Since it mentions the Debian hardening wiki, -D_FORTIFY_SOURCE=2 is useful too. I have mixed feelings about -Wall, sometimes it produces useful warnings, other

Since it mentions the Debian hardening wiki, -D_FORTIFY_SOURCE=2 is useful too. I have mixed feelings about -Wall, sometimes it produces useful warnings, other times its just too many false positives. I prefer to turn on all warnings, and then explicitly turn off warnings I don't want to see (-Wno-pointer-sign for example), as new compiler versions may add new warnings that could turn out to be useful.