diff --git a/src/pkg/runtime/debug/stack.go b/src/pkg/runtime/debug/stack.go
index a533a5c3bf4..2896b21417a 100644
--- a/src/pkg/runtime/debug/stack.go
+++ b/src/pkg/runtime/debug/stack.go
@@ -29,6 +29,8 @@ func PrintStack() {
 // For each routine, it includes the source line information and PC value,
 // then attempts to discover, for Go functions, the calling function or
 // method and the text of the line containing the invocation.
+//
+// This function is deprecated. Use package runtime's Stack instead.
 func Stack() []byte {
 	return stack()
 }