The functions warnc, errc in bsd/err.h should have printf format string annotations, so that GCC can warn about their misuse. setproctitle in bsd/unistd.h should should have a format string, too. It seems the __printflike macro already provides a means to achieve this.
This bug appears to have been reported against 'rawhide' during the Fedora 22 development cycle. Changing version to '22'. More information and reason for this action is here: https://fedoraproject.org/wiki/Fedora_Program_Management/HouseKeeping/Fedora22
It would be best if this was addressed by upstream. I'll inquire about it. Aside from that, patches are welcome.
Fedora 22 changed to end-of-life (EOL) status on 2016-07-19. Fedora 22 is no longer maintained, which means that it will not receive any further security or bug fix updates. As a result we are closing this bug. If you can reproduce this bug against a currently maintained version of Fedora please feel free to reopen this bug against that version. If you are unable to reopen this bug, please file a new report against the current release. If you experience problems, please add a comment to this bug. Thank you for reporting this bug and we are sorry it could not be fixed.