Your package rust-owning_ref failed to build from source in current F28. https://koji.fedoraproject.org/koji/taskinfo?taskID=24949987 For details on mass rebuild see https://fedoraproject.org/wiki/Fedora_28_Mass_Rebuild
A build was successfull: rust-owning_ref-0.3.3-2.fc28 [1]. No update was found in bodhi. Closing the bug nonetheless. [1] https://koji.fedoraproject.org/koji/buildinfo?buildID=1014815