Added -Werror back.
Added -Werror back.

eric-haibin-lin/peloton,eric-haibin-lin/peloton,eric-haibin-lin/peloton,eric-haibin-lin/peloton,eric-haibin-lin/peloton,eric-haibin-lin/peloton,eric-haibin-lin/peloton