Fix build without glibc
Fix build without glibc

Summary: The preprocessor does not follow normal rules of && evaluation, tries to evaluate __GLIBC_PREREQ(2, 12) even though the defined() check fails.  This breaks the build if __GLIBC_PREREQ is absent.

Test Plan: Try adding #undef __GLIBC_PREREQ above the offending line, build no longer breaks

Reviewed By: igor

Blame Rev: 4c81383628db46d35b674000a3668b5a9a2498a6

hobinyoon/rocksdb,SunguckLee/RocksDB,wlqGit/rocksdb,tsheasha/rocksdb,caijieming-baidu/rocksdb,Vaisman/rocksdb,facebook/rocksdb,NickCis/rocksdb,caijieming-baidu/rocksdb,makelivedotnet/rocksdb,jalexanderqed/rocksdb,RyanTech/rocksdb,wlqGit/rocksdb,JackLian/rocksdb,OverlordQ/rocksdb,zhangpng/rocksdb,zhangpng/rocksdb,tschottdorf/rocksdb,tizzybec/rocksdb,skunkwerks/rocksdb,vmx/rocksdb,biddyweb/rocksdb,SunguckLee/RocksDB,jalexanderqed/rocksdb,OverlordQ/rocksdb,hobinyoon/rocksdb,Applied-Duality/rocksdb,tsheasha/rocksdb,bbiao/rocksdb,wenduo/rocksdb,tizzybec/rocksdb,virtdb/rocksdb,biddyweb/rocksdb,mbarbon/rocksdb,flabby/rocksdb,fengshao0907/rocksdb,SunguckLee/RocksDB,geraldoandradee/rocksdb,wat-ze-hex/rocksdb,SunguckLee/RocksDB,JackLian/rocksdb,facebook/rocksdb,virtdb/rocksdb,siddhartharay007/rocksdb,dkorolev/rocksdb,amyvmiwei/rocksdb,JackLian/rocksdb,skunkwerks/rocksdb,anagav/rocksdb,RyanTech/rocksdb,JohnPJenkins/rocksdb,IMCG/RcoksDB,Applied-Duality/rocksdb,caijieming-baidu/rocksdb,IMCG/RcoksDB,anagav/rocksdb,Applied-Duality/rocksdb,Andymic/rocksdb,flabby/rocksdb,alihalabyah/rocksdb,ryneli/rocksdb,Andymic/rocksdb,mbarbon/rocksdb,kaschaeffer/rocksdb,norton/rocksdb,zhangpng/rocksdb,vashstorm/rocksdb,siddhartharay007/rocksdb,luckywhu/rocksdb,wlqGit/rocksdb,Andymic/rocksdb,tsheasha/rocksdb,temicai/rocksdb,wat-ze-hex/rocksdb,Applied-Duality/rocksdb,biddyweb/rocksdb,Andymic/rocksdb,hobinyoon/rocksdb,JohnPJenkins/rocksdb,flabby/rocksdb,jalexanderqed/rocksdb,ylong/rocksdb,alihalabyah/rocksdb,luckywhu/rocksdb,amyvmiwei/rocksdb,facebook/rocksdb,caijieming-baidu/rocksdb,facebook/rocksdb,flabby/rocksdb,tsheasha/rocksdb,virtdb/rocksdb,IMCG/RcoksDB,facebook/rocksdb,vmx/rocksdb,biddyweb/rocksdb,norton/rocksdb,rDSN-Projects/rocksdb.replicated,vmx/rocksdb,bbiao/rocksdb,wat-ze-hex/rocksdb,RyanTech/rocksdb,vashstorm/rocksdb,rDSN-Projects/rocksdb.replicated,msb-at-yahoo/rocksdb,Andymic/rocksdb,RyanTech/rocksdb,amyvmiwei/rocksdb,JackLian/rocksdb,wlqGit/rocksdb,facebook/rocksdb,hobinyoon/rocksdb,msb-at-yahoo/rocksdb,wskplho/rocksdb,facebook/rocksdb,facebook/rocksdb,wat-ze-hex/rocksdb,IMCG/RcoksDB,kaschaeffer/rocksdb,siddhartharay007/rocksdb,SunguckLee/RocksDB,bbiao/rocksdb,rDSN-Projects/rocksdb.replicated,temicai/rocksdb,NickCis/rocksdb,kaschaeffer/rocksdb,RyanTech/rocksdb,RyanTech/rocksdb,wenduo/rocksdb,tsheasha/rocksdb,vashstorm/rocksdb,Andymic/rocksdb,caijieming-baidu/rocksdb,dkorolev/rocksdb,wenduo/rocksdb,tsheasha/rocksdb,wlqGit/rocksdb,OverlordQ/rocksdb,JackLian/rocksdb,tschottdorf/rocksdb,Andymic/rocksdb,alihalabyah/rocksdb,siddhartharay007/rocksdb,caijieming-baidu/rocksdb,amyvmiwei/rocksdb,tschottdorf/rocksdb,mbarbon/rocksdb,kaschaeffer/rocksdb,sorphi/rocksdb,sorphi/rocksdb,geraldoandradee/rocksdb,luckywhu/rocksdb,anagav/rocksdb,geraldoandradee/rocksdb,JoeWoo/rocksdb,wat-ze-hex/rocksdb,hobinyoon/rocksdb,wskplho/rocksdb,rDSN-Projects/rocksdb.replicated,vmx/rocksdb,amyvmiwei/rocksdb,msb-at-yahoo/rocksdb,kaschaeffer/rocksdb,skunkwerks/rocksdb,dkorolev/rocksdb,JoeWoo/rocksdb,kaschaeffer/rocksdb,amyvmiwei/rocksdb,IMCG/RcoksDB,JohnPJenkins/rocksdb,bbiao/rocksdb,wenduo/rocksdb,norton/rocksdb,Vaisman/rocksdb,anagav/rocksdb,norton/rocksdb,wat-ze-hex/rocksdb,RyanTech/rocksdb,sorphi/rocksdb,tschottdorf/rocksdb,tschottdorf/rocksdb,makelivedotnet/rocksdb,jalexanderqed/rocksdb,virtdb/rocksdb,wskplho/rocksdb,wskplho/rocksdb,fengshao0907/rocksdb,JoeWoo/rocksdb,makelivedotnet/rocksdb,lgscofield/rocksdb,JohnPJenkins/rocksdb,tsheasha/rocksdb,jalexanderqed/rocksdb,luckywhu/rocksdb,lgscofield/rocksdb,makelivedotnet/rocksdb,tizzybec/rocksdb,mbarbon/rocksdb,OverlordQ/rocksdb,rDSN-Projects/rocksdb.replicated,lgscofield/rocksdb,wat-ze-hex/rocksdb,siddhartharay007/rocksdb,msb-at-yahoo/rocksdb,luckywhu/rocksdb,zhangpng/rocksdb,geraldoandradee/rocksdb,geraldoandradee/rocksdb,temicai/rocksdb,kaschaeffer/rocksdb,wlqGit/rocksdb,makelivedotnet/rocksdb,wat-ze-hex/rocksdb,norton/rocksdb,wskplho/rocksdb,ylong/rocksdb,vmx/rocksdb,alihalabyah/rocksdb,alihalabyah/rocksdb,mbarbon/rocksdb,sorphi/rocksdb,flabby/rocksdb,dkorolev/rocksdb,IMCG/RcoksDB,lgscofield/rocksdb,hobinyoon/rocksdb,caijieming-baidu/rocksdb,anagav/rocksdb,JoeWoo/rocksdb,wenduo/rocksdb,fengshao0907/rocksdb,tizzybec/rocksdb,luckywhu/rocksdb,skunkwerks/rocksdb,Applied-Duality/rocksdb,mbarbon/rocksdb,temicai/rocksdb,luckywhu/rocksdb,vashstorm/rocksdb,tschottdorf/rocksdb,biddyweb/rocksdb,OverlordQ/rocksdb,IMCG/RcoksDB,virtdb/rocksdb,SunguckLee/RocksDB,skunkwerks/rocksdb,vmx/rocksdb,zhangpng/rocksdb,wlqGit/rocksdb,msb-at-yahoo/rocksdb,wenduo/rocksdb,vmx/rocksdb,wskplho/rocksdb,flabby/rocksdb,alihalabyah/rocksdb,JohnPJenkins/rocksdb,OverlordQ/rocksdb,lgscofield/rocksdb,fengshao0907/rocksdb,Vaisman/rocksdb,NickCis/rocksdb,temicai/rocksdb,vashstorm/rocksdb,hobinyoon/rocksdb,bbiao/rocksdb,bbiao/rocksdb,norton/rocksdb,ryneli/rocksdb,anagav/rocksdb,vashstorm/rocksdb,rDSN-Projects/rocksdb.replicated,ryneli/rocksdb,NickCis/rocksdb,ylong/rocksdb,ryneli/rocksdb,mbarbon/rocksdb,vmx/rocksdb,SunguckLee/RocksDB,JoeWoo/rocksdb,ylong/rocksdb,NickCis/rocksdb,NickCis/rocksdb,dkorolev/rocksdb,biddyweb/rocksdb,makelivedotnet/rocksdb,sorphi/rocksdb,JackLian/rocksdb,virtdb/rocksdb,fengshao0907/rocksdb,Vaisman/rocksdb,siddhartharay007/rocksdb,dkorolev/rocksdb,vashstorm/rocksdb,flabby/rocksdb,skunkwerks/rocksdb,bbiao/rocksdb,jalexanderqed/rocksdb,fengshao0907/rocksdb,dkorolev/rocksdb,tizzybec/rocksdb,temicai/rocksdb,ylong/rocksdb,Applied-Duality/rocksdb,ryneli/rocksdb,anagav/rocksdb,OverlordQ/rocksdb,SunguckLee/RocksDB,JohnPJenkins/rocksdb,tsheasha/rocksdb,ylong/rocksdb,Applied-Duality/rocksdb,Vaisman/rocksdb,hobinyoon/rocksdb,makelivedotnet/rocksdb,skunkwerks/rocksdb,wenduo/rocksdb,JoeWoo/rocksdb,geraldoandradee/rocksdb,JoeWoo/rocksdb,zhangpng/rocksdb,lgscofield/rocksdb,norton/rocksdb,ylong/rocksdb,JackLian/rocksdb,zhangpng/rocksdb,tizzybec/rocksdb,amyvmiwei/rocksdb,siddhartharay007/rocksdb,rDSN-Projects/rocksdb.replicated,Vaisman/rocksdb,biddyweb/rocksdb,jalexanderqed/rocksdb,sorphi/rocksdb,lgscofield/rocksdb,norton/rocksdb,ryneli/rocksdb,Andymic/rocksdb,fengshao0907/rocksdb,bbiao/rocksdb,geraldoandradee/rocksdb,Vaisman/rocksdb,wenduo/rocksdb,NickCis/rocksdb,temicai/rocksdb,wskplho/rocksdb,virtdb/rocksdb,JohnPJenkins/rocksdb,msb-at-yahoo/rocksdb,alihalabyah/rocksdb,ryneli/rocksdb,sorphi/rocksdb,tizzybec/rocksdb