[tz] Irish Standard Time vs Irish Summer Time
tgl at sss.pgh.pa.us
Fri Jan 19 00:39:50 UTC 2018
Zefram <zefram at fysh.org> writes:
> There was indeed a significant chance of the negative SAVE value breaking
> alternate zic implementations, and now that that's turned out to be
> the case that's good cause to postpone this correction, or at least the
> expressing of it in this natural manner. The tzdb does have unusually
> high stability requirements. But that's not a reason to keep the database
> forever inaccurate.
I'm not sure that it's "inaccurate". The question is more about what is
the meaning of tm_isdst = 1. It's clear from this discussion that an
awful lot of code believes it means "local time is advanced now compared
to what it is when tm_isdst = 0". Arguing that it should reflect a
legalistic definition of DST, rather than an operational definition,
is just an argument; it's not conclusive.
FWIW, I share the opinion that this change was misguided.
regards, tom lane
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