[Bug c++/78249] In consistent results for 0.0 * inf when optimizer is enabled

[rguenth at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=78249

--- Comment #3 from Richard Biener <rguenth at gcc dot gnu.org> ---
libstdc++ uses __builtin_huge_val().  On trunk I see some changes but CCP still
folds __builtin_huge_val () * 0.0 to -NaN.