No changes in the actual generated compiler code.

Change-Id: Ibae71b6de35722792cc94fea0cdfa5e53cf3c83e
Reviewed-on: https://go-review.googlesource.com/108476
Run-TryBot: Alberto Donizetti <alb.donizetti@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>