[Bug bootstrap/90132] make bootstrap fails with -O3 (gcc9 snapshot 20190414)

[jakub at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=90132

--- Comment #6 from Jakub Jelinek <jakub at gcc dot gnu.org> ---
Even in that case, several times in the past we've just decided to recommend
--disable-werror in those cases instead of adding too ugly workarounds for some
warnings (while for the default we always add workarounds or disable warnings
or whatever is needed to make them build cleanly).
The thing is, with too many different optimization options vs. different
targets etc. the support matrix for warning-free builds gets too large.