[tz] Problem with historical Asia/Manila?

[Paul Goyette]

According to the asia file, the Philippines jumped 24 hours on May 11, 
1899, from -15:56:00 to +8:04:00 (they moved the international date 
line?)

# Zone  NAME            GMTOFF  RULES   FORMAT  [UNTIL]
Zone    Asia/Manila     -15:56:00 -     LMT     1844 Dec 31
                         8:04:00 -       LMT     1899 May 11
                         8:00    Phil    +08/+09 1942 May
                         9:00    -       +09     1944 Nov
                         8:00    Phil    +08/+09


Yet zdump shows only a 4-minute step in local time, rather than the 
expected 24-hour step:

# zdump -c 1815,2018 -v Asia/Manila
Asia/Manila  -9223372036854775808 = NULL
Asia/Manila  -9223372036854689408 = NULL
Asia/Manila  Tue Dec 31 15:55:59 1844 UT = Mon Dec 30 23:59:59 1844 LMT isdst=0 gmtoff=-57360
Asia/Manila  Tue Dec 31 15:56:00 1844 UT = Wed Jan  1 00:00:00 1845 LMT isdst=0 gmtoff=29040
Asia/Manila  Wed May 10 15:55:59 1899 UT = Wed May 10 23:59:59 1899 LMT isdst=0 gmtoff=29040
Asia/Manila  Wed May 10 15:56:00 1899 UT = Wed May 10 23:56:00 1899 +08 isdst=0 gmtoff=28800
Asia/Manila  Sat Oct 31 15:59:59 1936 UT = Sat Oct 31 23:59:59 1936 +08 isdst=0 gmtoff=28800
...

Obviously a low-priority issue, since it's more than 100 years ago, but 
still would be nice to know why we have a problem.  It's not totally out 
of the realm of probability that someone will move the dateline again, 
perhaps if the UTC+14 parts of Kiribati were to separate from the rest 
of the country?  :)

Data gathered on a NetBSD 7.99.64 system running on amd64 hardware, and 
using the 2017a tzdata.  I think we're still running 2016i version of 
tzcode.

So the question(s):
 	* is zdump wrong?
 	* is the compiled data file wrong?
 	* (most likely) am I just misinterpreting the data?
 	* is this something that has already been fixed in a
 	  more recent tzcode release?



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| Paul Goyette     | PGP Key fingerprint:     | E-mail addresses:      |
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