Time Zone Database Release 2022f
Released
Downloads
| File | Description |
|---|---|
 tzdb-2022f.tar.lz (505.4kb) |
Complete Distribution (Data, Code and Extras) |
| tzdata2022f.tar.gz (426.1kb) |
Data Only Distribution |
| tzcode2022f.tar.gz (278.1kb) |
Code Only Distribution |
Release Notes
Briefly:
Mexico will no longer observe DST except near the US border.
Chihuahua moves to year-round -06 on 2022-10-30.
Fiji no longer observes DST.
Move links to 'backward'.
In vanguard form, GMT is now a Zone and Etc/GMT a link.
zic now supports links to links, and vanguard form uses this.
Simplify four Ontario zones.
Fix a Y2438 bug when reading TZif data.
Enable 64-bit time_t on 32-bit glibc platforms.
Omit large-file support when no longer needed.
In C code, use some C23 features if available.
Remove no-longer-needed workaround for Qt bug 53071.
Changes to future timestamps
Mexico will no longer observe DST after 2022, except for areas
near the US border that continue to observe US DST rules.
On 2022-10-30 at 02:00 the Mexican state of Chihuahua moves
from -07 (-06 with DST) to year-round -06, thus not changing
its clocks that day. The new law states that Chihuahua
near the US border no longer observes US DST.
(Thanks to gera for the heads-up about Chihuahua.)
Fiji will not observe DST in 2022/3. (Thanks to Shalvin Narayan.)
For now, assume DST is suspended indefinitely.
Changes to data
Move links to 'backward' to ease and simplify link maintenance.
This affects generated data only if you use 'make BACKWARD='.
GMT is now a Zone and Etc/GMT a link instead of vice versa,
as GMT is needed for leap second support whereas Etc/GMT is not.
However, this change exposes a bug in TZUpdater 2.3.2 so it is
present only in vanguard form for now.
Vanguard form now uses links to links, as zic now supports this.
Changes to past timestamps
Simplify four Ontario zones, as most of the post-1970 differences
seem to have been imaginary. (Problem reported by Chris Walton.)
Move America/Nipigon, America/Rainy_River, and America/Thunder_Bay
to 'backzone'; backward-compatibility links still work, albeit
with some different timestamps before November 2005.
Changes to code
zic now supports links to links regardless of input line order.
For example, if Australia/Sydney is a Zone, the lines
Link Australia/Canberra Australia/ACT
Link Australia/Sydney Australia/Canberra
now work correctly, even though the shell commands
ln Australia/Canberra Australia/ACT
ln Australia/Sydney Australia/Canberra
would fail because the first command attempts to use a link
Australia/Canberra that does not exist until after the second
command is executed. Previously, zic had unspecified behavior if
a Link line's target was another link, and zic often misbehaved if
a Link line's target was a later Link line.
Fix line number in zic's diagnostic for a link to a link.
Fix a bug that caused localtime to mishandle timestamps starting
in the year 2438 when reading data generated by 'zic -b fat' when
distant-future DST transitions occur at times given in standard
time or in UT, not the usual case of local time. This occurs when
the corresponding .zi Rule lines specify DST transitions with TO
columns of 'max' and AT columns that end in 's' or 'u'. The
number 2438 comes from the 32-bit limit in the year 2038, plus the
400-year Gregorian cycle. (Problem reported by Bradley White.)
On glibc 2.34 and later, which optionally supports 64-bit time_t
on platforms like x86 where time_t was traditionally 32 bits,
default time_t to 64 instead of 32 bits. This lets functions like
localtime support timestamps after the year 2038, and fixes
year-2038 problems in zic when accessing files dated after 2038.
To continue to limit time_t to 32 bits on these platforms, use
"make CFLAGS='-D_TIME_BITS=32'".
In C code, do not enable large-file support on platforms like AIX
and macOS that no longer need it now that tzcode does not use
off_t or related functions like 'stat'. Large-file support is
still enabled by default on GNU/Linux, as it is needed for 64-bit
time_t support.
In C code, prefer C23 keywords to pre-C23 macros for alignof,
bool, false, and true. Also, use the following C23 features if
available: __has_include, unreachable.
zic no longer works around Qt bug 53071, as the relevant Qt
releases have been out of support since 2019. This change affects
only fat TZif files, as thin files never had the workaround.
zdump no longer modifies the environ vector when compiled on
platforms lacking tm_zone or when compiled with -DUSE_LTZ=0.
This avoid undefined behavior on POSIX platforms.