On Mon, 14 Jul 2025 at 11:08, Björn Schäpers <g...@hazardy.de> wrote:
>
> Am 14.07.2025 um 10:20 schrieb Tomasz Kaminski:
> >
> >
> > On Tue, Jul 8, 2025 at 10:48 PM Björn Schäpers <g...@hazardy.de
> > <mailto:g...@hazardy.de>> wrote:
> >
> > From: Björn Schäpers <bjo...@hazardy.de <mailto:bjo...@hazardy.de>>
> >
> > I have based this on my previous (not yet landed) patch, but it only
> > reuses the #ifdef to include <array>. Since std::array isn't used
> > anywhere else I thought that was the right place to put it.
> >
> > I hope the formatting is okay.
> >
> > I've used wide strings for the Windows zone name and territory, since
> > the Windows API returns wide strings and thus they can be compared
> > directly. For the territory there exists a narrow string API, but
> > internally it calls the wide string version and narrows it down. If
> > desired I can switch to narrow strings, the conversion can be done by
> > static_cast per character since only ASCII chars are used.
> >
> > -- >8 --
> > On Windows there is no API to get the current time zone as IANA name,
> > instead Windows has its own zones. But there exists a mapping provided
> > by the Unicode Consortium. This patch adds a script to convert the XML
> > file with the mapping to a lookup table and adds a Windows code path to
> > use that mapping.
> >
> > libstdc++-v3/Changelog:
> >
> > Implement std::chrono::current_zone() for Windows
> >
> > * include/bits/windows_zones-map.h: New file, contains the look
> > up table.
> > * scripts/gen_windows_zones_map.py: New file, generates
> > windows_zones-map.h.
> > * src/c++20/tzdb.cc (tzdb::current_zone): Add Windows code
> > path.
> >
> > Signed-off-by: Björn Schäpers <bjo...@hazardy.de
> > <mailto:bjo...@hazardy.de>>
> > ---
> > libstdc++-v3/include/bits/windows_zones-map.h | 407 ++++++++++++++++++
> > libstdc++-v3/scripts/gen_windows_zones_map.py | 128 ++++++
> > libstdc++-v3/src/c++20/tzdb.cc | 102 ++++-
> > 3 files changed, 635 insertions(+), 2 deletions(-)
> > create mode 100644 libstdc++-v3/include/bits/windows_zones-map.h
> > create mode 100644 libstdc++-v3/scripts/gen_windows_zones_map.py
> >
> > diff --git a/libstdc++-v3/include/bits/windows_zones-map.h
> > b/libstdc++-v3/
> > include/bits/windows_zones-map.h
> > new file mode 100644
> > index 00000000000..7be736b063d
> > --- /dev/null
> > +++ b/libstdc++-v3/include/bits/windows_zones-map.h
> > @@ -0,0 +1,407 @@
> > +// Generated by scripts/gen_windows_zones_map.py, do not edit.
> > +
> > +// Copyright The GNU Toolchain Authors.
> > +//
> > +// This file is part of the GNU ISO C++ Library. This library is free
> > +// software; you can redistribute it and/or modify it under the
> > +// terms of the GNU General Public License as published by the
> > +// Free Software Foundation; either version 3, or (at your option)
> > +// any later version.
> > +
> > +// This library is distributed in the hope that it will be useful,
> > +// but WITHOUT ANY WARRANTY; without even the implied warranty of
> > +// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
> > +// GNU General Public License for more details.
> > +
> > +// Under Section 7 of GPL version 3, you are granted additional
> > +// permissions described in the GCC Runtime Library Exception, version
> > +// 3.1, as published by the Free Software Foundation.
> > +
> > +// You should have received a copy of the GNU General Public License
> > and
> > +// a copy of the GCC Runtime Library Exception along with this program;
> > +// see the files COPYING3 and COPYING.RUNTIME respectively. If not,
> > see
> > +// <http://www.gnu.org/licenses/ <http://www.gnu.org/licenses/>>.
> > +
> > +/** @file bits/windows_zones-map.h
> > + * This is an internal header file, included by other library headers.
> > + * Do not attempt to use it directly. @headername{chrono}
> > + */
> > +
> > +#ifndef _GLIBCXX_GET_WINDOWS_ZONES_MAP
> > +# error "This is not a public header, do not include it directly"
> > +#endif
> > +
> > +struct windows_zone_map_entry
> > +{
> > + wstring_view windows_name;
> > + wstring_view territory;
> > + string_view iana_name;
> > +};
> > +
> > +static constexpr array<windows_zone_map_entry, 361> windows_zone_map{
> > + {
> > + {L"AUS Central Standard Time", L"001", "Australia/Darwin"},
> > + {L"AUS Eastern Standard Time", L"001", "Australia/Sydney"},
> > + {L"Afghanistan Standard Time", L"001", "Asia/Kabul"},
> > + {L"Alaskan Standard Time", L"001", "America/Anchorage"},
> > + {L"Aleutian Standard Time", L"001", "America/Adak"},
> > + {L"Altai Standard Time", L"001", "Asia/Barnaul"},
> > + {L"Arab Standard Time", L"001", "Asia/Riyadh"},
> > + {L"Arab Standard Time", L"BH", "Asia/Bahrain"},
> > + {L"Arab Standard Time", L"KW", "Asia/Kuwait"},
> > + {L"Arab Standard Time", L"QA", "Asia/Qatar"},
> > + {L"Arab Standard Time", L"YE", "Asia/Aden"},
> > + {L"Arabian Standard Time", L"001", "Asia/Dubai"},
> > + {L"Arabian Standard Time", L"OM", "Asia/Muscat"},
> > + {L"Arabian Standard Time", L"ZZ", "Etc/GMT-4"},
> > + {L"Arabic Standard Time", L"001", "Asia/Baghdad"},
> > + {L"Argentina Standard Time", L"001", "America/Buenos_Aires"},
> > + {L"Astrakhan Standard Time", L"001", "Europe/Astrakhan"},
> > + {L"Atlantic Standard Time", L"001", "America/Halifax"},
> > + {L"Atlantic Standard Time", L"BM", "Atlantic/Bermuda"},
> > + {L"Atlantic Standard Time", L"GL", "America/Thule"},
> > + {L"Aus Central W. Standard Time", L"001", "Australia/Eucla"},
> > + {L"Azerbaijan Standard Time", L"001", "Asia/Baku"},
> > + {L"Azores Standard Time", L"001", "Atlantic/Azores"},
> > + {L"Azores Standard Time", L"GL", "America/Scoresbysund"},
> > + {L"Bahia Standard Time", L"001", "America/Bahia"},
> > + {L"Bangladesh Standard Time", L"001", "Asia/Dhaka"},
> > + {L"Bangladesh Standard Time", L"BT", "Asia/Thimphu"},
> > + {L"Belarus Standard Time", L"001", "Europe/Minsk"},
> > + {L"Bougainville Standard Time", L"001", "Pacific/Bougainville"},
> > + {L"Canada Central Standard Time", L"001", "America/Regina"},
> > + {L"Cape Verde Standard Time", L"001", "Atlantic/Cape_Verde"},
> > + {L"Cape Verde Standard Time", L"ZZ", "Etc/GMT+1"},
> > + {L"Caucasus Standard Time", L"001", "Asia/Yerevan"},
> > + {L"Cen. Australia Standard Time", L"001", "Australia/Adelaide"},
> > + {L"Central America Standard Time", L"001", "America/Guatemala"},
> > + {L"Central America Standard Time", L"BZ", "America/Belize"},
> > + {L"Central America Standard Time", L"CR", "America/Costa_Rica"},
> > + {L"Central America Standard Time", L"EC", "Pacific/Galapagos"},
> > + {L"Central America Standard Time", L"HN", "America/Tegucigalpa"},
> > + {L"Central America Standard Time", L"NI", "America/Managua"},
> > + {L"Central America Standard Time", L"SV", "America/El_Salvador"},
> > + {L"Central America Standard Time", L"ZZ", "Etc/GMT+6"},
> > + {L"Central Asia Standard Time", L"001", "Asia/Bishkek"},
> > + {L"Central Asia Standard Time", L"AQ", "Antarctica/Vostok"},
> > + {L"Central Asia Standard Time", L"CN", "Asia/Urumqi"},
> > + {L"Central Asia Standard Time", L"IO", "Indian/Chagos"},
> > + {L"Central Asia Standard Time", L"ZZ", "Etc/GMT-6"},
> > + {L"Central Brazilian Standard Time", L"001", "America/Cuiaba"},
> > + {L"Central Europe Standard Time", L"001", "Europe/Budapest"},
> > + {L"Central Europe Standard Time", L"AL", "Europe/Tirane"},
> > + {L"Central Europe Standard Time", L"CZ", "Europe/Prague"},
> > + {L"Central Europe Standard Time", L"ME", "Europe/Podgorica"},
> > + {L"Central Europe Standard Time", L"RS", "Europe/Belgrade"},
> > + {L"Central Europe Standard Time", L"SI", "Europe/Ljubljana"},
> > + {L"Central Europe Standard Time", L"SK", "Europe/Bratislava"},
> > + {L"Central European Standard Time", L"001", "Europe/Warsaw"},
> > + {L"Central European Standard Time", L"BA", "Europe/Sarajevo"},
> > + {L"Central European Standard Time", L"HR", "Europe/Zagreb"},
> > + {L"Central European Standard Time", L"MK", "Europe/Skopje"},
> > + {L"Central Pacific Standard Time", L"001", "Pacific/Guadalcanal"},
> > + {L"Central Pacific Standard Time", L"AQ", "Antarctica/Casey"},
> > + {L"Central Pacific Standard Time", L"FM", "Pacific/Ponape"},
> > + {L"Central Pacific Standard Time", L"NC", "Pacific/Noumea"},
> > + {L"Central Pacific Standard Time", L"VU", "Pacific/Efate"},
> > + {L"Central Pacific Standard Time", L"ZZ", "Etc/GMT-11"},
> > + {L"Central Standard Time", L"001", "America/Chicago"},
> > + {L"Central Standard Time", L"CA", "America/Winnipeg"},
> > + {L"Central Standard Time", L"MX", "America/Matamoros"},
> > + {L"Central Standard Time (Mexico)", L"001", "America/Mexico_City"},
> > + {L"Chatham Islands Standard Time", L"001", "Pacific/Chatham"},
> > + {L"China Standard Time", L"001", "Asia/Shanghai"},
> > + {L"China Standard Time", L"HK", "Asia/Hong_Kong"},
> > + {L"China Standard Time", L"MO", "Asia/Macau"},
> > + {L"Cuba Standard Time", L"001", "America/Havana"},
> > + {L"Dateline Standard Time", L"001", "Etc/GMT+12"},
> > + {L"E. Africa Standard Time", L"001", "Africa/Nairobi"},
> > + {L"E. Africa Standard Time", L"AQ", "Antarctica/Syowa"},
> > + {L"E. Africa Standard Time", L"DJ", "Africa/Djibouti"},
> > + {L"E. Africa Standard Time", L"ER", "Africa/Asmera"},
> > + {L"E. Africa Standard Time", L"ET", "Africa/Addis_Ababa"},
> > + {L"E. Africa Standard Time", L"KM", "Indian/Comoro"},
> > + {L"E. Africa Standard Time", L"MG", "Indian/Antananarivo"},
> > + {L"E. Africa Standard Time", L"SO", "Africa/Mogadishu"},
> > + {L"E. Africa Standard Time", L"TZ", "Africa/Dar_es_Salaam"},
> > + {L"E. Africa Standard Time", L"UG", "Africa/Kampala"},
> > + {L"E. Africa Standard Time", L"YT", "Indian/Mayotte"},
> > + {L"E. Africa Standard Time", L"ZZ", "Etc/GMT-3"},
> > + {L"E. Australia Standard Time", L"001", "Australia/Brisbane"},
> > + {L"E. Europe Standard Time", L"001", "Europe/Chisinau"},
> > + {L"E. South America Standard Time", L"001", "America/Sao_Paulo"},
> > + {L"Easter Island Standard Time", L"001", "Pacific/Easter"},
> > + {L"Eastern Standard Time", L"001", "America/New_York"},
> > + {L"Eastern Standard Time", L"BS", "America/Nassau"},
> > + {L"Eastern Standard Time", L"CA", "America/Toronto"},
> > + {L"Eastern Standard Time (Mexico)", L"001", "America/Cancun"},
> > + {L"Egypt Standard Time", L"001", "Africa/Cairo"},
> > + {L"Ekaterinburg Standard Time", L"001", "Asia/Yekaterinburg"},
> > + {L"FLE Standard Time", L"001", "Europe/Kiev"},
> > + {L"FLE Standard Time", L"AX", "Europe/Mariehamn"},
> > + {L"FLE Standard Time", L"BG", "Europe/Sofia"},
> > + {L"FLE Standard Time", L"EE", "Europe/Tallinn"},
> > + {L"FLE Standard Time", L"FI", "Europe/Helsinki"},
> > + {L"FLE Standard Time", L"LT", "Europe/Vilnius"},
> > + {L"FLE Standard Time", L"LV", "Europe/Riga"},
> > + {L"Fiji Standard Time", L"001", "Pacific/Fiji"},
> > + {L"GMT Standard Time", L"001", "Europe/London"},
> > + {L"GMT Standard Time", L"ES", "Atlantic/Canary"},
> > + {L"GMT Standard Time", L"FO", "Atlantic/Faeroe"},
> > + {L"GMT Standard Time", L"GG", "Europe/Guernsey"},
> > + {L"GMT Standard Time", L"IE", "Europe/Dublin"},
> > + {L"GMT Standard Time", L"IM", "Europe/Isle_of_Man"},
> > + {L"GMT Standard Time", L"JE", "Europe/Jersey"},
> > + {L"GMT Standard Time", L"PT", "Europe/Lisbon"},
> > + {L"GTB Standard Time", L"001", "Europe/Bucharest"},
> > + {L"GTB Standard Time", L"CY", "Asia/Nicosia"},
> > + {L"GTB Standard Time", L"GR", "Europe/Athens"},
> > + {L"Georgian Standard Time", L"001", "Asia/Tbilisi"},
> > + {L"Greenland Standard Time", L"001", "America/Godthab"},
> > + {L"Greenwich Standard Time", L"001", "Atlantic/Reykjavik"},
> > + {L"Greenwich Standard Time", L"BF", "Africa/Ouagadougou"},
> > + {L"Greenwich Standard Time", L"CI", "Africa/Abidjan"},
> > + {L"Greenwich Standard Time", L"GH", "Africa/Accra"},
> > + {L"Greenwich Standard Time", L"GL", "America/Danmarkshavn"},
> > + {L"Greenwich Standard Time", L"GM", "Africa/Banjul"},
> > + {L"Greenwich Standard Time", L"GN", "Africa/Conakry"},
> > + {L"Greenwich Standard Time", L"GW", "Africa/Bissau"},
> > + {L"Greenwich Standard Time", L"LR", "Africa/Monrovia"},
> > + {L"Greenwich Standard Time", L"ML", "Africa/Bamako"},
> > + {L"Greenwich Standard Time", L"MR", "Africa/Nouakchott"},
> > + {L"Greenwich Standard Time", L"SH", "Atlantic/St_Helena"},
> > + {L"Greenwich Standard Time", L"SL", "Africa/Freetown"},
> > + {L"Greenwich Standard Time", L"SN", "Africa/Dakar"},
> > + {L"Greenwich Standard Time", L"TG", "Africa/Lome"},
> > + {L"Haiti Standard Time", L"001", "America/Port-au-Prince"},
> > + {L"Hawaiian Standard Time", L"001", "Pacific/Honolulu"},
> > + {L"Hawaiian Standard Time", L"CK", "Pacific/Rarotonga"},
> > + {L"Hawaiian Standard Time", L"PF", "Pacific/Tahiti"},
> > + {L"Hawaiian Standard Time", L"ZZ", "Etc/GMT+10"},
> > + {L"India Standard Time", L"001", "Asia/Calcutta"},
> > + {L"Iran Standard Time", L"001", "Asia/Tehran"},
> > + {L"Israel Standard Time", L"001", "Asia/Jerusalem"},
> > + {L"Jordan Standard Time", L"001", "Asia/Amman"},
> > + {L"Kaliningrad Standard Time", L"001", "Europe/Kaliningrad"},
> > + {L"Korea Standard Time", L"001", "Asia/Seoul"},
> > + {L"Libya Standard Time", L"001", "Africa/Tripoli"},
> > + {L"Line Islands Standard Time", L"001", "Pacific/Kiritimati"},
> > + {L"Line Islands Standard Time", L"ZZ", "Etc/GMT-14"},
> > + {L"Lord Howe Standard Time", L"001", "Australia/Lord_Howe"},
> > + {L"Magadan Standard Time", L"001", "Asia/Magadan"},
> > + {L"Magallanes Standard Time", L"001", "America/Punta_Arenas"},
> > + {L"Marquesas Standard Time", L"001", "Pacific/Marquesas"},
> > + {L"Mauritius Standard Time", L"001", "Indian/Mauritius"},
> > + {L"Mauritius Standard Time", L"RE", "Indian/Reunion"},
> > + {L"Mauritius Standard Time", L"SC", "Indian/Mahe"},
> > + {L"Middle East Standard Time", L"001", "Asia/Beirut"},
> > + {L"Montevideo Standard Time", L"001", "America/Montevideo"},
> > + {L"Morocco Standard Time", L"001", "Africa/Casablanca"},
> > + {L"Morocco Standard Time", L"EH", "Africa/El_Aaiun"},
> > + {L"Mountain Standard Time", L"001", "America/Denver"},
> > + {L"Mountain Standard Time", L"CA", "America/Edmonton"},
> > + {L"Mountain Standard Time", L"MX", "America/Ciudad_Juarez"},
> > + {L"Mountain Standard Time (Mexico)", L"001", "America/Mazatlan"},
> > + {L"Myanmar Standard Time", L"001", "Asia/Rangoon"},
> > + {L"Myanmar Standard Time", L"CC", "Indian/Cocos"},
> > + {L"N. Central Asia Standard Time", L"001", "Asia/Novosibirsk"},
> > + {L"Namibia Standard Time", L"001", "Africa/Windhoek"},
> > + {L"Nepal Standard Time", L"001", "Asia/Katmandu"},
> > + {L"New Zealand Standard Time", L"001", "Pacific/Auckland"},
> > + {L"New Zealand Standard Time", L"AQ", "Antarctica/McMurdo"},
> > + {L"Newfoundland Standard Time", L"001", "America/St_Johns"},
> > + {L"Norfolk Standard Time", L"001", "Pacific/Norfolk"},
> > + {L"North Asia East Standard Time", L"001", "Asia/Irkutsk"},
> > + {L"North Asia Standard Time", L"001", "Asia/Krasnoyarsk"},
> > + {L"North Korea Standard Time", L"001", "Asia/Pyongyang"},
> > + {L"Omsk Standard Time", L"001", "Asia/Omsk"},
> > + {L"Pacific SA Standard Time", L"001", "America/Santiago"},
> > + {L"Pacific Standard Time", L"001", "America/Los_Angeles"},
> > + {L"Pacific Standard Time", L"CA", "America/Vancouver"},
> > + {L"Pacific Standard Time (Mexico)", L"001", "America/Tijuana"},
> > + {L"Pakistan Standard Time", L"001", "Asia/Karachi"},
> > + {L"Paraguay Standard Time", L"001", "America/Asuncion"},
> > + {L"Qyzylorda Standard Time", L"001", "Asia/Qyzylorda"},
> > + {L"Romance Standard Time", L"001", "Europe/Paris"},
> > + {L"Romance Standard Time", L"BE", "Europe/Brussels"},
> > + {L"Romance Standard Time", L"DK", "Europe/Copenhagen"},
> > + {L"Romance Standard Time", L"ES", "Europe/Madrid"},
> > + {L"Russia Time Zone 10", L"001", "Asia/Srednekolymsk"},
> > + {L"Russia Time Zone 11", L"001", "Asia/Kamchatka"},
> > + {L"Russia Time Zone 3", L"001", "Europe/Samara"},
> > + {L"Russian Standard Time", L"001", "Europe/Moscow"},
> > + {L"Russian Standard Time", L"UA", "Europe/Simferopol"},
> > + {L"SA Eastern Standard Time", L"001", "America/Cayenne"},
> > + {L"SA Eastern Standard Time", L"AQ", "Antarctica/Rothera"},
> > + {L"SA Eastern Standard Time", L"BR", "America/Fortaleza"},
> > + {L"SA Eastern Standard Time", L"FK", "Atlantic/Stanley"},
> > + {L"SA Eastern Standard Time", L"SR", "America/Paramaribo"},
> > + {L"SA Eastern Standard Time", L"ZZ", "Etc/GMT+3"},
> > + {L"SA Pacific Standard Time", L"001", "America/Bogota"},
> > + {L"SA Pacific Standard Time", L"BR", "America/Rio_Branco"},
> > + {L"SA Pacific Standard Time", L"CA", "America/Coral_Harbour"},
> > + {L"SA Pacific Standard Time", L"EC", "America/Guayaquil"},
> > + {L"SA Pacific Standard Time", L"JM", "America/Jamaica"},
> > + {L"SA Pacific Standard Time", L"KY", "America/Cayman"},
> > + {L"SA Pacific Standard Time", L"PA", "America/Panama"},
> > + {L"SA Pacific Standard Time", L"PE", "America/Lima"},
> > + {L"SA Pacific Standard Time", L"ZZ", "Etc/GMT+5"},
> > + {L"SA Western Standard Time", L"001", "America/La_Paz"},
> > + {L"SA Western Standard Time", L"AG", "America/Antigua"},
> > + {L"SA Western Standard Time", L"AI", "America/Anguilla"},
> > + {L"SA Western Standard Time", L"AW", "America/Aruba"},
> > + {L"SA Western Standard Time", L"BB", "America/Barbados"},
> > + {L"SA Western Standard Time", L"BL", "America/St_Barthelemy"},
> > + {L"SA Western Standard Time", L"BQ", "America/Kralendijk"},
> > + {L"SA Western Standard Time", L"BR", "America/Manaus"},
> > + {L"SA Western Standard Time", L"CA", "America/Blanc-Sablon"},
> > + {L"SA Western Standard Time", L"CW", "America/Curacao"},
> > + {L"SA Western Standard Time", L"DM", "America/Dominica"},
> > + {L"SA Western Standard Time", L"DO", "America/Santo_Domingo"},
> > + {L"SA Western Standard Time", L"GD", "America/Grenada"},
> > + {L"SA Western Standard Time", L"GP", "America/Guadeloupe"},
> > + {L"SA Western Standard Time", L"GY", "America/Guyana"},
> > + {L"SA Western Standard Time", L"KN", "America/St_Kitts"},
> > + {L"SA Western Standard Time", L"LC", "America/St_Lucia"},
> > + {L"SA Western Standard Time", L"MF", "America/Marigot"},
> > + {L"SA Western Standard Time", L"MQ", "America/Martinique"},
> > + {L"SA Western Standard Time", L"MS", "America/Montserrat"},
> > + {L"SA Western Standard Time", L"PR", "America/Puerto_Rico"},
> > + {L"SA Western Standard Time", L"SX", "America/Lower_Princes"},
> > + {L"SA Western Standard Time", L"TT", "America/Port_of_Spain"},
> > + {L"SA Western Standard Time", L"VC", "America/St_Vincent"},
> > + {L"SA Western Standard Time", L"VG", "America/Tortola"},
> > + {L"SA Western Standard Time", L"VI", "America/St_Thomas"},
> > + {L"SA Western Standard Time", L"ZZ", "Etc/GMT+4"},
> > + {L"SE Asia Standard Time", L"001", "Asia/Bangkok"},
> > + {L"SE Asia Standard Time", L"AQ", "Antarctica/Davis"},
> > + {L"SE Asia Standard Time", L"CX", "Indian/Christmas"},
> > + {L"SE Asia Standard Time", L"ID", "Asia/Jakarta"},
> > + {L"SE Asia Standard Time", L"KH", "Asia/Phnom_Penh"},
> > + {L"SE Asia Standard Time", L"LA", "Asia/Vientiane"},
> > + {L"SE Asia Standard Time", L"VN", "Asia/Saigon"},
> > + {L"SE Asia Standard Time", L"ZZ", "Etc/GMT-7"},
> > + {L"Saint Pierre Standard Time", L"001", "America/Miquelon"},
> > + {L"Sakhalin Standard Time", L"001", "Asia/Sakhalin"},
> > + {L"Samoa Standard Time", L"001", "Pacific/Apia"},
> > + {L"Sao Tome Standard Time", L"001", "Africa/Sao_Tome"},
> > + {L"Saratov Standard Time", L"001", "Europe/Saratov"},
> > + {L"Singapore Standard Time", L"001", "Asia/Singapore"},
> > + {L"Singapore Standard Time", L"BN", "Asia/Brunei"},
> > + {L"Singapore Standard Time", L"ID", "Asia/Makassar"},
> > + {L"Singapore Standard Time", L"MY", "Asia/Kuala_Lumpur"},
> > + {L"Singapore Standard Time", L"PH", "Asia/Manila"},
> > + {L"Singapore Standard Time", L"ZZ", "Etc/GMT-8"},
> > + {L"South Africa Standard Time", L"001", "Africa/Johannesburg"},
> > + {L"South Africa Standard Time", L"BI", "Africa/Bujumbura"},
> > + {L"South Africa Standard Time", L"BW", "Africa/Gaborone"},
> > + {L"South Africa Standard Time", L"CD", "Africa/Lubumbashi"},
> > + {L"South Africa Standard Time", L"LS", "Africa/Maseru"},
> > + {L"South Africa Standard Time", L"MW", "Africa/Blantyre"},
> > + {L"South Africa Standard Time", L"MZ", "Africa/Maputo"},
> > + {L"South Africa Standard Time", L"RW", "Africa/Kigali"},
> > + {L"South Africa Standard Time", L"SZ", "Africa/Mbabane"},
> > + {L"South Africa Standard Time", L"ZM", "Africa/Lusaka"},
> > + {L"South Africa Standard Time", L"ZW", "Africa/Harare"},
> > + {L"South Africa Standard Time", L"ZZ", "Etc/GMT-2"},
> > + {L"South Sudan Standard Time", L"001", "Africa/Juba"},
> > + {L"Sri Lanka Standard Time", L"001", "Asia/Colombo"},
> > + {L"Sudan Standard Time", L"001", "Africa/Khartoum"},
> > + {L"Syria Standard Time", L"001", "Asia/Damascus"},
> > + {L"Taipei Standard Time", L"001", "Asia/Taipei"},
> > + {L"Tasmania Standard Time", L"001", "Australia/Hobart"},
> > + {L"Tocantins Standard Time", L"001", "America/Araguaina"},
> > + {L"Tokyo Standard Time", L"001", "Asia/Tokyo"},
> > + {L"Tokyo Standard Time", L"ID", "Asia/Jayapura"},
> > + {L"Tokyo Standard Time", L"PW", "Pacific/Palau"},
> > + {L"Tokyo Standard Time", L"TL", "Asia/Dili"},
> > + {L"Tokyo Standard Time", L"ZZ", "Etc/GMT-9"},
> > + {L"Tomsk Standard Time", L"001", "Asia/Tomsk"},
> > + {L"Tonga Standard Time", L"001", "Pacific/Tongatapu"},
> > + {L"Transbaikal Standard Time", L"001", "Asia/Chita"},
> > + {L"Turkey Standard Time", L"001", "Europe/Istanbul"},
> > + {L"Turks And Caicos Standard Time", L"001", "America/Grand_Turk"},
> > + {L"US Eastern Standard Time", L"001", "America/Indianapolis"},
> > + {L"US Mountain Standard Time", L"001", "America/Phoenix"},
> > + {L"US Mountain Standard Time", L"CA", "America/Creston"},
> > + {L"US Mountain Standard Time", L"MX", "America/Hermosillo"},
> > + {L"US Mountain Standard Time", L"ZZ", "Etc/GMT+7"},
> > + {L"UTC", L"001", "Etc/UTC"},
> > + {L"UTC+12", L"001", "Etc/GMT-12"},
> > + {L"UTC+12", L"KI", "Pacific/Tarawa"},
> > + {L"UTC+12", L"MH", "Pacific/Majuro"},
> > + {L"UTC+12", L"NR", "Pacific/Nauru"},
> > + {L"UTC+12", L"TV", "Pacific/Funafuti"},
> > + {L"UTC+12", L"UM", "Pacific/Wake"},
> > + {L"UTC+12", L"WF", "Pacific/Wallis"},
> > + {L"UTC+13", L"001", "Etc/GMT-13"},
> > + {L"UTC+13", L"KI", "Pacific/Enderbury"},
> > + {L"UTC+13", L"TK", "Pacific/Fakaofo"},
> > + {L"UTC-02", L"001", "Etc/GMT+2"},
> > + {L"UTC-02", L"BR", "America/Noronha"},
> > + {L"UTC-02", L"GS", "Atlantic/South_Georgia"},
> > + {L"UTC-08", L"001", "Etc/GMT+8"},
> > + {L"UTC-08", L"PN", "Pacific/Pitcairn"},
> > + {L"UTC-09", L"001", "Etc/GMT+9"},
> > + {L"UTC-09", L"PF", "Pacific/Gambier"},
> > + {L"UTC-11", L"001", "Etc/GMT+11"},
> > + {L"UTC-11", L"AS", "Pacific/Pago_Pago"},
> > + {L"UTC-11", L"NU", "Pacific/Niue"},
> > + {L"UTC-11", L"UM", "Pacific/Midway"},
> > + {L"Ulaanbaatar Standard Time", L"001", "Asia/Ulaanbaatar"},
> > + {L"Venezuela Standard Time", L"001", "America/Caracas"},
> > + {L"Vladivostok Standard Time", L"001", "Asia/Vladivostok"},
> > + {L"Volgograd Standard Time", L"001", "Europe/Volgograd"},
> > + {L"W. Australia Standard Time", L"001", "Australia/Perth"},
> > + {L"W. Central Africa Standard Time", L"001", "Africa/Lagos"},
> > + {L"W. Central Africa Standard Time", L"AO", "Africa/Luanda"},
> > + {L"W. Central Africa Standard Time", L"BJ", "Africa/Porto-Novo"},
> > + {L"W. Central Africa Standard Time", L"CD", "Africa/Kinshasa"},
> > + {L"W. Central Africa Standard Time", L"CF", "Africa/Bangui"},
> > + {L"W. Central Africa Standard Time", L"CG", "Africa/Brazzaville"},
> > + {L"W. Central Africa Standard Time", L"CM", "Africa/Douala"},
> > + {L"W. Central Africa Standard Time", L"DZ", "Africa/Algiers"},
> > + {L"W. Central Africa Standard Time", L"GA", "Africa/Libreville"},
> > + {L"W. Central Africa Standard Time", L"GQ", "Africa/Malabo"},
> > + {L"W. Central Africa Standard Time", L"NE", "Africa/Niamey"},
> > + {L"W. Central Africa Standard Time", L"TD", "Africa/Ndjamena"},
> > + {L"W. Central Africa Standard Time", L"TN", "Africa/Tunis"},
> > + {L"W. Central Africa Standard Time", L"ZZ", "Etc/GMT-1"},
> > + {L"W. Europe Standard Time", L"001", "Europe/Berlin"},
> > + {L"W. Europe Standard Time", L"AD", "Europe/Andorra"},
> > + {L"W. Europe Standard Time", L"AT", "Europe/Vienna"},
> > + {L"W. Europe Standard Time", L"CH", "Europe/Zurich"},
> > + {L"W. Europe Standard Time", L"GI", "Europe/Gibraltar"},
> > + {L"W. Europe Standard Time", L"IT", "Europe/Rome"},
> > + {L"W. Europe Standard Time", L"LI", "Europe/Vaduz"},
> > + {L"W. Europe Standard Time", L"LU", "Europe/Luxembourg"},
> > + {L"W. Europe Standard Time", L"MC", "Europe/Monaco"},
> > + {L"W. Europe Standard Time", L"MT", "Europe/Malta"},
> > + {L"W. Europe Standard Time", L"NL", "Europe/Amsterdam"},
> > + {L"W. Europe Standard Time", L"NO", "Europe/Oslo"},
> > + {L"W. Europe Standard Time", L"SE", "Europe/Stockholm"},
> > + {L"W. Europe Standard Time", L"SJ", "Arctic/Longyearbyen"},
> > + {L"W. Europe Standard Time", L"SM", "Europe/San_Marino"},
> > + {L"W. Europe Standard Time", L"VA", "Europe/Vatican"},
> > + {L"W. Mongolia Standard Time", L"001", "Asia/Hovd"},
> > + {L"West Asia Standard Time", L"001", "Asia/Tashkent"},
> > + {L"West Asia Standard Time", L"AQ", "Antarctica/Mawson"},
> > + {L"West Asia Standard Time", L"KZ", "Asia/Oral"},
> > + {L"West Asia Standard Time", L"MV", "Indian/Maldives"},
> > + {L"West Asia Standard Time", L"TF", "Indian/Kerguelen"},
> > + {L"West Asia Standard Time", L"TJ", "Asia/Dushanbe"},
> > + {L"West Asia Standard Time", L"TM", "Asia/Ashgabat"},
> > + {L"West Asia Standard Time", L"ZZ", "Etc/GMT-5"},
> > + {L"West Bank Standard Time", L"001", "Asia/Hebron"},
> > + {L"West Pacific Standard Time", L"001", "Pacific/Port_Moresby"},
> > + {L"West Pacific Standard Time", L"AQ",
> > "Antarctica/DumontDUrville"},
> > + {L"West Pacific Standard Time", L"FM", "Pacific/Truk"},
> > + {L"West Pacific Standard Time", L"GU", "Pacific/Guam"},
> > + {L"West Pacific Standard Time", L"MP", "Pacific/Saipan"},
> > + {L"West Pacific Standard Time", L"ZZ", "Etc/GMT-10"},
> > + {L"Yakutsk Standard Time", L"001", "Asia/Yakutsk"},
> > + {L"Yukon Standard Time", L"001", "America/Whitehorse"},
> > + }
> > +};
> > +
> > +#undef _GLIBCXX_GET_WINDOWS_ZONES_MAP
> > diff --git a/libstdc++-v3/scripts/gen_windows_zones_map.py
> > b/libstdc++-v3/
> > scripts/gen_windows_zones_map.py
> > new file mode 100644
> > index 00000000000..9edfe457a5f
> > --- /dev/null
> > +++ b/libstdc++-v3/scripts/gen_windows_zones_map.py
> > @@ -0,0 +1,128 @@
> > +#!/usr/bin/env python3
> > +#
> > +# Script to generate the map for libstdc++ std::chrono::current_zone
> > under
> > Windows.
> > +#
> > +# This file is part of GCC.
> > +#
> > +# GCC is free software; you can redistribute it and/or modify it under
> > +# the terms of the GNU General Public License as published by the Free
> > +# Software Foundation; either version 3, or (at your option) any later
> > +# version.
> > +#
> > +# GCC is distributed in the hope that it will be useful, but WITHOUT
> > ANY
> > +# WARRANTY; without even the implied warranty of MERCHANTABILITY or
> > +# FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
> > +# for more details.
> > +#
> > +# You should have received a copy of the GNU General Public License
> > +# along with GCC; see the file COPYING3. If not see
> > +# <http://www.gnu.org/licenses/ <http://www.gnu.org/licenses/>>.
> > +
> > +# To update the Libstdc++ static data in <bits/windows_zones-map.h>
> > download
> > +# the latest:
> > +# https://raw.githubusercontent.com/unicode-org/cldr/master/common/
> > supplemental/windowsZones.xml
> > <https://raw.githubusercontent.com/unicode-
> > org/cldr/master/common/supplemental/windowsZones.xml>
> > +# Then run this script and save the output to
> > +# include/bits/windows_zones-map.h
> > +
> > +import os
> > +import sys
> > +import xml.etree.ElementTree as et
> > +
> > +if len(sys.argv) != 2:
> > + print("Usage: %s <windows zones xml>" % sys.argv[0],
> > file=sys.stderr)
> > + sys.exit(1)
> > +
> > +self = os.path.basename(__file__)
> > +print("// Generated by scripts/{}, do not edit.".format(self))
> > +print("""
> > +// Copyright The GNU Toolchain Authors.
> > +//
> > +// This file is part of the GNU ISO C++ Library. This library is free
> > +// software; you can redistribute it and/or modify it under the
> > +// terms of the GNU General Public License as published by the
> > +// Free Software Foundation; either version 3, or (at your option)
> > +// any later version.
> > +
> > +// This library is distributed in the hope that it will be useful,
> > +// but WITHOUT ANY WARRANTY; without even the implied warranty of
> > +// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
> > +// GNU General Public License for more details.
> > +
> > +// Under Section 7 of GPL version 3, you are granted additional
> > +// permissions described in the GCC Runtime Library Exception, version
> > +// 3.1, as published by the Free Software Foundation.
> > +
> > +// You should have received a copy of the GNU General Public License
> > and
> > +// a copy of the GCC Runtime Library Exception along with this program;
> > +// see the files COPYING3 and COPYING.RUNTIME respectively. If not,
> > see
> > +// <http://www.gnu.org/licenses/ <http://www.gnu.org/licenses/>>.
> > +
> > +/** @file bits/windows_zones-map.h
> > + * This is an internal header file, included by other library headers.
> > + * Do not attempt to use it directly. @headername{chrono}
> > + */
> > +""")
> > +
> > +print("#ifndef _GLIBCXX_GET_WINDOWS_ZONES_MAP")
> > +print('# error "This is not a public header, do not include it
> > directly"')
> > +print("#endif\n")
> > +
> > +class WindowsZoneMapEntry:
> > + def __init__(self, windows, territory, iana):
> > + self.windows = windows
> > + self.territory = territory
> > + self.iana = iana
> > +
> > + def __lt__(self, other):
> > + if self.windows < other.windows:
> > + return True
> > + if self.windows > other.windows:
> > + return False
> > + return self.territory < other.territory
> > +
> > +windows_zone_map = []
> > +
> > +tree = et.parse(sys.argv[1])
> > +xml_zone_map = tree.getroot().find("windowsZones").find("mapTimezones")
> > +
> > +for entry in xml_zone_map.iter("mapZone"):
> > + iana = entry.attrib["type"]
> > + space = iana.find(" ")
> > + if space != -1:
> > + iana = iana[0:space]
> > + windows_zone_map.append(WindowsZoneMapEntry(entry.attrib["other"],
> > entry.attrib["territory"], iana))
> > +
> > +# Sort so we can use binary search on the array.
> > +windows_zone_map.sort();
> > +
> > +# Skip territories which have the same IANA zone as 001, so we can
> > reduce
> > the data.
> > +last_windows_zone = ""
> > +for entry in windows_zone_map[:]:
> > + if entry.windows != last_windows_zone:
> > + if entry.territory != "001":
> > + raise ValueError("Territory \"001\" not the first one, this
> > breaks assumptions in tzdb.cc!")
> > + last_windows_zone = entry.windows
> > + fallback_iana = entry.iana
> > + else:
> > + if entry.iana == fallback_iana:
> > + windows_zone_map.remove(entry)
> > +
> > +print("""struct windows_zone_map_entry
> > +{{
> > + wstring_view windows_name;
> > + wstring_view territory;
> > + string_view iana_name;
> > +}};
> > +
> > +static constexpr array<windows_zone_map_entry, {}> windows_zone_map{{
> > + {{""".format(len(windows_zone_map)))
> > +
> > +for entry in windows_zone_map:
> > + print(' {{L"{}", L"{}", "{}"}},'.format(entry.windows,
> > entry.territory, entry.iana))
> > +
> > +print(""" }
> > +};""")
> > +
> > +# <chrono> gives an error if this macro is left defined.
> > +# Do this last, so that the generated output is not usable unless we
> > reach
> > here.
> > +print("\n#undef _GLIBCXX_GET_WINDOWS_ZONES_MAP")
> > diff --git a/libstdc++-v3/src/c++20/tzdb.cc
> > b/libstdc++-v3/src/c++20/tzdb.cc
> > index 9923d14b7a7..bfbba077b92 100644
> > --- a/libstdc++-v3/src/c++20/tzdb.cc
> > +++ b/libstdc++-v3/src/c++20/tzdb.cc
> > @@ -48,6 +48,8 @@
> > # define WIN32_LEAN_AND_MEAN
> > # include <windows.h>
> > # include <psapi.h>
> > +
> > +# include <array>
> > #endif
> >
> > #if defined __GTHREADS && ATOMIC_POINTER_LOCK_FREE == 2
> > @@ -1768,6 +1770,98 @@ namespace std::chrono
> >
> > return nullptr; // not found
> > }
> > +
> > +#ifdef _GLIBCXX_HAVE_WINDOWS_H
> > + string_view
> > + detect_windows_zone() noexcept
> > + {
> > + DYNAMIC_TIME_ZONE_INFORMATION information{};
> > + if (GetDynamicTimeZoneInformation(&information) ==
> > TIME_ZONE_ID_INVALID)
> > + return {};
> > +
> > + constexpr SYSTEMTIME all_zero_time{};
> > + const wstring_view zone_name{ information.TimeZoneKeyName };
> > + auto equal = [](const SYSTEMTIME &lhs, const SYSTEMTIME &rhs)
> > noexcept
> > + { return memcmp(&lhs, &rhs, sizeof(SYSTEMTIME)) == 0; };
> > + // The logic is copied from icu, couldn't find the source.
> > + // Detect if DST is disabled.
> > + if (information.DynamicDaylightTimeDisabled
> > + && equal(information.StandardDate, information.DaylightDate)
> > + && ((!zone_name.empty()
> > + && equal(information.StandardDate, all_zero_time))
> > + || (zone_name.empty()
> > + && !equal(information.StandardDate, all_zero_time))))
> > + {
> > + if (information.Bias == 0)
> > + return "Etc/UTC";
> > +
> > + if (information.Bias % 60 != 0)
> > + // If the offset is not in full hours, we can't do anything
> > really.
> > + return {};
> > +
> > + const auto raw_index = information.Bias / 60;
> > +
> > + // The bias added to the local time equals UTC. And GMT+X
> > corrosponds
> > + // to UTC-X, the sign is negated. Thus we can use the hourly
> > bias as
> > + // an index into an array.
> > + if (raw_index < 0 && raw_index >= -14)
> > + {
> > + static array<string_view, 14> table{
> > + "Etc/GMT-1", "Etc/GMT-2", "Etc/GMT-3", "Etc/GMT-4",
> > + "Etc/GMT-5", "Etc/GMT-6", "Etc/GMT-7", "Etc/GMT-8",
> > + "Etc/GMT-9", "Etc/GMT-10", "Etc/GMT-11", "Etc/GMT-12",
> > + "Etc/GMT-13", "Etc/GMT-14"
> > + };
> > + return table[-raw_index - 1];
> > + }
> > + else if (raw_index > 0 && raw_index <= 12)
> > + {
> > + static array<string_view, 14> table{
> >
> > This table has size 14, but only 12 entries. I do not think there are zones
> > past +12,
> > but I believe size and entries should match.
>
> That is totally correct and this a classic copy and paste error.
> @Jonathan: Should I correct that (and the other things you mentioned), or are
> you doing that?
I can do it before I push it (probably later today).
>
> >
> > + "Etc/GMT+1", "Etc/GMT+2", "Etc/GMT+3", "Etc/GMT+4",
> > + "Etc/GMT+5", "Etc/GMT+6", "Etc/GMT+7", "Etc/GMT+8",
> > + "Etc/GMT+9", "Etc/GMT+10", "Etc/GMT+11", "Etc/GMT+12"
> > + };
> > + return table[raw_index - 1];
> > + }
> > + return {};
> > + }
> > +
> > +#define _GLIBCXX_GET_WINDOWS_ZONES_MAP
> > +#include <bits/windows_zones-map.h>
> > +#ifdef _GLIBCXX_GET_WINDOWS_ZONES_MAP
> > +# error "Invalid windows_zones map"
> > +#endif
> > +
> > + const auto zone_range
> > + = ranges::equal_range(windows_zone_map, zone_name, {},
> > + &windows_zone_map_entry::windows_name);
> > +
> > + const auto size = ranges::size(zone_range);
> > + if (size == 0)
> > + // Unknown zone, we can't detect anything.
> > + return {};
> > +
> > + if (size == 1)
> > + // Some zones have only one territory, use the quick path.
> > + return zone_range.front().iana_name;
> > +
> > + const auto geo_id = GetUserGeoID(GEOCLASS_NATION);
> > + wstring territory;
> > + territory.resize(2); // The terminating zero is always added on
> > top.
> > + if (GetGeoInfoW(geo_id, GEO_ISO2, territory.data(), 3, 0) == 0)
> > + // Couldn't detect the territory, fallback to "001", which is
> > the first
> > + // entry.
> > + return zone_range.front().iana_name;
> > +
> > + const auto iter = ranges::lower_bound(
> > + zone_range, territory, {},
> > &windows_zone_map_entry::territory);
> > + if (iter == zone_range.end() || iter->territory != territory)
> > + // Territory not within the the map, use "001".
> > + return zone_range.front().iana_name;
> > +
> > + return iter->iana_name;
> > + }
> > +#endif
> > } // namespace
> >
> > // Implementation of std::chrono::tzdb::locate_zone(string_view).
> > @@ -1790,7 +1884,7 @@ namespace std::chrono
> > {
> > // TODO cache this function's result?
> >
> > -#ifndef _AIX
> > +#if !defined(_AIX) && !defined(_GLIBCXX_HAVE_WINDOWS_H)
> > // Repeat the preprocessor condition used by
> > filesystem::read_symlink,
> > // to avoid a dependency on src/c++17/fs_ops.o if it won't work
> > anyway.
> > #if defined(_GLIBCXX_HAVE_READLINK) &&
> > defined(_GLIBCXX_HAVE_SYS_STAT_H)
> > @@ -1847,7 +1941,11 @@ namespace std::chrono
> > return tz;
> > }
> > }
> > -#else
> > +#elif defined(_GLIBCXX_HAVE_WINDOWS_H)
> > + if (auto tz
> > + = do_locate_zone(this->zones, this->links,
> > detect_windows_zone()))
> > + return tz;
> > +#else // defined(_AIX)
> > // AIX stores current zone in $TZ in /etc/environment but the
> > value
> > // is typically a POSIX time zone name, not IANA zone.
> > // https://developer.ibm.com/articles/au-aix-posix/ <https://
> > developer.ibm.com/articles/au-aix-posix/>
> > --
> > 2.50.0
> >
>
