title: Custom log level in google logging
body: <p>Is it possible to add custom log level to glog? I couldn't find any examples in their documentation.</p>
  
  <p>Tried to edit glog/logging.h but program is crashing with following bt.</p>
  
  <p><code>#0  0x00007f6aacaca1e6 in google::LogMessage::Init(char const*, int, int, void (google::LogMessage::*)()) ()  from /usr/lib/x86_64-linux-gnu/libglog.so.0</code></p>
  
  <p><code>#1  0x00007f6aacac9b13 in google::LogMessage::LogMessage(char const*, int, int) () from /usr/lib/x86_64-linux-gnu/libglog.so.0</code></p>