https://gcc.gnu.org/bugzilla/show_bug.cgi?id=79879
--- Comment #10 from Andrew Pinski <pinskia at gcc dot gnu.org> --- (In reply to Lukas Wyporek from comment #9) > No, my mistake. -Wall shows warnings only if format parameter is LITERAL. > When format parameter is pointer to string (buffer) - there are no warnings. Try -Wformat-security . This is not enabled by default.