[Bug tree-optimization/104601] [11/12 Regression] Invalid branch elimination at -O2

[pinskia at gcc dot gnu.org via Gcc-bugs]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=104601

--- Comment #5 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
But adding noipa to f does though:
[[gnu::noipa]]
std::optional<int> f() { return 1; }