diff --git a/doc/go1.5.txt b/doc/go1.5.txt
index 524c584a7b..20ad6b2437 100644
--- a/doc/go1.5.txt
+++ b/doc/go1.5.txt
@@ -56,6 +56,7 @@ net/http: support for setting trailers from a server Handler (https://golang.org
 net/http: ignore the Unix epoch time in ServeContent (https://golang.org/cl/7915)
 net/http/cgi: fix REMOTE_ADDR, REMOTE_HOST, add REMOTE_PORT (https://golang.org/cl/4933)
 net/smtp: add TLSConnectionState accessor (https://golang.org/cl/2151)
+os: add LookupEnv (https://golang.org/cl/9791)
 os/signal: add Ignore and Reset (https://golang.org/cl/3580)
 reflect: add ArrayOf (https://golang.org/cl/4111)
 reflect: add FuncOf (https://golang.org/cl/1996)