[Bug driver/115990] Consider deprecating -Ofast

[rguenth at gcc dot gnu.org]

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

--- Comment #13 from Richard Biener <rguenth at gcc dot gnu.org> ---
Note that -ffast-math isn't in any way better, it doesn't suggest wrong-math
either.  It possibly should have been -fno-ieee-conformant-math or so.

clang for example enables -fno-semantic-interposition by default which breaks
valid programs.  With GCC it's part of -Ofast.