os: work around inlining bug (issue 2678)
os: work around inlining bug (issue 2678)

TBR=lvd
CC=golang-dev
http://codereview.appspot.com/5534070
abustany/go,abustany/go,abustany/go,abustany/go,abustany/go,abustany/go,abustany/go