[Bug driver/115990] Consider deprecating -Ofast

[rguenth at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=115990

--- Comment #12 from Richard Biener <rguenth at gcc dot gnu.org> ---
Well, it was also about "GCC sucks, I need to add 20 options to get to the
level of optimization, using ICC I can just use -fast".  So it's about
convenience, and building on the apparent connotation of "fast" with "slightly
unsafe in some cases" people apparently knew.