Your package gksu-polkit failed to build from source in current rawhide. http://koji.fedoraproject.org/koji/taskinfo?taskID=6972572 For details on mass rebuild see https://fedoraproject.org/wiki/Fedora_21_Mass_Rebuild
Created attachment 904857 [details] build.log
Created attachment 904858 [details] root.log
Created attachment 904859 [details] state.log