adjustments for GCC on Linux

git-svn-id: http://svn.boost.org/svn/boost/trunk@86716 b8fc166d-592f-0410-95f2-cb63ce0dd405
hashed index performance improvements

git-svn-id: http://svn.boost.org/svn/boost/trunk@86717 b8fc166d-592f-0410-95f2-cb63ce0dd405
typo

git-svn-id: http://svn.boost.org/svn/boost/trunk@86718 b8fc166d-592f-0410-95f2-cb63ce0dd405