RE: Calendar - leap seconds

[Wilhelm.Spickermann@t-online.de (Wilhelm Spickermann)]

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On 17-Mar-01 singlespeeder wrote:
> How do I handle leap seconds using Ada.Calendar as the subtype
> Day_Duration
> doesn't have enough space for them?
> 
> ARM 9.6(11):
> subtype Day_Duration is Duration range 0.0 ..  86_400.0;
> 
> 
> Am I best just declaring my own subtype with the required range?

But, will it help? Does Your operating system still support leap
seconds? AFAIK the BIG problem is, that most operating
systems no longer support leap seconds, as POSIX has switched to
ignoring them (<a time_t value of 536457599 shall correspond to "Wed Dec
31 23:59:59 UTC 1986">). I don�t have the IEEE 1003.1 standard, but
I�ve heard, that they even gave an arithmetic expression for computing
a time_t value from a broken time (without using a leap second list).
Do our library implementations depend on this? My first impression for
GNAT is that they do. So I cannot switch my Operating System (Linux)
from using /usr/share/zoneinfo/posix/Europe/Berlin (no leap seconds)
to /usr/share/zoneinfo/right/Europe/Berlin (with leap seconds) without
breaking Ada. :-(

Wilhelm