diff --git a/doc/go1.6.txt b/doc/go1.6.txt
index 3027f5a983..83242e16bf 100644
--- a/doc/go1.6.txt
+++ b/doc/go1.6.txt
@@ -20,6 +20,7 @@ image: add NYCbCrA types (https://golang.org/cl/15671)
 math/rand: add Read (https://golang.org/cl/14522)
 net/http: HTTP/2.0 support (many CLs)
 net/url: make *url.Error implement net.Error (https://golang.org/cl/15672)
+runtime: only one goroutine in traceback (https://golang.org/cl/16512) maybe
 strconv: QuoteToGraphic (https://golang.org/cl/14184/)
 text/template: ExecError (https://golang.org/cl/13957/)
 text/template: trimming spaces (https://golang.org/cl/14391/)