[Bug libstdc++/82496] Optimization breaks duration_cast

[jeff.benshetler at stackpath dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=82496

--- Comment #4 from Jeff Benshetler <jeff.benshetler at stackpath dot com> ---
My apologies. Adding -Wall shows:
warning: no return statement in function returning non-void [-Wreturn-type]