Sync our copy of the timezone library with IANA release tzcode2018f.
About half of this is purely cosmetic changes to reduce the diff between
our code and theirs, like inserting "const" markers where they have them.
The other half is tracking actual code changes in zic.c and localtime.c.
I don't think any of these represent near-term compatibility hazards, but
it seems best to stay up to date.
I also fixed longstanding bugs in our code for producing the
known_abbrevs.txt list, which by chance hadn't been exposed before,
but which resulted in some garbage output after applying the upstream
changes in zic.c. Notably, because upstream removed their old phony
transitions at the Big Bang, it's now necessary to cope with TZif files
containing no DST transition times at all.
Branch
------
REL9_4_STABLE
Details
-------
https://git.postgresql.org/pg/commitdiff/0fead87601e5a9a4d22da738381ca558a4506114
Modified Files
--------------
src/timezone/README | 2 +-
src/timezone/localtime.c | 126 ++++++++++++------
src/timezone/pgtz.h | 16 ++-
src/timezone/private.h | 3 +
src/timezone/strftime.c | 10 +-
src/timezone/tzfile.h | 7 +-
src/timezone/zic.c | 330 ++++++++++++++++++++++++++---------------------
7 files changed, 294 insertions(+), 200 deletions(-)