[tz] tzcode-2014c breaks applications that use the binary tz files

gunther Vermeir gunther.vermeir at gmail.com
Fri May 23 22:52:40 UTC 2014


just +1 for using the big bang...
because "time stamps before then are physically suspect anyway." :)

On 05/23/2014 11:10 PM, Paul Eggert wrote:
> On 05/23/2014 01:51 PM, Arthur David Olson wrote:
>> Do we face a similar challenge in the 32-bit realm?
>
> Not for Glib, no.  It uses 64-bit signed integers internally.
>
> If this were a problem in the 32-bit realm, wouldn't we have already
> run into it?  Some of tzdata's transitions are before 1901 and thus
> predate the 32-bit window, so I assume that for many years we've been
> approximating them with a transition at -2**31 -- is my assumption
> incorrect?
>
> One other thought, just for fun.  In the 64-bit realm, we could use
> the timestamp of the Big Bang, as time stamps before then are
> physically suspect anyway.  If we use POSIX time, our current best
> guess is that the Big Bang happened 13.82 billion years ago, which (if
> we use the POSIX origin of 1970) would make it -13,820,000,000 *
> 365.2425 * 86400, or -436117076640000000 -- a 59-bit number.  A
> downside of using -436117076640000000 is that we'd need to update that
> number as we get better estimates of when the Big Bang occurred, but
> maybe we could consider this to be part of the fun.  After all, if
> Unix had been developed on a 64-bit machine and had used the Big Bang
> for the time_t origin, a lot of bugs would have been avoided in the
> first place....




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