diff --git a/cmd/stringer/stringer.go b/cmd/stringer/stringer.go
index 5d367757f4..78d7299bae 100644
--- a/cmd/stringer/stringer.go
+++ b/cmd/stringer/stringer.go
@@ -126,7 +126,7 @@ func main() {
 	}
 
 	// Print the header and package clause.
-	g.Printf("// Code generated by \"stringer %s\"; DO NOT EDIT\n", strings.Join(os.Args[1:], " "))
+	g.Printf("// Code generated by \"stringer %s\"; DO NOT EDIT.\n", strings.Join(os.Args[1:], " "))
 	g.Printf("\n")
 	g.Printf("package %s", g.pkg.name)
 	g.Printf("\n")