Summary:
Fixing following the issues raised by nsuke on github
following his diff (https://github.com/facebook/folly/pull/112)

Test Plan: visual inspection, tested build on arch linux

Reviewed By: davejwatson@fb.com

Subscribers: folly-diffs@

FB internal diff: D1807378

Tasks: 5909189

Signature: t1:1807378:1422403093:ca024f396a27ecd9b304c57643f0107764a38ca1