May 2024 - tz - lists.iana.org

(no subject)
by Cool Gab19 05 Sep '24

05 Sep '24

can you add Philippine Daylight Time on your Database I think it was missing from the list of the time zones please reply immediately if solved thanks...

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Re: [tz] Time for a Lunar time zone? -Brooks
by Paul Eggert 11 Jul '24

11 Jul '24

On 3/2/23 09:51, Brooks Harris wrote: > Will we need DST on the Moon? :-) I hope not! The Moon's axis tilts only 1.5°, much less than the 23.5° of Earth's axis, so seasonal effects on sunlight duration are much less intense on the Moon and there should be less need for Earth-like DST. A more pressing issue is that the length of day (including daytime and nighttime) varies more on the Moon. Local Earth days vary by at most 0.008 hours from the mean of 24 hours (this variation is due to the eccentricity of the Earth orbit and the obliquity of the ecliptic). So people who think that every local Earth day is exactly 24 hours are not far off. Local lunar days, in contrast, are roughly 29.5 ± 0.25 Earth days (again, this includes both lunar daytime and lunar nighttime). That's more slop to deal with, relatively speaking, and dealing with varying-length days could be a bit of a problem for civil time on the Moon. Presumably ESA's boffins are on top of this.....

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error Portugal 1980
by Alois Treindl 01 Jul '24

01 Jul '24

I think there is an error in TZ, regarding begin of DST in Portugal in 1980. A user of my website pointed it out. file europe has > Rule Port 1978 only - Oct 1 0:00s 0 - > Rule Port 1979 1982 - Sep lastSun 1:00s 0 - > Rule Port 1980 only - Mar lastSun 0:00s 1:00 S > Rule Port 1981 1982 - Mar lastSun 1:00s 1:00 S > Rule Port 1983 only - Mar lastSun 2:00s 1:00 S But Observatório Astronómico de Lisboa http://oal.ul.pt/hora-legal/legislacao-sobre-a-hora-legal/ has in document Tabela com a definição anual da Hora Legal portuguesa desde 1911 https://oal.ul.pt/documentos/2018/01/hl1911a2018.pdf > 1980 Hora do meridiano de Greenwich até à 1 hora do dia 6 de Abril, > instante > em que foi adiantada de 60 minutos, tendo-se regressado à hiora do meri- > diano de Greenwich às 2 horas do dia 28 de Setembro (Portaria nº 69/80) > I attach a patch file

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[PROPOSED] difftime isn’t pure either
by Paul Eggert 28 May '24

28 May '24

See <https://sourceware.org/bugzilla/show_bug.cgi?id=31808#c1>. * private.h (difftime): No longer pure. --- private.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/private.h b/private.h index cacbe444..0c91a252 100644 --- a/private.h +++ b/private.h @@ -702,7 +702,7 @@ DEPRECATED_IN_C23 char *ctime(time_t const *); char *asctime_r(struct tm const *restrict, char *restrict); char *ctime_r(time_t const *, char *); #endif -ATTRIBUTE_PURE double difftime(time_t, time_t); +double difftime(time_t, time_t); size_t strftime(char *restrict, size_t, char const *restrict, struct tm const *restrict); # if HAVE_STRFTIME_L -- 2.45.1

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Unicode CLDR supplemental/windowsZones.xml update? -Brooks Harris
by Brooks Harris 28 May '24

28 May '24

Does someone know if the Unicode CLDR ../supplemental/windowsZones.xml has been updated? Following the best links I know to find: Unicode CLDR Overview https://cldr.unicode.org/index/downloads/cldr-45 Downloads https://cldr.unicode.org/index/downloads GitHub Tag https://raw.githubusercontent.com/RobThree/TimeZoneMapper/master/TimeZoneMa… This file says it corresponds with TzDb 2021a. Yet other notes say Windows zone were updated to TzDb 2024a: CLDR 45 Release Note https://cldr.unicode.org/index/downloads/cldr-45 Timezones Deprecating timezones that are no longer in zone.tab (America/Nipigon, ...) New Windows timezone mappings Was this file not actually updated or am I looking in the wrong place? Thanks, -Brooks

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[PROPOSED 1/4] More updates to GCC_DEBUG_FLAGS for GCC 14
by Paul Eggert 27 May '24

27 May '24

* Makefile (GCC_DEBUG_FLAGS): Omit -fno-common, as it is now the default. Omit -Wuninitialized as it’s implied by -Wall. Omit -Wno-address and -Wno-type-limits as they don’t seem to be needed with GCC 14. --- Makefile | 7 +++---- 1 file changed, 3 insertions(+), 4 deletions(-) diff --git a/Makefile b/Makefile index 6b093013..4d2ac1cf 100644 --- a/Makefile +++ b/Makefile @@ -313,7 +313,7 @@ GCC_INSTRUMENT = \ -fsanitize=undefined -fsanitize-address-use-after-scope \ -fsanitize-undefined-trap-on-error -fstack-protector # Omit -fanalyzer from GCC_DEBUG_FLAGS, as it makes GCC too slow. -GCC_DEBUG_FLAGS = -DGCC_LINT -g3 -O3 -fno-common \ +GCC_DEBUG_FLAGS = -DGCC_LINT -g3 -O3 \ $(GCC_INSTRUMENT) \ -Wall -Wextra \ -Walloc-size-larger-than=100000 -Warray-bounds=2 \ @@ -332,10 +332,9 @@ GCC_DEBUG_FLAGS = -DGCC_LINT -g3 -O3 -fno-common \ -Wsuggest-attribute=const -Wsuggest-attribute=format \ -Wsuggest-attribute=malloc \ -Wsuggest-attribute=noreturn -Wsuggest-attribute=pure \ - -Wtrampolines -Wundef -Wuninitialized -Wunused-macros -Wuse-after-free=3 \ + -Wtrampolines -Wundef -Wunused-macros -Wuse-after-free=3 \ -Wvariadic-macros -Wvla -Wwrite-strings \ - -Wno-address -Wno-format-nonliteral -Wno-sign-compare \ - -Wno-type-limits + -Wno-format-nonliteral -Wno-sign-compare # # If your system has a "GMT offset" field in its "struct tm"s # (or if you decide to add such a field in your system's "time.h" file), -- 2.43.0

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Re: [tz] Unicode CLDR supplemental/windowsZones.xml update? -Brooks Harris
by Paul Eggert 27 May '24

27 May '24

On 2024-05-26 12:44, Brooks Harris wrote: > Hi Pail, > On 2024-05-26 03:37 PM, Paul Eggert wrote: >> On 2024-05-26 12:30, Brooks Harris via tz wrote: >>> What is the best procedure to obtain the latest windowsZones.xml? >> >> https://github.com/unicode-org/cldr/blob/main/common/supplemental/windowsZo… > > This file is identical to the old one I have and does not reflect the > commits you referred me to. That's not a file, it's a bunch of info about the file. The info includes the file contents and a bunch of other stuff. If you just want the file, click the Raw button. >>> Is there a record of earlier versions? >> https://github.com/unicode-org/cldr/commits/main/common/supplemental/window… >> >> These are reachable from the earlier URL I emailed. > > Right, but no version of windowsZones.xml I can find has those commits > applied. ? Those changes are visible to me via that URL. Anyway, try clicking the "Raw" button. It should give you this URL: https://raw.githubusercontent.com/unicode-org/cldr/main/common/supplemental… and I see the changes there too.

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[PROPOSED 1/4] Update GCC_DEBUG_FLAGS for GCC 14
by Paul Eggert 25 May '24

25 May '24

* Makefile (GCC_DEBUG_FLAGS): Add -Wflex-array-member-not-at-end, -Wmissing-variable-declarations. --- Makefile | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/Makefile b/Makefile index 3f550b3f..a72fb2ea 100644 --- a/Makefile +++ b/Makefile @@ -315,10 +315,11 @@ GCC_DEBUG_FLAGS = -DGCC_LINT -g3 -O3 -fno-common \ -Walloc-size-larger-than=100000 -Warray-bounds=2 \ -Wbad-function-cast -Wbidi-chars=any,ucn -Wcast-align=strict -Wdate-time \ -Wdeclaration-after-statement -Wdouble-promotion \ - -Wduplicated-branches -Wduplicated-cond \ + -Wduplicated-branches -Wduplicated-cond -Wflex-array-member-not-at-end \ -Wformat=2 -Wformat-overflow=2 -Wformat-signedness -Wformat-truncation \ -Wimplicit-fallthrough=5 -Winit-self -Wlogical-op \ - -Wmissing-declarations -Wmissing-prototypes -Wnested-externs \ + -Wmissing-declarations -Wmissing-prototypes \ + -Wmissing-variable-declarations -Wnested-externs \ -Wnull-dereference \ -Wold-style-definition -Woverlength-strings -Wpointer-arith \ -Wshadow -Wshift-overflow=2 -Wstrict-overflow \ -- 2.45.1

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[PROPOSED] Sub-second history for Maputo and Zurich
by Paul Eggert 24 May '24

24 May '24

* africa (Africa/Maputo), europe (Europe/Zurich): Add #STDOFF comments for two zones with well-sourced standard time that was not an integral number of seconds away from UT. This does not change the TZif output files. --- africa | 5 +++-- europe | 5 +++-- 2 files changed, 6 insertions(+), 4 deletions(-) diff --git a/africa b/africa index 695d66ed..4f0d1e7b 100644 --- a/africa +++ b/africa @@ -1101,11 +1101,11 @@ Zone Africa/El_Aaiun -0:52:48 - LMT 1934 Jan # El Aaiún # Zambia # Zimbabwe # -# From Paul Eggert (2024-04-09): +# From Paul Eggert (2024-05-24): # The London Gazette, 1903-04-03, page 2245, says that # as of 1903-03-03 a time ball at the port of Lourenço Marques # (as Maputo was then called) was dropped daily at 13:00:00 LMT, -# corresponding to 22:49:41.7 GMT; round this to UT+2:10:18. +# corresponding to 22:49:41.7 GMT, so local time was +02:10:18.3. # Conversely, the newspaper South Africa, 1909-02-09, page 321, # says the port had just installed an apparatus that communicated # "from the controlling clock in the new Observatory at Reuben Point ... @@ -1116,6 +1116,7 @@ Zone Africa/El_Aaiun -0:52:48 - LMT 1934 Jan # El Aaiún # For lack of better info, list 1909 as the transition date. # # Zone NAME STDOFF RULES FORMAT [UNTIL] + #STDOFF 2:10:18.3 Zone Africa/Maputo 2:10:18 - LMT 1909 2:00 - CAT diff --git a/europe b/europe index 9ea14914..2f180e64 100644 --- a/europe +++ b/europe @@ -3486,8 +3486,8 @@ Zone Atlantic/Canary -1:01:36 - LMT 1922 Mar # Las Palmas de Gran C. # but if no one is present after 11 at night, could be postponed until one # hour before the beginning of service. -# From Paul Eggert (2013-09-11): -# Round BMT to the nearest even second, 0:29:46. +# From Paul Eggert (2024-05-24): +# Express BMT as 0:29:45.500, approximately the same precision 7° 26' 22.50". # # We can find no reliable source for Shanks's assertion that all of Switzerland # except Geneva switched to Bern Mean Time at 00:00 on 1848-09-12. This book: @@ -3526,6 +3526,7 @@ Rule Swiss 1941 1942 - May Mon>=1 1:00 1:00 S Rule Swiss 1941 1942 - Oct Mon>=1 2:00 0 - # Zone NAME STDOFF RULES FORMAT [UNTIL] Zone Europe/Zurich 0:34:08 - LMT 1853 Jul 16 # See above comment. + #STDOFF 0:29:45.500 0:29:46 - BMT 1894 Jun # Bern Mean Time 1:00 Swiss CE%sT 1981 1:00 EU CE%sT -- 2.43.0

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Deprecating POSIX Zones to Links?
by Justin Grant 23 May '24

23 May '24

Hi TZ friends - I'm one of the volunteers working on ECMAScript's time zone strategy. We had a question: of all the legacy Zone names in TZDB, why have a few of them like "WET" and "EST5EDT" been retained as Zones, while the rest of the legacy names like "GB-Eire" and "Jamaica" have all been turned into Links pointing to some other Zone? What was special about the Zones below that caused them to stay as Zones? EST MST HST EST5EDT CST6CDT MST7MDT PST8PDT WET CET MET EET Regardless of the history behind these 11 Zone names, would there be interest in accepting a PR that turns these Zones into Links? I'm asking because ECMAScript's time zone enumeration API is specified to only return Zone names, but ECMAScript implementations in Safari and Chrome have long omitted the Zones above from their enumeration API because they create redundant and confusing results for end users. We'd like to align the specification to web reality, and ideally make these changes upstream in TZDB (if that would be welcome). Here's the mappings that we're currently considering in ECMAScript. We used the TZ approach of preferring the largest city for each of the DST-using legacy Zones. Although any other mappings would be OK with us, so let me know if you think there are more appropriate mappings. EST => Etc/GMT+5 MST => Etc/GMT+7 HST => Etc/GMT+10 EST5EDT => America/New_York CST6CDT => America/Chicago MST7MDT => America/Denver PST8PDT => America/Los_Angeles WET => Europe/Lisbon CET => Europe/Berlin MET => Europe/Berlin EET => Europe/Kyiv Thanks, Justin Grant

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