https://gcc.gnu.org/bugzilla/show_bug.cgi?id=61166
--- Comment #12 from Kan Liu <kan.liu.229 at gmail dot com> ---
(In reply to Jonathan Wakely from comment #11)
> (In reply to Kan Liu from comment #10)
> > _Select_type already does the overflow check, so *template implemented
> > operators* is still redundant I think.
>
> You can't use _Select_type on a literal operator that is not a template.
>
> > Since the standard units (std::hours,
> > milliseconds ...) requires the duration::rep to be *int64_t*,
>
> No it doesn't, only chrono::nanoseconds is required to have a 64-bit
> representation. chrono::hours and chrono::minutes are allowed to have fewer
> than 32 bits ("at least 23 bits" and "at least 29 bits" respectively).
>
> > there's no
> > need to do too much check.
>
> Not all values of uint64_t fit in int64_t
Wow... I see
