gmtime is not POSIX compliant due to leap seconds

Warner Losh imp at
Sun May 20 18:14:33 UTC 2018

On Sun, May 20, 2018 at 11:18 AM, Garrett Wollman <wollman at>

> On May 20, 2018 1:08:13 PM EDT, Eitan Adler <lists at> wrote:
> > This means that gmtime ought not to be affected by leap seconds.
> If you are getting leap-second adjustments, then you are using a
> nonstandard build of the data files with that feature enabled. Don't do
> that if POSIX behavior is what you want.

If you have those options enabled, the times are TAI times, not UTC times,
so the conversions are correct...

Furthermore, leap seconds must die.


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