERRET
 	ADIVB
 	ADIVL
 	ADIVPD
