This was confusing when I was trying to fix go build -o.
Perhaps due to that fix, this can now be simplified from
three functions to one.

Change-Id: I878a6d243b14132a631e7c62a3bb6d101bc243ea
Reviewed-on: https://go-review.googlesource.com/13027Reviewed-by: Ian Lance Taylor <iant@golang.org>