fix build on linux
fix build on linux

kaustavha/luvit,luvit/luvit,boundary/luvit,boundary/luvit,connectFree/lev,zhaozg/luvit,bsn069/luvit,luvit/luvit,GabrielNicolasAvellaneda/luvit-upstream,AndrewTsao/luvit,sousoux/luvit,zhaozg/luvit,GabrielNicolasAvellaneda/luvit-upstream,connectFree/lev,rjeli/luvit,DBarney/luvit,sousoux/luvit,bsn069/luvit,DBarney/luvit,kaustavha/luvit,sousoux/luvit,boundary/luvit,boundary/luvit,kaustavha/luvit,sousoux/luvit,AndrewTsao/luvit,GabrielNicolasAvellaneda/luvit-upstream,DBarney/luvit,rjeli/luvit,sousoux/luvit,boundary/luvit,bsn069/luvit,rjeli/luvit,rjeli/luvit,sousoux/luvit,DBarney/luvit,boundary/luvit,GabrielNicolasAvellaneda/luvit-upstream,AndrewTsao/luvit