diff --git a/src/cmd/compile/internal/gc/gen.go b/src/cmd/compile/internal/gc/gen.go
index 764895f..6390818 100644
--- a/src/cmd/compile/internal/gc/gen.go
+++ b/src/cmd/compile/internal/gc/gen.go
@@ -141,6 +141,8 @@
 	return lab
 }
 
+// There is a copy of checkgoto in the new SSA backend.
+// Please keep them in sync.
 func checkgoto(from *Node, to *Node) {
 	if from.Sym == to.Sym {
 		return