ICU-59180.0.1.tar.gz

[apple/icu.git] / icuSources / tools / tzcode / icuzones

diff --git a/icuSources/tools/tzcode/icuzones b/icuSources/tools/tzcode/icuzones
index 9e3c7c9c7251288b27fcd85aecbda7618b14995d..168a86f9181d0720ca9979be271ebabc6f19f5e4 100644 (file)
--- a/icuSources/tools/tzcode/icuzones
+++ b/icuSources/tools/tzcode/icuzones
@@ -78,3 +78,52 @@ Link Asia/Ho_Chi_Minh VST
 #
 Link America/Regina Canada/East-Saskatchewan # removed from backward in 2017c
 
+
+# Note:
+#   Following section was added for tz database 2018a and 2018b.
+# ICU has a bug handling negative DST, and we also don't want to
+# flip sumer time name and winter time name for Dublin at least for
+# now. Because the change had major impacts to tz database external
+# consumers, the tz database maintainer once reverted the Europe/Dublin
+# rules (same as 2017c or older) in 2018c. The tz database maintainer
+# thinks the changes in 2018a should be brought back when external
+# tz database consumers are ready to adopt the change. We don't know
+# what CLDR TC want to do with this for now. But if tz database brings
+# back the change, and CLDR TC (and ICU TC) want to keep the display name
+# unchanged, then we can uncomment the block below to restore ICU
+# custom override. (Yoshito 2018-01-23)
+
+#
+# tzdata2018a changed Europe/Dublin to use IST (UTC+1) as the standard time
+# of the region, and GMT (UTC) as the daylight saving time with negative
+# offset (-1 hour) in winter. ICU SimpleTimeZone rejects a zone with negative
+# daylight saving time offset. We could remove the restriction in newer version
+# of ICU, but such data does not work well with older ICU runtime without
+# fixing the issue. For now, we define our own Europe/Dubin in ICU, replacing
+# Europe/Dublin data from the tz database.
+#
+
+# Rule NAME    FROM    TO      TYPE    IN      ON      AT      SAVE    LETTER/S
+# Rule Eire--ICU       1971    only    -       Oct     31       2:00u  0       GMT
+# Rule Eire--ICU       1972    1980    -       Mar     Sun>=16  2:00u  1:00    IST
+# Rule Eire--ICU       1972    1980    -       Oct     Sun>=23  2:00u  0       GMT
+# Rule Eire--ICU       1981    max     -       Mar     lastSun  1:00u  1:00    IST
+# Rule Eire--ICU       1981    1989    -       Oct     Sun>=23  1:00u  0       GMT
+# Rule Eire--ICU       1990    1995    -       Oct     Sun>=22  1:00u  0       GMT
+# Rule Eire--ICU       1996    max     -       Oct     lastSun  1:00u  0       GMT
+
+# Zone NAME            GMTOFF  RULES   FORMAT  [UNTIL]
+# Zone Europe/Dublin--ICU      -0:25:00 -      LMT     1880 Aug  2
+#                      -0:25:21 -      DMT     1916 May 21  2:00s
+#                      -0:25:21 1:00   IST     1916 Oct  1  2:00s
+#                       0:00   GB-Eire %s      1921 Dec  6 # independence
+#                       0:00   GB-Eire GMT/IST 1940 Feb 25  2:00s
+#                       0:00   1:00    IST     1946 Oct  6  2:00s
+#                       0:00   -       GMT     1947 Mar 16  2:00s
+#                       0:00   1:00    IST     1947 Nov  2  2:00s
+#                       0:00   -       GMT     1948 Apr 18  2:00s
+#                       0:00   GB-Eire GMT/IST 1968 Oct 27
+#                       0:00   Eire--ICU       GMT/IST
+
+# Link Europe/Dublin--ICU Eire--ICU
+