On Tue, Aug 16, 2022 at 5:23 PM Paul Eggert <eggert@cs.ucla.edu> wrote:
On 8/16/22 00:08, Bradley White wrote:
> Is the intent that the standard install and the "PACKRATDATA=backzone
> PACKRATLIST=zone.tab" install should not exhibit any differences for 1970+
> timestamps?

Yes, and you can test this by running something like the following in a
source directory. The diff command should output nothing. (The test
takes a while.) I did this sort of test before releasing 2022b.

make clean
make TOPDIR=$PWD/tza ZFLAGS=-r@0 install
./zdump -i $(awk '/^[^#]/{print $3}' zone1970.tab) >a.tzs
make clean
make TOPDIR=$PWD/tzb ZFLAGS=-r@0 \
   PACKRATDATA=backzone PACKRATLIST=zone.tab \
   install
./zdump -i $(awk '/^[^#]/{print $3}' zone1970.tab) >b.tzs
diff a.tzs b.tzs
rm -r tza tzb a.tzs b.tzs

That seems to only consider zones in "zone1970.tab", which, by definition, are the zones "where civil timestamps have agreed since 1970."

What about examples like ...

$ TZ=<path-to-standard>/Africa/Freetown date -d @1660625107
Tue Aug 16 04:45:07 GMT 2022
$ TZ=<path-to-packrat>/Africa/Freetown date -d @1660625107
Tue Aug 16 05:05:07 +01 2022


and ...

$ TZ=<path-to-standard>/Pacific/Saipan date -d @230659200
Sun Apr 24 03:00:00 GDT 1977
$ TZ=<path-to-packrat>/Pacific/Saipan date -d @230659200
Sun Apr 24 02:00:00 +10 1977


It sure seems like those post-1970 timestamps are receiving different treatments (abbreviations notwithstanding).