add note about thread local leakage
add note about thread local leakage

chuz/cglib,TopicusZorg/cglib,lukesandberg/cglib,baishuo/cglib,HubSpot/cglib,mohanaraosv/cglib,lncosie/cglib,mcculls/cglib,ligzy/cglib,evertrue/cglib,292388900/cglib,xgbj/cglib,liuyb02/cglib,wangf111/cglib,mcmakev/cglib,cglib/cglib,yseasony/cglib