[tz-announce] 2022a release of tz code and data available

March 17, 2022

      The 2022a release of the tz code and data is available.

This release reflects the following changes:

   Briefly:
     Palestine will spring forward on 2022-03-27, not -03-26.
     zdump -v now outputs better failure indications.
     Bug fixes for code that reads corrupted TZif data.

   Changes to future timestamps

     Palestine will spring forward on 2022-03-27, not 2022-03-26.
     (Thanks to Heba Hamad.)  Predict future transitions for first
     Sunday >= March 25.  Additionally, predict fallbacks to be the first
     Friday on or after October 23, not October's last Friday, to be more
     consistent with recent practice.  The first differing fallback
     prediction is on 2025-10-24, not 2025-10-31.

   Changes to past timestamps

     From 1992 through spring 1996, Ukraine's DST transitions were at
     02:00 standard time, not at 01:00 UTC.  (Thanks to Alois Treindl.)

     Chile's Santiago Mean Time and its LMT precursor have been adjusted
     eastward by 1 second to align with past and present law.

   Changes to commentary

     Add several references for Chile's 1946/1947 transitions, some of
     which only affected portions of the country.

   Changes to code

     Fix bug when mktime gets confused by truncated TZif files with
     unspecified local time.  (Problem reported by Almaz Mingaleev.)

     Fix bug when 32-bit time_t code reads malformed 64-bit TZif data.
     (Problem reported by Christos Zoulas.)

     When reading a version 2 or later TZif file, the TZif reader now
     validates the version 1 header and data block only enough to skip
     over them, as recommended by RFC 8536 section 4.  Also, the TZif
     reader no longer mistakenly attempts to parse a version 1 TZIf
     file header as a TZ string.

     zdump -v now outputs "(localtime failed)" and "(gmtime failed)"
     when local time and UT cannot be determined for a timestamp.

   Changes to build procedure

     Distribution tarballs now use standard POSIX.1-1988 ustar format
     instead of GNU format.  Although the formats are almost identical
     for these tarballs, ustar headers' magic fields contain "ustar"
     instead of "ustar ", and their version fields contain "00" instead
     of " ".  The two formats are planned to diverge more significantly
     for tzdb releases after 2242-03-16 12:56:31 UTC, when the ustar
     format becomes obsolete and the tarballs switch to pax format, an
     extension of ustar.  For details about these formats, please see
     "pax - portable archive interchange", IEEE Std 1003.1-2017,

<https://pubs.opengroup.org/onlinepubs/9699919799/utilities/pax.html#tag_20_9...>.

Here are links to the release files:

   https://www.iana.org/time-zones/repository/releases/tzcode2022a.tar.gz
   https://www.iana.org/time-zones/repository/releases/tzdata2022a.tar.gz
   https://www.iana.org/time-zones/repository/releases/tzdb-2022a.tar.lz

The following convenience links are also available, although they may 
point to the previous release until the relevant caches are refreshed:

   https://www.iana.org/time-zones/repository/tzcode-latest.tar.gz
   https://www.iana.org/time-zones/repository/tzdata-latest.tar.gz
   https://www.iana.org/time-zones/repository/tzdb-latest.tar.lz

Links are also available via plain HTTP, and via FTP from 
ftp://ftp.iana.org/tz/releases with the same basenames as above.

Each release file has a GPG signature, which can be retrieved by 
appending ".asc" to the above URLs. Copies of these signatures are 
appended to this message.

This release corresponds to commit 
95ecc37d29c2f5cf711af43b0ef3a35fc2847aa1 dated 2022-03-15 23:02:01 -0700 
and tagged '2022a' in the development GitHub repository at 
<https://github.com/eggert/tz>.

Here are the SHA-512 checksums for the release files:

3f047a6f414ae3df4a3d6bb9b39a1790833d191ae48e6320ab9438cd326dc455475186a02c44e4cde96b48101ab000880919b1e0e8092aed7254443ed2c831ed 
  tzcode2022a.tar.gz
542e4559beac8fd8c4af7d08d816fd12cfe7ffcb6f20bba4ff1c20eba717749ef96e5cf599b2fe03b5b8469c0467f8cb1c893008160da281055a123dd9e810d9 
  tzdata2022a.tar.gz
ece0b7a9ad3d365f8605e8f98a8a78b7fdbbb8aa615b585f21256d9401c59845fcdc951f5fc876293f1b7956b1a2d3fa2baf85099d637a91d4199ee30cf4307e 
  tzdb-2022a.tar.lz

Here are the GPG digital signatures for the release files:

PS. If your tzdata parser does not yet support negative DST offsets or 
times past 24:00, or if it insists on a 'pacificnew' file that is no 
longer present, this release's data entries can be turned into a 
rearguard-format tarball that should work even with these older parsers. 
This is intended to be a temporary transition aid for these parsers. To 
generate a rearguard-format tarball, obtain the full distribution as 
described above, and run the command 'make rearguard_tarballs' on a 
development host. Or you can run 'make rearguard.zi' to generate a 
single file that can be fed directly to a parser that works like 'zic'.

[tz-announce] 2022a release of tz code and data available

Paul Eggert