Fix compilation on Mac OS X 10.8 and eariler
Fix compilation on Mac OS X 10.8 and eariler

jhuapl-saralab/re2,skunkwerks/re2,jhuapl-saralab/re2,skunkwerks/re2,skunkwerks/re2,jhuapl-saralab/re2,janestreet/re2,jhuapl-saralab/re2,skunkwerks/re2,skunkwerks/re2,skunkwerks/re2,janestreet/re2,jhuapl-saralab/re2,janestreet/re2,janestreet/re2,jhuapl-saralab/re2,janestreet/re2,janestreet/re2