fix build on 32-bit.
fix build on 32-bit.

jerk1991/muduo,lizj3624/muduo,KunYi/muduo,shenhzou654321/muduo,ucfree/muduo,floristt/muduo,zouzl/muduo-learning,lvmaoxv/muduo,lizj3624/http-github.com-chenshuo-muduo-,jxd134/muduo,xzmagic/muduo,yunhappy/muduo,pthreadself/muduo,devsoulwolf/muduo,lizj3624/http-github.com-chenshuo-muduo-,june505/muduo,SourceInsight/muduo,lizhanhui/muduo,zxylvlp/muduo,SuperMXC/muduo,shuang-shuang/muduo,DongweiLee/muduo,mitliucak/muduo,lizj3624/http-github.com-chenshuo-muduo-,Cofyc/muduo,zxylvlp/muduo,wangweihao/muduo,zouzl/muduo-learning,decimalbell/muduo,mitliucak/muduo,nestle1998/muduo,lizj3624/http-github.com-chenshuo-muduo-,lizj3624/http-github.com-chenshuo-muduo-,Cofyc/muduo,dhanzhang/muduo,westfly/muduo,dhanzhang/muduo,Cofyc/muduo,kidzyoung/muduo,KingLebron/muduo,devsoulwolf/muduo,jerk1991/muduo,danny200309/muduo,huan80s/muduo,SourceInsight/muduo,daodaoliang/muduo,SourceInsight/muduo,huan80s/muduo,danny200309/muduo,shenhzou654321/muduo,devsoulwolf/muduo,xzmagic/muduo,zouzl/muduo-learning,mitliucak/muduo,devsoulwolf/muduo,zhanMingming/muduo,wangweihao/muduo,guker/muduo,KublaikhanGeek/muduo,KingLebron/muduo,youprofit/muduo,tsh185/muduo,floristt/muduo,wangweihao/muduo,lizhanhui/muduo,tsh185/muduo,SuperMXC/muduo,ucfree/muduo,lvshiling/muduo,june505/muduo,lvmaoxv/muduo,lizj3624/muduo,KingLebron/muduo,lizj3624/muduo,guker/muduo,SourceInsight/muduo,floristt/muduo,SourceInsight/muduo,decimalbell/muduo,decimalbell/muduo,lizj3624/muduo,danny200309/muduo,zhuangshi23/muduo,decimalbell/muduo,lizj3624/muduo,ywy2090/muduo,flyfeifan/muduo,shenhzou654321/muduo,nestle1998/muduo,shenhzou654321/muduo,SuperMXC/muduo,yunhappy/muduo,decimalbell/muduo,ucfree/muduo,SuperMXC/muduo,ywy2090/muduo,ucfree/muduo,fc500110/muduo,huan80s/muduo,jxd134/muduo,floristt/muduo,dhanzhang/muduo,zxylvlp/muduo,wangweihao/muduo,fc500110/muduo,KunYi/muduo,pthreadself/muduo,wangweihao/muduo,shenhzou654321/muduo,dhanzhang/muduo,Cofyc/muduo,huan80s/muduo,SuperMXC/muduo,lvshiling/muduo,westfly/muduo,floristt/muduo,ucfree/muduo,mitliucak/muduo,KublaikhanGeek/muduo,flyfeifan/muduo,penyatree/muduo,danny200309/muduo,huan80s/muduo,mitliucak/muduo,penyatree/muduo,Cofyc/muduo,zhuangshi23/muduo,dhanzhang/muduo,westfly/muduo,danny200309/muduo,kidzyoung/muduo,shuang-shuang/muduo,DongweiLee/muduo,KingLebron/muduo,KingLebron/muduo,zhuangshi23/muduo,zhanMingming/muduo,devsoulwolf/muduo,daodaoliang/muduo,youprofit/muduo