diff --git a/src/runtime/debug/debug.go b/src/runtime/debug/debug.go
index 8c805b89a0..38e6ab763b 100644
--- a/src/runtime/debug/debug.go
+++ b/src/runtime/debug/debug.go
@@ -1,4 +1,8 @@
-// Package debug is a dummy package that is not yet implemented.
+// Portions copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Package debug is a very partially implemented package to allow compilation.
 package debug
 
 import (