fix compilation error on ubuntu
fix compilation error on ubuntu

glglwty/rDSN,qinzuoyan/rDSN,linearregression/rDSN,mkhoeini/rDSN,linearregression/rDSN,qinzuoyan/rDSN,whiker/rDSN,whiker/rDSN,lshmouse/rDSN,pandaworrior/rDSN,imzhenyu/rDSN,lshmouse/rDSN,imzhenyu/rDSN,goksyli/rDSN,imzhenyu/rDSN,linearregression/rDSN,imzhenyu/rDSN,lshmouse/rDSN,shengofsun/rDSN,lshmouse/rDSN,qinzuoyan/rDSN,shengofsun/rDSN,shengofsun/rDSN,shengofsun/rDSN,whiker/rDSN,mcfatealan/rDSN,ykwd/rDSN,lshmouse/rDSN,pandaworrior/rDSN,lshmouse/rDSN,imzhenyu/rDSN,glglwty/rDSN,pandaworrior/rDSN,qinzuoyan/rDSN,goksyli/rDSN,glglwty/rDSN,ykwd/rDSN,Microsoft/rDSN,shengofsun/rDSN,glglwty/rDSN,qinzuoyan/rDSN,shengofsun/rDSN,goksyli/rDSN,whiker/rDSN,imzhenyu/rDSN,ykwd/rDSN,qinzuoyan/rDSN,mcfatealan/rDSN,imzhenyu/rDSN,Microsoft/rDSN,Microsoft/rDSN,mcfatealan/rDSN,Microsoft/rDSN,imzhenyu/rDSN,lshmouse/rDSN,Microsoft/rDSN,shengofsun/rDSN,whiker/rDSN,mkhoeini/rDSN,lshmouse/rDSN,mcfatealan/rDSN,qinzuoyan/rDSN,Microsoft/rDSN,pandaworrior/rDSN,Microsoft/rDSN,ykwd/rDSN,qinzuoyan/rDSN,pandaworrior/rDSN,goksyli/rDSN,Microsoft/rDSN,mkhoeini/rDSN,ykwd/rDSN,mkhoeini/rDSN,shengofsun/rDSN,linearregression/rDSN,glglwty/rDSN