In file included from main.cpp:35:0:
buffered_reader.h: In member function 'int32_t BufferedReader::Read(char*, int32_t)':
buffered_reader.h:11:23: error: comparison between signed and unsigned integer expressions [-Werror=sign-compare]
     while (s.length() < buffer_len) {
            ~~~~~~~~~~~^~~~~~~~~~~~
cc1plus: all warnings being treated as errors