Failed at https://storage.googleapis.com/go-build-log/9875de36/nacl-amd64p32_931ba6cf.log

Change-Id: I2bc204ed58da543ee2534b69c29c8e8485d54683
Reviewed-on: https://go-review.googlesource.com/19155
Run-TryBot: Russ Cox <rsc@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Reviewed-by: Austin Clements <austin@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>