https://gcc.gnu.org/bugzilla/show_bug.cgi?id=79677
--- Comment #6 from Jakub Jelinek <jakub at gcc dot gnu.org> --- (In reply to Orion Poplawski from comment #5) > With gcc 7.0.1-0.10.fc26 I'm starting to see errors like: > > cc1plus: error: -Wformat-security ignored without -Wformat > [-Werror=format-security] > > If this is intended, we're going to need to fix redhat-rpm-config to change: > > %__global_compiler_flags -O2 -g -pipe -Wall -Werror=format-security > -Wp,-D_FORTIFY_SOURCE=2 -fexceptions -fstack-protector-strong > --param=ssp-buffer-size=4 -grecord-gcc-switches %{_hardened_cflags} > > to add -Wformat. Well, -Wformat is implied by -Wall, so it must be packages doing -Wno-format or similar. -Wformat -Wformat-security -Wno-format used to warn in the past, -Wformat -Werror=format-security -Wno-format used to be quite due to a bug, but now errors out. We have one instance of this problem in gcc too: AS_IF([test $enable_build_format_warnings = no], [wf_opt=-Wno-format],[wf_opt=]) Guess we want there: AS_IF([test $enable_build_format_warnings = no], [wf_opt="-Wno-format -Wno-format-security -Wno-format-y2k -Wno-format-extra-args -Wno-format-zero-length -Wno-format-nonliteral"],[wf_opt=])