[Bug c/89072] -Wall -Werror should be defaults

[segher at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=89072

--- Comment #7 from Segher Boessenkool <segher at gcc dot gnu.org> ---
-Werror always is wrong, for any sane users.  Always.  Not just "in general".