[Bug c/81128] Function multi-versioning does not work with -Ofast

[billy.o.mahony at intel dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=81128

--- Comment #3 from Billy O'Mahony <billy.o.mahony at intel dot com> ---
Created attachment 41585
  --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=41585&action=edit
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