OpenJDK / portola / portola

--- a/.hgignore	Fri Aug 23 14:25:20 2019 +0100
+++ b/.hgignore	Mon Aug 26 11:20:26 2019 +0530
@@ -5,12 +5,13 @@
 ^webrev
 ^.src-rev$
 ^.jib/
-\.DS_Store
-\.metadata/
-\.recommenders/
+(^|/)\.DS_Store
+(^|/)\.metadata/
+(^|/)\.recommenders/
 test/nashorn/script/external
 test/nashorn/lib
 NashornProfile.txt
-.*/JTreport/.*
-.*/JTwork/.*
-.*/.git/.*
+(^|/)JTreport/
+(^|/)JTwork/
+(^|/)\.git/
+^src/utils/hsdis/build/
\ No newline at end of file
--- a/.hgtags	Fri Aug 23 14:25:20 2019 +0100
+++ b/.hgtags	Mon Aug 26 11:20:26 2019 +0530
@@ -575,4 +575,11 @@
 0f1e29c77e50c7da11d83df410026392c4d1a28c jdk-14+5
 2e63fb0a885fa908a97bbb0da8d7c3de11536aca jdk-13+30
 443f7359b34d60e7821216ffc60f88b6ffe0ccdd jdk-14+6
+6a159c6c23ccd0029140ab91653442e412305ce5 jdk-13+31
 28ab01c067551ef158abaef08e154e1051ca0893 jdk-14+7
+929f37a9c35d530d4e866f6e832001aeb4cfb371 jdk-13+32
+c0023e364b6f130cb1e93747b796d8718d544db1 jdk-14+8
+9c250a7600e12bdb1e611835250af3204d4aa152 jdk-13+33
+18f189e69b29f8215a3500b875127ed4fb2d977a jdk-14+9
+ececb6dae777e622abda42c705fd984a42f46b5a jdk-14+10
+bf4c808a4488025a415f867e54c8b088417e08a0 jdk-14+11
--- a/make/CompileToolsJdk.gmk	Fri Aug 23 14:25:20 2019 +0100
+++ b/make/CompileToolsJdk.gmk	Mon Aug 26 11:20:26 2019 +0530
@@ -41,6 +41,7 @@
 BUILD_TOOLS_SRC_DIRS += \
     $(TOPDIR)/make/jdk/src/classes \
     $(BUILDTOOLS_OUTPUTDIR)/interim_cldrconverter_classes \
+    $(BUILDTOOLS_OUTPUTDIR)/interim_tzdb_classes \
     #

 $(eval $(call SetupJavaCompilation,BUILD_TOOLS_JDK, \
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/make/CopyInterimTZDB.gmk	Mon Aug 26 11:20:26 2019 +0530
@@ -0,0 +1,50 @@
+#
+# Copyright (c) 2019, Oracle and/or its affiliates. All rights reserved.
+# DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+#
+# This code is free software; you can redistribute it and/or modify it
+# under the terms of the GNU General Public License version 2 only, as
+# published by the Free Software Foundation.  Oracle designates this
+# particular file as subject to the "Classpath" exception as provided
+# by Oracle in the LICENSE file that accompanied this code.
+#
+# This code 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
+# version 2 for more details (a copy is included in the LICENSE file that
+# accompanied this code).
+#
+# You should have received a copy of the GNU General Public License version
+# 2 along with this work; if not, write to the Free Software Foundation,
+# Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+#
+# Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
+# or visit www.oracle.com if you need additional information or have any
+# questions.
+#
+
+default: all
+
+include $(SPEC)
+include MakeBase.gmk
+
+##########################################################################################
+
+### TZDB tool needs files from java.time.zone package
+
+define tzdb_copyfiles
+	$(call MakeTargetDir)
+	$(RM) '$@'
+	$(SED) -e "s/package java.time.zone/package build.tools.tzdb/" \
+        < $(<) > $@
+endef
+
+$(eval $(call SetupCopyFiles,COPY_INTERIM_TZDB, \
+    SRC := $(TOPDIR)/src/java.base/share/classes/java/time/zone, \
+    DEST := $(BUILDTOOLS_OUTPUTDIR)/interim_tzdb_classes/build/tools/tzdb, \
+    FILES := ZoneRules.java ZoneOffsetTransition.java ZoneOffsetTransitionRule.java Ser.java, \
+    MACRO := tzdb_copyfiles))
+
+##########################################################################################
+
+all: $(COPY_INTERIM_TZDB)
--- a/make/Main.gmk	Fri Aug 23 14:25:20 2019 +0100
+++ b/make/Main.gmk	Mon Aug 26 11:20:26 2019 +0530
@@ -77,6 +77,10 @@

 interim-cldrconverter:
 	+($(CD) $(TOPDIR)/make && $(MAKE) $(MAKE_ARGS) -f CopyInterimCLDRConverter.gmk)
+
+interim-tzdb:
+	+($(CD) $(TOPDIR)/make && $(MAKE) $(MAKE_ARGS) -f CopyInterimTZDB.gmk)
+

 buildtools-jdk:
 	+($(CD) $(TOPDIR)/make && $(MAKE) $(MAKE_ARGS) -f CompileToolsJdk.gmk)
@@ -88,7 +92,7 @@
 	+($(CD) $(TOPDIR)/make && $(MAKE) $(MAKE_ARGS) -f CompileToolsHotspot.gmk)

 ALL_TARGETS += buildtools-langtools interim-langtools \
-    interim-rmic interim-cldrconverter buildtools-jdk buildtools-modules \
+    interim-rmic interim-cldrconverter interim-tzdb buildtools-jdk buildtools-modules \
     buildtools-hotspot

 ################################################################################
@@ -648,7 +652,7 @@

   interim-langtools: $(INTERIM_LANGTOOLS_GENSRC_TARGETS)

-  buildtools-jdk: interim-langtools interim-cldrconverter
+  buildtools-jdk: interim-langtools interim-cldrconverter interim-tzdb

   buildtools-hotspot: interim-langtools
--- a/make/RunTests.gmk	Fri Aug 23 14:25:20 2019 +0100
+++ b/make/RunTests.gmk	Mon Aug 26 11:20:26 2019 +0530
@@ -185,12 +185,13 @@
 	)
 	$$(call ExecuteWithLog, $$@.check, \
 	    $$(FIXPATH) $$(JDK_UNDER_TEST)/bin/java \
-	        $$($1_VM_OPTIONS) -XX:+UnlockDiagnosticVMOptions \
+	        $$($1_VM_OPTIONS) -XX:+UnlockDiagnosticVMOptions -XX:+UnlockExperimentalVMOptions \
 	        -XX:+PrintAOT -XX:+UseAOTStrictLoading \
 	        -XX:AOTLibrary=$$@ -version \
 	         > $$@.verify-aot \
 	)

+  $1_AOT_OPTIONS += -XX:+UnlockExperimentalVMOptions
   $1_AOT_OPTIONS += -XX:AOTLibrary=$$($1_AOT_LIB)
   $1_AOT_TARGETS += $$($1_AOT_LIB)
 endef
--- a/make/common/Modules.gmk	Fri Aug 23 14:25:20 2019 +0100
+++ b/make/common/Modules.gmk	Mon Aug 26 11:20:26 2019 +0530
@@ -1,5 +1,5 @@
 #
-# Copyright (c) 2014, 2018, Oracle and/or its affiliates. All rights reserved.
+# Copyright (c) 2014, 2019, Oracle and/or its affiliates. All rights reserved.
 # DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
 #
 # This code is free software; you can redistribute it and/or modify it
@@ -64,6 +64,7 @@
     jdk.management.jfr \
     jdk.management.agent \
     jdk.net \
+    jdk.nio.mapmode \
     jdk.sctp \
     jdk.unsupported \
     #
--- a/make/common/ZipArchive.gmk	Fri Aug 23 14:25:20 2019 +0100
+++ b/make/common/ZipArchive.gmk	Mon Aug 26 11:20:26 2019 +0530
@@ -54,14 +54,17 @@
 SetupZipArchive = $(NamedParamsMacroTemplate)
 define SetupZipArchiveBody

+  # Create a version $1_SRC with a guaranteed trailing slash
+  $1_SRC_SLASH := $$(addsuffix /, $$(patsubst %/, %, $$($1_SRC)))
+
   # To avoid running find over too large sets of files, which causes make to crash
   # on some configurations (cygwin), use INCLUDES and INCLUDE_FILES to build a set
   # of directories to run find in, if available.
   ifneq ($$($1_INCLUDES)$$($1_INCLUDE_FILES),)
-    $1_FIND_LIST := $$(wildcard $$(foreach i,$$($1_SRC), \
-        $$(addprefix $$i/,$$($1_INCLUDES) $$($1_INCLUDE_FILES))))
+    $1_FIND_LIST := $$(wildcard $$(foreach s,$$($1_SRC_SLASH), \
+        $$(addprefix $$s,$$($1_INCLUDES) $$($1_INCLUDE_FILES))))
   else
-    $1_FIND_LIST := $$($1_SRC)
+    $1_FIND_LIST := $$($1_SRC_SLASH)
   endif

   # Find all files in the source tree.
@@ -96,15 +99,15 @@
   endif
   ifneq ($$($1_EXCLUDES),)
     $1_ZIP_EXCLUDES := $$(addprefix -x$(SPACE)$(DQUOTE),$$(addsuffix /*$(DQUOTE),$$($1_EXCLUDES)))
-    $1_SRC_EXCLUDES := $$(foreach i,$$($1_SRC),$$(addprefix $$i/,$$(addsuffix /%,$$($1_EXCLUDES))))
+    $1_SRC_EXCLUDES := $$(foreach s,$$($1_SRC_SLASH),$$(addprefix $$s,$$(addsuffix /%,$$($1_EXCLUDES))))
     $1_ALL_SRCS := $$(filter-out $$($1_SRC_EXCLUDES),$$($1_ALL_SRCS))
   endif
   ifneq ($$($1_EXCLUDE_FILES),)
     $1_SRC_EXCLUDE_FILES := $$(addprefix %, $$($1_EXCLUDE_FILES)) $$($1_EXCLUDE_FILES)
     $1_ALL_SRCS := $$(filter-out $$($1_SRC_EXCLUDE_FILES), $$($1_ALL_SRCS))
-    $$(foreach s, $$($1_SRC), \
+    $$(foreach s, $$($1_SRC_SLASH), \
       $$(eval $1_ZIP_EXCLUDES_$$s += \
-          $$(addprefix -x$$(SPACE), $$(patsubst $$s/%,%, $$($1_EXCLUDE_FILES))) \
+          $$(addprefix -x$$(SPACE), $$(patsubst $$s%,%, $$($1_EXCLUDE_FILES))) \
       ) \
     )
   endif
@@ -113,7 +116,7 @@
     $1_ZIP_EXCLUDES += $$(addprefix -x$(SPACE), $$(subst %,\*,$$($1_EXCLUDE_PATTERNS)))
   endif
   # Rewrite src dir specific exclude patterns to zip excludes
-  $$(foreach s, $$($1_SRC), \
+  $$(foreach s, $$($1_SRC_SLASH), \
     $$(if $$($1_EXCLUDE_PATTERNS_$$s), \
       $$(eval $1_ZIP_EXCLUDES_$$s += \
           $$(addprefix -x$$(SPACE), $$(subst %,\*,$$($1_EXCLUDE_PATTERNS_$$s))) \
@@ -134,7 +137,26 @@
   $$($1_ZIP) : $$($1_ALL_SRCS) $$($1_EXTRA_DEPS)
 	$$(call LogWarn, Updating $$($1_NAME))
 	$$(call MakeTargetDir)
-	$$(foreach s,$$($1_SRC), $$(call ExecuteWithLog, \
+        # Find duplicate file names in the SRC and generate excludes for all
+        # instances that should not be included. Run this rather expensive
+        # calculation as part of the recipe to avoid running it when nothing
+        # needs to be rebuilt. The drawback is that we cannot exclude these
+        # files from the make prerequisites list, but the number of files is
+        # usually small so a very rare unnecessary rebuild is worth it.
+        # (The inner most foreach here is used instead of eval to declare a
+        # local variable.)
+	$$(foreach root, $$($1_SRC_SLASH), \
+	  $$(foreach file, $$(filter $$(root)%, $$($1_ALL_SRCS)), \
+	    $$(foreach relfile, $$(patsubst $$(root)%, %, $$(file)), \
+	      $$(if $$($1_relfiles_$$(call DoubleDollar, $$(relfile))), \
+	        $$(eval $1_ZIP_EXCLUDES_$$(root) += -x $$(relfile)) \
+	      , \
+	        $$(eval $1_relfiles_$$(call DoubleDollar, $$(relfile)) := 1) \
+	      ) \
+	    ) \
+	  ) \
+	)
+	$$(foreach s,$$($1_SRC_SLASH), $$(call ExecuteWithLog, \
 	    $$(SUPPORT_OUTPUTDIR)/zip/$$(patsubst $$(OUTPUTDIR)/%,%, $$@), \
 	    (cd $$s && $(ZIPEXE) -qru $$($1_ZIP_OPTIONS) $$@ . \
 	        $$($1_ZIP_INCLUDES) $$($1_ZIP_EXCLUDES) -x \*_the.\* \
--- a/make/data/tzdata/VERSION	Fri Aug 23 14:25:20 2019 +0100
+++ b/make/data/tzdata/VERSION	Mon Aug 26 11:20:26 2019 +0530
@@ -21,4 +21,4 @@
 # or visit www.oracle.com if you need additional information or have any
 # questions.
 #
-tzdata2019a
+tzdata2019b
--- a/make/data/tzdata/africa	Fri Aug 23 14:25:20 2019 +0100
+++ b/make/data/tzdata/africa	Mon Aug 26 11:20:26 2019 +0530
@@ -112,7 +112,7 @@
 Rule	Algeria	1980	only	-	Oct	31	 2:00	0	-
 # Shanks & Pottenger give 0:09:20 for Paris Mean Time; go with Howse's
 # more precise 0:09:21.
-# Zone	NAME		GMTOFF	RULES	FORMAT	[UNTIL]
+# Zone	NAME		STDOFF	RULES	FORMAT	[UNTIL]
 Zone	Africa/Algiers	0:12:12 -	LMT	1891 Mar 15  0:01
 			0:09:21	-	PMT	1911 Mar 11 # Paris Mean Time
 			0:00	Algeria	WE%sT	1940 Feb 25  2:00
@@ -147,7 +147,7 @@
 # For now, ignore that and follow the 1911-05-26 Portuguese decree
 # (see Europe/Lisbon).
 #
-# Zone	NAME		GMTOFF	RULES	FORMAT	[UNTIL]
+# Zone	NAME		STDOFF	RULES	FORMAT	[UNTIL]
 Zone Atlantic/Cape_Verde -1:34:04 -	LMT	1912 Jan 01  2:00u # Praia
 			-2:00	-	-02	1942 Sep
 			-2:00	1:00	-01	1945 Oct 15
@@ -158,7 +158,7 @@
 # See Africa/Lagos.

 # Chad
-# Zone	NAME		GMTOFF	RULES	FORMAT	[UNTIL]
+# Zone	NAME		STDOFF	RULES	FORMAT	[UNTIL]
 Zone	Africa/Ndjamena	1:00:12 -	LMT	1912        # N'Djamena
 			1:00	-	WAT	1979 Oct 14
 			1:00	1:00	WAST	1980 Mar  8
@@ -174,7 +174,7 @@
 # See Africa/Lagos.

 # Côte d'Ivoire / Ivory Coast
-# Zone	NAME		GMTOFF	RULES	FORMAT	[UNTIL]
+# Zone	NAME		STDOFF	RULES	FORMAT	[UNTIL]
 Zone	Africa/Abidjan	-0:16:08 -	LMT	1912
 			 0:00	-	GMT
 Link Africa/Abidjan Africa/Bamako	# Mali
@@ -379,7 +379,7 @@
 Rule	Egypt	2014	only	-	Jul	31	24:00	1:00	S
 Rule	Egypt	2014	only	-	Sep	lastThu	24:00	0	-

-# Zone	NAME		GMTOFF	RULES	FORMAT	[UNTIL]
+# Zone	NAME		STDOFF	RULES	FORMAT	[UNTIL]
 Zone	Africa/Cairo	2:05:09 -	LMT	1900 Oct
 			2:00	Egypt	EE%sT

@@ -437,7 +437,7 @@
 # Rule	NAME	FROM	TO	TYPE	IN	ON	AT	SAVE	LETTER/S
 Rule	Ghana	1920	1942	-	Sep	 1	0:00	0:20	-
 Rule	Ghana	1920	1942	-	Dec	31	0:00	0	-
-# Zone	NAME		GMTOFF	RULES	FORMAT	[UNTIL]
+# Zone	NAME		STDOFF	RULES	FORMAT	[UNTIL]
 Zone	Africa/Accra	-0:00:52 -	LMT	1918
 			 0:00	Ghana	GMT/+0020

@@ -451,13 +451,13 @@
 # evidently confusing the date of the Portuguese decree
 # (see Europe/Lisbon) with the date that it took effect.
 #
-# Zone	NAME		GMTOFF	RULES	FORMAT	[UNTIL]
+# Zone	NAME		STDOFF	RULES	FORMAT	[UNTIL]
 Zone	Africa/Bissau	-1:02:20 -	LMT	1912 Jan  1  1:00u
 			-1:00	-	-01	1975
 			 0:00	-	GMT

 # Kenya
-# Zone	NAME		GMTOFF	RULES	FORMAT	[UNTIL]
+# Zone	NAME		STDOFF	RULES	FORMAT	[UNTIL]
 Zone	Africa/Nairobi	2:27:16	-	LMT	1928 Jul
 			3:00	-	EAT	1930
 			2:30	-	+0230	1940
@@ -492,7 +492,7 @@
 # Use the abbreviation "MMT" before 1972, as the more-accurate numeric
 # abbreviation "-004430" would be one byte over the POSIX limit.
 #
-# Zone	NAME		GMTOFF	RULES	FORMAT	[UNTIL]
+# Zone	NAME		STDOFF	RULES	FORMAT	[UNTIL]
 Zone	Africa/Monrovia	-0:43:08 -	LMT	1882
 			-0:43:08 -	MMT	1919 Mar # Monrovia Mean Time
 			-0:44:30 -	MMT	1972 Jan 7 # approximately MMT
@@ -542,7 +542,7 @@
 Rule	Libya	1997	only	-	Oct	 4	0:00	0	-
 Rule	Libya	2013	only	-	Mar	lastFri	1:00	1:00	S
 Rule	Libya	2013	only	-	Oct	lastFri	2:00	0	-
-# Zone	NAME		GMTOFF	RULES	FORMAT	[UNTIL]
+# Zone	NAME		STDOFF	RULES	FORMAT	[UNTIL]
 Zone	Africa/Tripoli	0:52:44 -	LMT	1920
 			1:00	Libya	CE%sT	1959
 			2:00	-	EET	1982
@@ -652,7 +652,7 @@
 Rule Mauritius	1983	only	-	Mar	21	0:00	0	-
 Rule Mauritius	2008	only	-	Oct	lastSun	2:00	1:00	-
 Rule Mauritius	2009	only	-	Mar	lastSun	2:00	0	-
-# Zone	NAME		GMTOFF	RULES	FORMAT	[UNTIL]
+# Zone	NAME		STDOFF	RULES	FORMAT	[UNTIL]
 Zone Indian/Mauritius	3:50:00 -	LMT	1907 # Port Louis
 			4:00 Mauritius	+04/+05
 # Agalega Is, Rodriguez
@@ -883,18 +883,24 @@
 # the week end after....  The government does not announce yet the decision
 # about this temporary change.  But it s 99% sure that it will be the case,
 # as in previous years.  An unofficial survey was done these days, showing
-# that 64% of asked peopke are ok for moving from +1 to +0 during Ramadan.
+# that 64% of asked people are ok for moving from +1 to +0 during Ramadan.
 # https://leconomiste.com/article/1035870-enquete-l-economiste-sunergia-64-des-marocains-plebiscitent-le-gmt-pendant-ramadan
+
+# From Naoufal Semlali (2019-04-16):
+# Morocco will be on GMT starting from Sunday, May 5th 2019 at 3am.
+# The switch to GMT+1 will occur on Sunday, June 9th 2019 at 2am....
+# http://fr.le360.ma/societe/voici-la-date-du-retour-a-lheure-legale-au-maroc-188222
 #
-# From Paul Eggert (2018-11-01):
-# For now, guess that Morocco will fall back at 03:00 the last Sunday
-# before Ramadan, and spring forward at 02:00 the first Sunday after
+# From Paul Eggert (2019-05-20):
+# This agrees with our 2018-11-01 guess that the Moroccan government
+# would continue the practice of falling back at 03:00 the last Sunday
+# before Ramadan, and of springing forward at 02:00 the first Sunday after
 # Ramadan, as this has been the practice since 2012.  To implement this,
-# transition dates for 2019 through 2037 were determined by running the
-# following program under GNU Emacs 26.1.
+# transition dates for 2019 through 2087 were determined by running the
+# following program under GNU Emacs 26.2.
 # (let ((islamic-year 1440))
 #   (require 'cal-islam)
-#   (while (< islamic-year 1460)
+#   (while (< islamic-year 1511)
 #     (let ((a (calendar-islamic-to-absolute (list 9 1 islamic-year)))
 #           (b (calendar-islamic-to-absolute (list 10 1 islamic-year)))
 #           (sunday 0))
@@ -941,7 +947,7 @@
 Rule	Morocco	2012	only	-	Sep	30	 3:00	0	-
 Rule	Morocco	2013	only	-	Jul	 7	 3:00	0	-
 Rule	Morocco	2013	only	-	Aug	10	 2:00	1:00	-
-Rule	Morocco	2013	2017	-	Oct	lastSun	 3:00	0	-
+Rule	Morocco	2013	2018	-	Oct	lastSun	 3:00	0	-
 Rule	Morocco	2014	2018	-	Mar	lastSun	 2:00	1:00	-
 Rule	Morocco	2014	only	-	Jun	28	 3:00	0	-
 Rule	Morocco	2014	only	-	Aug	 2	 2:00	1:00	-
@@ -953,53 +959,159 @@
 Rule	Morocco	2017	only	-	Jul	 2	 2:00	1:00	-
 Rule	Morocco	2018	only	-	May	13	 3:00	0	-
 Rule	Morocco	2018	only	-	Jun	17	 2:00	1:00	-
-Rule	Morocco	2019	only	-	May	 5	 3:00	0	-
-Rule	Morocco	2019	only	-	Jun	 9	 2:00	1:00	-
-Rule	Morocco	2020	only	-	Apr	19	 3:00	0	-
-Rule	Morocco	2020	only	-	May	24	 2:00	1:00	-
-Rule	Morocco	2021	only	-	Apr	11	 3:00	0	-
-Rule	Morocco	2021	only	-	May	16	 2:00	1:00	-
-Rule	Morocco	2022	only	-	Mar	27	 3:00	0	-
-Rule	Morocco	2022	only	-	May	 8	 2:00	1:00	-
-Rule	Morocco	2023	only	-	Mar	19	 3:00	0	-
-Rule	Morocco	2023	only	-	Apr	23	 2:00	1:00	-
-Rule	Morocco	2024	only	-	Mar	10	 3:00	0	-
-Rule	Morocco	2024	only	-	Apr	14	 2:00	1:00	-
-Rule	Morocco	2025	only	-	Feb	23	 3:00	0	-
-Rule	Morocco	2025	only	-	Apr	 6	 2:00	1:00	-
-Rule	Morocco	2026	only	-	Feb	15	 3:00	0	-
-Rule	Morocco	2026	only	-	Mar	22	 2:00	1:00	-
-Rule	Morocco	2027	only	-	Feb	 7	 3:00	0	-
-Rule	Morocco	2027	only	-	Mar	14	 2:00	1:00	-
-Rule	Morocco	2028	only	-	Jan	23	 3:00	0	-
-Rule	Morocco	2028	only	-	Feb	27	 2:00	1:00	-
-Rule	Morocco	2029	only	-	Jan	14	 3:00	0	-
-Rule	Morocco	2029	only	-	Feb	18	 2:00	1:00	-
-Rule	Morocco	2029	only	-	Dec	30	 3:00	0	-
-Rule	Morocco	2030	only	-	Feb	10	 2:00	1:00	-
-Rule	Morocco	2030	only	-	Dec	22	 3:00	0	-
-Rule	Morocco	2031	only	-	Jan	26	 2:00	1:00	-
-Rule	Morocco	2031	only	-	Dec	14	 3:00	0	-
-Rule	Morocco	2032	only	-	Jan	18	 2:00	1:00	-
-Rule	Morocco	2032	only	-	Nov	28	 3:00	0	-
-Rule	Morocco	2033	only	-	Jan	 9	 2:00	1:00	-
-Rule	Morocco	2033	only	-	Nov	20	 3:00	0	-
-Rule	Morocco	2033	only	-	Dec	25	 2:00	1:00	-
-Rule	Morocco	2034	only	-	Nov	 5	 3:00	0	-
-Rule	Morocco	2034	only	-	Dec	17	 2:00	1:00	-
-Rule	Morocco	2035	only	-	Oct	28	 3:00	0	-
-Rule	Morocco	2035	only	-	Dec	 2	 2:00	1:00	-
-Rule	Morocco	2036	only	-	Oct	19	 3:00	0	-
-Rule	Morocco	2036	only	-	Nov	23	 2:00	1:00	-
-Rule	Morocco	2037	only	-	Oct	 4	 3:00	0	-
-Rule	Morocco	2037	only	-	Nov	15	 2:00	1:00	-
+Rule	Morocco	2019	only	-	May	 5	 3:00	-1:00	-
+Rule	Morocco	2019	only	-	Jun	 9	 2:00	0	-
+Rule	Morocco	2020	only	-	Apr	19	 3:00	-1:00	-
+Rule	Morocco	2020	only	-	May	24	 2:00	0	-
+Rule	Morocco	2021	only	-	Apr	11	 3:00	-1:00	-
+Rule	Morocco	2021	only	-	May	16	 2:00	0	-
+Rule	Morocco	2022	only	-	Mar	27	 3:00	-1:00	-
+Rule	Morocco	2022	only	-	May	 8	 2:00	0	-
+Rule	Morocco	2023	only	-	Mar	19	 3:00	-1:00	-
+Rule	Morocco	2023	only	-	Apr	23	 2:00	0	-
+Rule	Morocco	2024	only	-	Mar	10	 3:00	-1:00	-
+Rule	Morocco	2024	only	-	Apr	14	 2:00	0	-
+Rule	Morocco	2025	only	-	Feb	23	 3:00	-1:00	-
+Rule	Morocco	2025	only	-	Apr	 6	 2:00	0	-
+Rule	Morocco	2026	only	-	Feb	15	 3:00	-1:00	-
+Rule	Morocco	2026	only	-	Mar	22	 2:00	0	-
+Rule	Morocco	2027	only	-	Feb	 7	 3:00	-1:00	-
+Rule	Morocco	2027	only	-	Mar	14	 2:00	0	-
+Rule	Morocco	2028	only	-	Jan	23	 3:00	-1:00	-
+Rule	Morocco	2028	only	-	Feb	27	 2:00	0	-
+Rule	Morocco	2029	only	-	Jan	14	 3:00	-1:00	-
+Rule	Morocco	2029	only	-	Feb	18	 2:00	0	-
+Rule	Morocco	2029	only	-	Dec	30	 3:00	-1:00	-
+Rule	Morocco	2030	only	-	Feb	10	 2:00	0	-
+Rule	Morocco	2030	only	-	Dec	22	 3:00	-1:00	-
+Rule	Morocco	2031	only	-	Jan	26	 2:00	0	-
+Rule	Morocco	2031	only	-	Dec	14	 3:00	-1:00	-
+Rule	Morocco	2032	only	-	Jan	18	 2:00	0	-
+Rule	Morocco	2032	only	-	Nov	28	 3:00	-1:00	-
+Rule	Morocco	2033	only	-	Jan	 9	 2:00	0	-
+Rule	Morocco	2033	only	-	Nov	20	 3:00	-1:00	-
+Rule	Morocco	2033	only	-	Dec	25	 2:00	0	-
+Rule	Morocco	2034	only	-	Nov	 5	 3:00	-1:00	-
+Rule	Morocco	2034	only	-	Dec	17	 2:00	0	-
+Rule	Morocco	2035	only	-	Oct	28	 3:00	-1:00	-
+Rule	Morocco	2035	only	-	Dec	 2	 2:00	0	-
+Rule	Morocco	2036	only	-	Oct	19	 3:00	-1:00	-
+Rule	Morocco	2036	only	-	Nov	23	 2:00	0	-
+Rule	Morocco	2037	only	-	Oct	 4	 3:00	-1:00	-
+Rule	Morocco	2037	only	-	Nov	15	 2:00	0	-
+Rule	Morocco	2038	only	-	Sep	26	 3:00	-1:00	-
+Rule	Morocco	2038	only	-	Oct	31	 2:00	0	-
+Rule	Morocco	2039	only	-	Sep	18	 3:00	-1:00	-
+Rule	Morocco	2039	only	-	Oct	23	 2:00	0	-
+Rule	Morocco	2040	only	-	Sep	 2	 3:00	-1:00	-
+Rule	Morocco	2040	only	-	Oct	14	 2:00	0	-
+Rule	Morocco	2041	only	-	Aug	25	 3:00	-1:00	-
+Rule	Morocco	2041	only	-	Sep	29	 2:00	0	-
+Rule	Morocco	2042	only	-	Aug	10	 3:00	-1:00	-
+Rule	Morocco	2042	only	-	Sep	21	 2:00	0	-
+Rule	Morocco	2043	only	-	Aug	 2	 3:00	-1:00	-
+Rule	Morocco	2043	only	-	Sep	 6	 2:00	0	-
+Rule	Morocco	2044	only	-	Jul	24	 3:00	-1:00	-
+Rule	Morocco	2044	only	-	Aug	28	 2:00	0	-
+Rule	Morocco	2045	only	-	Jul	 9	 3:00	-1:00	-
+Rule	Morocco	2045	only	-	Aug	20	 2:00	0	-
+Rule	Morocco	2046	only	-	Jul	 1	 3:00	-1:00	-
+Rule	Morocco	2046	only	-	Aug	 5	 2:00	0	-
+Rule	Morocco	2047	only	-	Jun	23	 3:00	-1:00	-
+Rule	Morocco	2047	only	-	Jul	28	 2:00	0	-
+Rule	Morocco	2048	only	-	Jun	 7	 3:00	-1:00	-
+Rule	Morocco	2048	only	-	Jul	19	 2:00	0	-
+Rule	Morocco	2049	only	-	May	30	 3:00	-1:00	-
+Rule	Morocco	2049	only	-	Jul	 4	 2:00	0	-
+Rule	Morocco	2050	only	-	May	15	 3:00	-1:00	-
+Rule	Morocco	2050	only	-	Jun	26	 2:00	0	-
+Rule	Morocco	2051	only	-	May	 7	 3:00	-1:00	-
+Rule	Morocco	2051	only	-	Jun	11	 2:00	0	-
+Rule	Morocco	2052	only	-	Apr	28	 3:00	-1:00	-
+Rule	Morocco	2052	only	-	Jun	 2	 2:00	0	-
+Rule	Morocco	2053	only	-	Apr	13	 3:00	-1:00	-
+Rule	Morocco	2053	only	-	May	25	 2:00	0	-
+Rule	Morocco	2054	only	-	Apr	 5	 3:00	-1:00	-
+Rule	Morocco	2054	only	-	May	10	 2:00	0	-
+Rule	Morocco	2055	only	-	Mar	28	 3:00	-1:00	-
+Rule	Morocco	2055	only	-	May	 2	 2:00	0	-
+Rule	Morocco	2056	only	-	Mar	12	 3:00	-1:00	-
+Rule	Morocco	2056	only	-	Apr	23	 2:00	0	-
+Rule	Morocco	2057	only	-	Mar	 4	 3:00	-1:00	-
+Rule	Morocco	2057	only	-	Apr	 8	 2:00	0	-
+Rule	Morocco	2058	only	-	Feb	17	 3:00	-1:00	-
+Rule	Morocco	2058	only	-	Mar	31	 2:00	0	-
+Rule	Morocco	2059	only	-	Feb	 9	 3:00	-1:00	-
+Rule	Morocco	2059	only	-	Mar	16	 2:00	0	-
+Rule	Morocco	2060	only	-	Feb	 1	 3:00	-1:00	-
+Rule	Morocco	2060	only	-	Mar	 7	 2:00	0	-
+Rule	Morocco	2061	only	-	Jan	16	 3:00	-1:00	-
+Rule	Morocco	2061	only	-	Feb	27	 2:00	0	-
+Rule	Morocco	2062	only	-	Jan	 8	 3:00	-1:00	-
+Rule	Morocco	2062	only	-	Feb	12	 2:00	0	-
+Rule	Morocco	2062	only	-	Dec	31	 3:00	-1:00	-
+Rule	Morocco	2063	only	-	Feb	 4	 2:00	0	-
+Rule	Morocco	2063	only	-	Dec	16	 3:00	-1:00	-
+Rule	Morocco	2064	only	-	Jan	20	 2:00	0	-
+Rule	Morocco	2064	only	-	Dec	 7	 3:00	-1:00	-
+Rule	Morocco	2065	only	-	Jan	11	 2:00	0	-
+Rule	Morocco	2065	only	-	Nov	22	 3:00	-1:00	-
+Rule	Morocco	2066	only	-	Jan	 3	 2:00	0	-
+Rule	Morocco	2066	only	-	Nov	14	 3:00	-1:00	-
+Rule	Morocco	2066	only	-	Dec	19	 2:00	0	-
+Rule	Morocco	2067	only	-	Nov	 6	 3:00	-1:00	-
+Rule	Morocco	2067	only	-	Dec	11	 2:00	0	-
+Rule	Morocco	2068	only	-	Oct	21	 3:00	-1:00	-
+Rule	Morocco	2068	only	-	Dec	 2	 2:00	0	-
+Rule	Morocco	2069	only	-	Oct	13	 3:00	-1:00	-
+Rule	Morocco	2069	only	-	Nov	17	 2:00	0	-
+Rule	Morocco	2070	only	-	Oct	 5	 3:00	-1:00	-
+Rule	Morocco	2070	only	-	Nov	 9	 2:00	0	-
+Rule	Morocco	2071	only	-	Sep	20	 3:00	-1:00	-
+Rule	Morocco	2071	only	-	Oct	25	 2:00	0	-
+Rule	Morocco	2072	only	-	Sep	11	 3:00	-1:00	-
+Rule	Morocco	2072	only	-	Oct	16	 2:00	0	-
+Rule	Morocco	2073	only	-	Aug	27	 3:00	-1:00	-
+Rule	Morocco	2073	only	-	Oct	 8	 2:00	0	-
+Rule	Morocco	2074	only	-	Aug	19	 3:00	-1:00	-
+Rule	Morocco	2074	only	-	Sep	23	 2:00	0	-
+Rule	Morocco	2075	only	-	Aug	11	 3:00	-1:00	-
+Rule	Morocco	2075	only	-	Sep	15	 2:00	0	-
+Rule	Morocco	2076	only	-	Jul	26	 3:00	-1:00	-
+Rule	Morocco	2076	only	-	Sep	 6	 2:00	0	-
+Rule	Morocco	2077	only	-	Jul	18	 3:00	-1:00	-
+Rule	Morocco	2077	only	-	Aug	22	 2:00	0	-
+Rule	Morocco	2078	only	-	Jul	10	 3:00	-1:00	-
+Rule	Morocco	2078	only	-	Aug	14	 2:00	0	-
+Rule	Morocco	2079	only	-	Jun	25	 3:00	-1:00	-
+Rule	Morocco	2079	only	-	Jul	30	 2:00	0	-
+Rule	Morocco	2080	only	-	Jun	16	 3:00	-1:00	-
+Rule	Morocco	2080	only	-	Jul	21	 2:00	0	-
+Rule	Morocco	2081	only	-	Jun	 1	 3:00	-1:00	-
+Rule	Morocco	2081	only	-	Jul	13	 2:00	0	-
+Rule	Morocco	2082	only	-	May	24	 3:00	-1:00	-
+Rule	Morocco	2082	only	-	Jun	28	 2:00	0	-
+Rule	Morocco	2083	only	-	May	16	 3:00	-1:00	-
+Rule	Morocco	2083	only	-	Jun	20	 2:00	0	-
+Rule	Morocco	2084	only	-	Apr	30	 3:00	-1:00	-
+Rule	Morocco	2084	only	-	Jun	11	 2:00	0	-
+Rule	Morocco	2085	only	-	Apr	22	 3:00	-1:00	-
+Rule	Morocco	2085	only	-	May	27	 2:00	0	-
+Rule	Morocco	2086	only	-	Apr	14	 3:00	-1:00	-
+Rule	Morocco	2086	only	-	May	19	 2:00	0	-
+Rule	Morocco	2087	only	-	Mar	30	 3:00	-1:00	-
+Rule	Morocco	2087	only	-	May	 4	 2:00	0	-
+# For dates after the somewhat-arbitrary cutoff of 2087, assume that
+# Morocco will no longer observe DST.  At some point this table will
+# need to be extended, though quite possibly Morocco will change the
+# rules first.

-# Zone	NAME		GMTOFF	RULES	FORMAT	[UNTIL]
+# Zone	NAME		STDOFF	RULES	FORMAT	[UNTIL]
 Zone Africa/Casablanca	-0:30:20 -	LMT	1913 Oct 26
 			 0:00	Morocco	+00/+01	1984 Mar 16
 			 1:00	-	+01	1986
 			 0:00	Morocco	+00/+01	2018 Oct 28  3:00
-			 0:00	Morocco	+00/+01
+			 1:00	Morocco	+01/+00

 # Western Sahara
 #
@@ -1015,7 +1127,7 @@
 Zone Africa/El_Aaiun	-0:52:48 -	LMT	1934 Jan # El Aaiún
 			-1:00	-	-01	1976 Apr 14
 			 0:00	Morocco	+00/+01	2018 Oct 28  3:00
-			 0:00	Morocco	+00/+01
+			 1:00	Morocco	+01/+00

 # Mozambique
 #
@@ -1024,7 +1136,7 @@
 # https://dre.pt/pdf1sdip/1911/05/12500/23132313.pdf
 # merely made it official?
 #
-# Zone	NAME		GMTOFF	RULES	FORMAT	[UNTIL]
+# Zone	NAME		STDOFF	RULES	FORMAT	[UNTIL]
 Zone	Africa/Maputo	2:10:20 -	LMT	1903 Mar
 			2:00	-	CAT
 Link Africa/Maputo Africa/Blantyre	# Malawi
@@ -1087,37 +1199,37 @@

 # RULE	NAME	FROM	TO	TYPE	IN	ON	AT	SAVE	LETTER/S
 # Vanguard section, for zic and other parsers that support negative DST.
-#Rule	Namibia	1994	only	-	Mar	21	0:00	-1:00	WAT
-#Rule	Namibia	1994	2017	-	Sep	Sun>=1	2:00	0	CAT
-#Rule	Namibia	1995	2017	-	Apr	Sun>=1	2:00	-1:00	WAT
+Rule	Namibia	1994	only	-	Mar	21	0:00	-1:00	WAT
+Rule	Namibia	1994	2017	-	Sep	Sun>=1	2:00	0	CAT
+Rule	Namibia	1995	2017	-	Apr	Sun>=1	2:00	-1:00	WAT
 # Rearguard section, for parsers that do not support negative DST.
-Rule	Namibia	1994	only	-	Mar	21	0:00	0	WAT
-Rule	Namibia	1994	2017	-	Sep	Sun>=1	2:00	1:00	CAT
-Rule	Namibia	1995	2017	-	Apr	Sun>=1	2:00	0	WAT
+#Rule	Namibia	1994	only	-	Mar	21	0:00	0	WAT
+#Rule	Namibia	1994	2017	-	Sep	Sun>=1	2:00	1:00	CAT
+#Rule	Namibia	1995	2017	-	Apr	Sun>=1	2:00	0	WAT
 # End of rearguard section.

-# Zone	NAME		GMTOFF	RULES	FORMAT	[UNTIL]
+# Zone	NAME		STDOFF	RULES	FORMAT	[UNTIL]
 Zone	Africa/Windhoek	1:08:24 -	LMT	1892 Feb 8
 			1:30	-	+0130	1903 Mar
 			2:00	-	SAST	1942 Sep 20  2:00
 			2:00	1:00	SAST	1943 Mar 21  2:00
 			2:00	-	SAST	1990 Mar 21 # independence
 # Vanguard section, for zic and other parsers that support negative DST.
-#			2:00	Namibia	%s
+			2:00	Namibia	%s
 # Rearguard section, for parsers that do not support negative DST.
-			2:00	-	CAT	1994 Mar 21  0:00
+#			2:00	-	CAT	1994 Mar 21  0:00
 # From Paul Eggert (2017-04-07):
 # The official date of the 2017 rule change was 2017-10-24.  See:
 # http://www.lac.org.na/laws/annoSTAT/Namibian%20Time%20Act%209%20of%202017.pdf
-			1:00	Namibia	%s	2017 Oct 24
-			2:00	-	CAT
+#			1:00	Namibia	%s	2017 Oct 24
+#			2:00	-	CAT
 # End of rearguard section.

 # Niger
 # See Africa/Lagos.

 # Nigeria
-# Zone	NAME		GMTOFF	RULES	FORMAT	[UNTIL]
+# Zone	NAME		STDOFF	RULES	FORMAT	[UNTIL]
 Zone	Africa/Lagos	0:13:36 -	LMT	1919 Sep
 			1:00	-	WAT
 Link Africa/Lagos Africa/Bangui	     # Central African Republic
@@ -1131,7 +1243,7 @@
 Link Africa/Lagos Africa/Porto-Novo  # Benin

 # Réunion
-# Zone	NAME		GMTOFF	RULES	FORMAT	[UNTIL]
+# Zone	NAME		STDOFF	RULES	FORMAT	[UNTIL]
 Zone	Indian/Reunion	3:41:52 -	LMT	1911 Jun # Saint-Denis
 			4:00	-	+04
 #
@@ -1191,7 +1303,7 @@
 # See Africa/Abidjan.

 # Seychelles
-# Zone	NAME		GMTOFF	RULES	FORMAT	[UNTIL]
+# Zone	NAME		STDOFF	RULES	FORMAT	[UNTIL]
 Zone	Indian/Mahe	3:41:48 -	LMT	1906 Jun # Victoria
 			4:00	-	+04
 # From Paul Eggert (2001-05-30):
@@ -1211,7 +1323,7 @@
 # Rule	NAME	FROM	TO	TYPE	IN	ON	AT	SAVE	LETTER/S
 Rule	SA	1942	1943	-	Sep	Sun>=15	2:00	1:00	-
 Rule	SA	1943	1944	-	Mar	Sun>=15	2:00	0	-
-# Zone	NAME		GMTOFF	RULES	FORMAT	[UNTIL]
+# Zone	NAME		STDOFF	RULES	FORMAT	[UNTIL]
 Zone Africa/Johannesburg 1:52:00 -	LMT	1892 Feb 8
 			1:30	-	SAST	1903 Mar
 			2:00	SA	SAST
@@ -1246,14 +1358,14 @@
 Rule	Sudan	1970	1985	-	Oct	15	0:00	0	-
 Rule	Sudan	1971	only	-	Apr	30	0:00	1:00	S
 Rule	Sudan	1972	1985	-	Apr	lastSun	0:00	1:00	S
-# Zone	NAME		GMTOFF	RULES	FORMAT	[UNTIL]
+# Zone	NAME		STDOFF	RULES	FORMAT	[UNTIL]
 Zone	Africa/Khartoum	2:10:08 -	LMT	1931
 			2:00	Sudan	CA%sT	2000 Jan 15 12:00
 			3:00	-	EAT	2017 Nov  1
 			2:00	-	CAT

 # South Sudan
-# Zone	NAME		GMTOFF	RULES	FORMAT	[UNTIL]
+# Zone	NAME		STDOFF	RULES	FORMAT	[UNTIL]
 Zone	Africa/Juba	2:06:28 -	LMT	1931
 			2:00	Sudan	CA%sT	2000 Jan 15 12:00
 			3:00	-	EAT
@@ -1359,7 +1471,7 @@
 # Shanks & Pottenger give 0:09:20 for Paris Mean Time; go with Howse's
 # more precise 0:09:21.
 # Shanks & Pottenger say the 1911 switch was on Mar 9; go with Howse's Mar 11.
-# Zone	NAME		GMTOFF	RULES	FORMAT	[UNTIL]
+# Zone	NAME		STDOFF	RULES	FORMAT	[UNTIL]
 Zone	Africa/Tunis	0:40:44 -	LMT	1881 May 12
 			0:09:21	-	PMT	1911 Mar 11 # Paris Mean Time
 			1:00	Tunisia	CE%sT
--- a/make/data/tzdata/antarctica	Fri Aug 23 14:25:20 2019 +0100
+++ b/make/data/tzdata/antarctica	Mon Aug 26 11:20:26 2019 +0530
@@ -36,7 +36,7 @@
 # for information.
 # Unless otherwise specified, we have no time zone information.

-# FORMAT is '-00' and GMTOFF is 0 for locations while uninhabited.
+# FORMAT is '-00' and STDOFF is 0 for locations while uninhabited.

 # Argentina - year-round bases
 # Belgrano II, Confin Coast, -770227-0343737, since 1972-02-05
@@ -93,7 +93,7 @@
 # Australian Antarctica Division informed us that Casey changed time
 # zone to UTC+11 in "the morning of 22nd October 2016".

-# Zone	NAME		GMTOFF	RULES	FORMAT	[UNTIL]
+# Zone	NAME		STDOFF	RULES	FORMAT	[UNTIL]
 Zone Antarctica/Casey	0	-	-00	1969
 			8:00	-	+08	2009 Oct 18  2:00
 			11:00	-	+11	2010 Mar  5  2:00
@@ -165,7 +165,7 @@
 # St Paul Island - near Amsterdam, uninhabited
 #	fishing stations operated variously 1819/1931
 #
-# Zone	NAME		GMTOFF	RULES	FORMAT	[UNTIL]
+# Zone	NAME		STDOFF	RULES	FORMAT	[UNTIL]
 Zone Indian/Kerguelen	0	-	-00	1950 # Port-aux-Français
 			5:00	-	+05
 #
@@ -176,7 +176,7 @@
 # Another base at Port-Martin, 50km east, began operation in 1947.
 # It was destroyed by fire on 1952-01-14.
 #
-# Zone	NAME		GMTOFF	RULES	FORMAT	[UNTIL]
+# Zone	NAME		STDOFF	RULES	FORMAT	[UNTIL]
 Zone Antarctica/DumontDUrville 0 -	-00	1947
 			10:00	-	+10	1952 Jan 14
 			0	-	-00	1956 Nov
@@ -204,7 +204,7 @@
 # Syowa station, which is the first antarctic station of Japan,
 # was established on 1957-01-29.  Since Syowa station is still the main
 # station of Japan, it's appropriate for the principal location.
-# Zone	NAME		GMTOFF	RULES	FORMAT	[UNTIL]
+# Zone	NAME		STDOFF	RULES	FORMAT	[UNTIL]
 Zone Antarctica/Syowa	0	-	-00	1957 Jan 29
 			3:00	-	+03
 # See:
@@ -254,7 +254,7 @@
 #Rule	Troll	2004	max	-	Nov	 7	1:00u	0:00	+00
 # Remove the following line when uncommenting the above '#Rule' lines.
 Rule	Troll	2004	max	-	Oct	lastSun	1:00u	0:00	+00
-# Zone	NAME		GMTOFF	RULES	FORMAT	[UNTIL]
+# Zone	NAME		STDOFF	RULES	FORMAT	[UNTIL]
 Zone Antarctica/Troll	0	-	-00	2005 Feb 12
 			0:00	Troll	%s

@@ -328,7 +328,7 @@
 # From Paul Eggert (2002-10-22)
 # <http://webexhibits.org/daylightsaving/g.html> says Rothera is -03 all year.
 #
-# Zone	NAME		GMTOFF	RULES	FORMAT	[UNTIL]
+# Zone	NAME		STDOFF	RULES	FORMAT	[UNTIL]
 Zone Antarctica/Rothera	0	-	-00	1976 Dec  1
 			-3:00	-	-03
--- a/make/data/tzdata/asia	Fri Aug 23 14:25:20 2019 +0100
+++ b/make/data/tzdata/asia	Mon Aug 26 11:20:26 2019 +0530
@@ -107,7 +107,7 @@
 Rule RussiaAsia	1996	2010	-	Oct	lastSun	 2:00s	0	-

 # Afghanistan
-# Zone	NAME		GMTOFF	RULES	FORMAT	[UNTIL]
+# Zone	NAME		STDOFF	RULES	FORMAT	[UNTIL]
 Zone	Asia/Kabul	4:36:48 -	LMT	1890
 			4:00	-	+04	1945
 			4:30	-	+0430
@@ -140,7 +140,7 @@
 # Rule	NAME	FROM	TO	TYPE	IN	ON	AT	SAVE	LETTER/S
 Rule Armenia	2011	only	-	Mar	lastSun	 2:00s	1:00	-
 Rule Armenia	2011	only	-	Oct	lastSun	 2:00s	0	-
-# Zone	NAME		GMTOFF	RULES	FORMAT	[UNTIL]
+# Zone	NAME		STDOFF	RULES	FORMAT	[UNTIL]
 Zone	Asia/Yerevan	2:58:00 -	LMT	1924 May  2
 			3:00	-	+03	1957 Mar
 			4:00 RussiaAsia +04/+05	1991 Mar 31  2:00s
@@ -166,7 +166,7 @@
 # Rule	NAME	FROM	TO	TYPE	IN	ON	AT	SAVE	LETTER/S
 Rule	Azer	1997	2015	-	Mar	lastSun	 4:00	1:00	-
 Rule	Azer	1997	2015	-	Oct	lastSun	 5:00	0	-
-# Zone	NAME		GMTOFF	RULES	FORMAT	[UNTIL]
+# Zone	NAME		STDOFF	RULES	FORMAT	[UNTIL]
 Zone	Asia/Baku	3:19:24 -	LMT	1924 May  2
 			3:00	-	+03	1957 Mar
 			4:00 RussiaAsia +04/+05	1991 Mar 31  2:00s
@@ -254,7 +254,7 @@
 Rule	Dhaka	2009	only	-	Jun	19	23:00	1:00	-
 Rule	Dhaka	2009	only	-	Dec	31	24:00	0	-

-# Zone	NAME		GMTOFF	RULES	FORMAT	[UNTIL]
+# Zone	NAME		STDOFF	RULES	FORMAT	[UNTIL]
 Zone	Asia/Dhaka	6:01:40 -	LMT	1890
 			5:53:20	-	HMT	1941 Oct    # Howrah Mean Time?
 			6:30	-	+0630	1942 May 15
@@ -264,7 +264,7 @@
 			6:00	Dhaka	+06/+07

 # Bhutan
-# Zone	NAME		GMTOFF	RULES	FORMAT	[UNTIL]
+# Zone	NAME		STDOFF	RULES	FORMAT	[UNTIL]
 Zone	Asia/Thimphu	5:58:36 -	LMT	1947 Aug 15 # or Thimbu
 			5:30	-	+0530	1987 Oct
 			6:00	-	+06
@@ -275,13 +275,13 @@
 # We have no information as to when standard time was introduced;
 # assume it occurred in 1907, the same year as Mauritius (which
 # then contained the Chagos Archipelago).
-# Zone	NAME		GMTOFF	RULES	FORMAT	[UNTIL]
+# Zone	NAME		STDOFF	RULES	FORMAT	[UNTIL]
 Zone	Indian/Chagos	4:49:40	-	LMT	1907
 			5:00	-	+05	1996
 			6:00	-	+06

 # Brunei
-# Zone	NAME		GMTOFF	RULES	FORMAT	[UNTIL]
+# Zone	NAME		STDOFF	RULES	FORMAT	[UNTIL]
 Zone	Asia/Brunei	7:39:40 -	LMT	1926 Mar # Bandar Seri Begawan
 			7:30	-	+0730	1933
 			8:00	-	+08
@@ -296,7 +296,7 @@
 # of Greenwich."  This refers to the period before Burma's transition to +0630,
 # a transition for which Shanks is the only source.

-# Zone	NAME		GMTOFF	RULES	FORMAT	[UNTIL]
+# Zone	NAME		STDOFF	RULES	FORMAT	[UNTIL]
 Zone	Asia/Yangon	6:24:47 -	LMT	1880        # or Rangoon
 			6:24:47	-	RMT	1920        # Rangoon local time
 			6:30	-	+0630	1942 May
@@ -584,7 +584,7 @@
 # that the sort of users who prefer Asia/Urumqi now typically ignored the
 # +08 mandate back then.

-# Zone	NAME		GMTOFF	RULES	FORMAT	[UNTIL]
+# Zone	NAME		STDOFF	RULES	FORMAT	[UNTIL]
 # Beijing time, used throughout China; represented by Shanghai.
 Zone	Asia/Shanghai	8:05:43	-	LMT	1901
 			8:00	Shang	C%sT	1949 May 28
@@ -675,11 +675,41 @@
 #   https://i.imgur.com/05KkvtC.png
 # * 1941-09-30, Hong Kong Daily Press, Winter Time Warning.
 #   https://i.imgur.com/dge4kFJ.png
-# Also, the Liberation day of Hong Kong after WWII which British rule
-# over the territory resumed was August 30, 1945, which I think should
-# be the termination date for the use of JST in the territory....
-
-# From Paul Eggert (2018-11-17):
+
+# From P Chan (2018-12-31):
+# * According to the Hong Kong Daylight-Saving Regulations, 1941, the
+#   1941 spring-forward transition was at 03:00.
+#	http://sunzi.lib.hku.hk/hkgro/view/g1941/304271.pdf
+#	http://sunzi.lib.hku.hk/hkgro/view/g1941/305516.pdf
+# * According to some articles from South China Morning Post, +08 was
+#   resumed on 1945-11-18 at 02:00.
+#	https://i.imgur.com/M2IsZ3c.png
+#	https://i.imgur.com/iOPqrVo.png
+#	https://i.imgur.com/fffcGDs.png
+# * Some newspapers ... said the 1946 spring-forward transition was on
+#   04-21 at 00:00.  The Kung Sheung Evening News 1946-04-20 (Chinese)
+#	https://i.imgur.com/ZSzent0.png
+#	https://mmis.hkpl.gov.hk///c/portal/cover?c=QF757YsWv5%2FH7zGe%2FKF%2BFLYsuqGhRBfe p.4
+#   The Kung Sheung Daily News 1946-04-21 (Chinese)
+#	https://i.imgur.com/7ecmRlcm.png
+#	https://mmis.hkpl.gov.hk///c/portal/cover?c=QF757YsWv5%2BQBGt1%2BwUj5qG2GqtwR3Wh p.4
+# * According to the Summer Time Ordinance (1946), the fallback
+#   transitions between 1946 and 1952 were at 03:30 Standard Time (+08)
+#	http://oelawhk.lib.hku.hk/archive/files/bb74b06a74d5294620a15de560ab33c6.pdf
+# * Some other laws and regulations related to DST from 1953 to 1979
+#   Summer Time Ordinance 1953
+#	https://i.imgur.com/IOlJMav.jpg
+#   Summer Time (Amendment) Ordinance 1965
+#	https://i.imgur.com/8rofeLa.jpg
+#   Interpretation and General Clauses Ordinance (1966)
+#	https://i.imgur.com/joy3msj.jpg
+#   Emergency (Summer Time) Regulation 1973 <https://i.imgur.com/OpRWrKz.jpg>
+#   Interpretation and General Clauses (Amendment) Ordinance 1977
+#	https://i.imgur.com/RaNqnc4.jpg
+#   Resolution of the Legislative Council passed on 9 May 1979
+#	https://www.legco.gov.hk/yr78-79/english/lc_sitg/hansard/h790509.pdf#page=39
+
+# From Paul Eggert (2019-05-31):
 # Here are the dates given at
 # https://www.hko.gov.hk/gts/time/Summertime.htm
 # as of 2014-06-19:
@@ -690,7 +720,7 @@
 # 1944        Whole year
 # 1945        Whole year
 # 1946        20 Apr to 1 Dec
-# 1947        13 Apr to 30 Dec
+# 1947        13 Apr to 30 Nov
 # 1948        2 May to 31 Oct
 # 1949        3 Apr to 30 Oct
 # 1950        2 Apr to 29 Oct
@@ -727,36 +757,28 @@
 # The page does not give times of day for transitions,
 # or dates for the 1942 and 1945 transitions.
 # The Japanese occupation of Hong Kong began 1941-12-25.
-# The Japanese surrender of Hong Kong was signed 1945-09-16; see:
-# Heaver S. The days after the Pacific war ended: unsettling times
-# in Hong Kong. Post Magazine. 2016-06-13.
-# https://www.scmp.com/magazines/post-magazine/article/1852990/days-after-pacific-war-ended-unsettling-times-hong-kong
-# For lack of anything better, use start of those days as the
-# transition times.

 # Rule	NAME	FROM	TO	TYPE	IN	ON	AT	SAVE	LETTER/S
-Rule	HK	1946	only	-	Apr	20	3:30	1:00	S
-Rule	HK	1946	only	-	Dec	1	3:30	0	-
-Rule	HK	1947	only	-	Apr	13	3:30	1:00	S
-Rule	HK	1947	only	-	Dec	30	3:30	0	-
-Rule	HK	1948	only	-	May	2	3:30	1:00	S
-Rule	HK	1948	1951	-	Oct	lastSun	3:30	0	-
-Rule	HK	1952	1953	-	Nov	Sun>=1	3:30	0	-
+Rule	HK	1946	only	-	Apr	21	0:00	1:00	S
+Rule	HK	1946	only	-	Dec	1	3:30s	0	-
+Rule	HK	1947	only	-	Apr	13	3:30s	1:00	S
+Rule	HK	1947	only	-	Nov	30	3:30s	0	-
+Rule	HK	1948	only	-	May	2	3:30s	1:00	S
+Rule	HK	1948	1952	-	Oct	Sun>=28	3:30s	0	-
 Rule	HK	1949	1953	-	Apr	Sun>=1	3:30	1:00	S
+Rule	HK	1953	1964	-	Oct	Sun>=31	3:30	0	-
 Rule	HK	1954	1964	-	Mar	Sun>=18	3:30	1:00	S
-Rule	HK	1954	only	-	Oct	31	3:30	0	-
-Rule	HK	1955	1964	-	Nov	Sun>=1	3:30	0	-
 Rule	HK	1965	1976	-	Apr	Sun>=16	3:30	1:00	S
 Rule	HK	1965	1976	-	Oct	Sun>=16	3:30	0	-
 Rule	HK	1973	only	-	Dec	30	3:30	1:00	S
-Rule	HK	1979	only	-	May	Sun>=8	3:30	1:00	S
-Rule	HK	1979	only	-	Oct	Sun>=16	3:30	0	-
-# Zone	NAME		GMTOFF	RULES	FORMAT	[UNTIL]
+Rule	HK	1979	only	-	May	13	3:30	1:00	S
+Rule	HK	1979	only	-	Oct	21	3:30	0	-
+# Zone	NAME		STDOFF	RULES	FORMAT	[UNTIL]
 Zone	Asia/Hong_Kong	7:36:42 -	LMT	1904 Oct 30  0:36:42
-			8:00	-	HKT	1941 Jun 15  3:30
+			8:00	-	HKT	1941 Jun 15  3:00
 			8:00	1:00	HKST	1941 Oct  1  4:00
 			8:30	-	HKT	1941 Dec 25
-			9:00	-	JST	1945 Sep 16
+			9:00	-	JST	1945 Nov 18  2:00
 			8:00	HK	HK%sT

 ###############################################################################
@@ -880,7 +902,7 @@
 Rule	Taiwan	1979	only	-	Jul	1	0:00	1:00	D
 Rule	Taiwan	1979	only	-	Oct	1	0:00	0	S

-# Zone	NAME		GMTOFF	RULES	FORMAT	[UNTIL]
+# Zone	NAME		STDOFF	RULES	FORMAT	[UNTIL]
 # Taipei or Taibei or T'ai-pei
 Zone	Asia/Taipei	8:06:00 -	LMT	1896 Jan  1
 			8:00	-	CST	1937 Oct  1
@@ -1018,7 +1040,7 @@
 Rule	Macau	1979	only	-	May	13	03:30	1:00	D
 Rule	Macau	1979	only	-	Oct	Sun>=16	03:30	0	S

-# Zone	NAME		GMTOFF	RULES	FORMAT	[UNTIL]
+# Zone	NAME		STDOFF	RULES	FORMAT	[UNTIL]
 Zone	Asia/Macau	7:34:10 -	LMT	1904 Oct 30
 			8:00	-	CST	1941 Dec 21 23:00
 			9:00	Macau	+09/+10	1945 Sep 30 24:00
@@ -1057,7 +1079,7 @@
 Rule	Cyprus	1978	only	-	Oct	2	0:00	0	-
 Rule	Cyprus	1979	1997	-	Sep	lastSun	0:00	0	-
 Rule	Cyprus	1981	1998	-	Mar	lastSun	0:00	1:00	S
-# Zone	NAME		GMTOFF	RULES	FORMAT	[UNTIL]
+# Zone	NAME		STDOFF	RULES	FORMAT	[UNTIL]
 Zone	Asia/Nicosia	2:13:28 -	LMT	1921 Nov 14
 			2:00	Cyprus	EE%sT	1998 Sep
 			2:00	EUAsia	EE%sT
@@ -1106,7 +1128,7 @@
 # Byalokoz 1919 says Georgia was 2:59:11.
 # Go with Byalokoz.

-# Zone	NAME		GMTOFF	RULES	FORMAT	[UNTIL]
+# Zone	NAME		STDOFF	RULES	FORMAT	[UNTIL]
 Zone	Asia/Tbilisi	2:59:11 -	LMT	1880
 			2:59:11	-	TBMT	1924 May  2 # Tbilisi Mean Time
 			3:00	-	+03	1957 Mar
@@ -1143,7 +1165,7 @@
 # which will be permanent, with no seasonal adjustment, will happen at
 # midnight on Saturday, September 16.

-# Zone	NAME		GMTOFF	RULES	FORMAT	[UNTIL]
+# Zone	NAME		STDOFF	RULES	FORMAT	[UNTIL]
 Zone	Asia/Dili	8:22:20 -	LMT	1912 Jan  1
 			8:00	-	+08	1942 Feb 21 23:00
 			9:00	-	+09	1976 May  3
@@ -1209,7 +1231,7 @@
 # time for 1870-1941.  Shanks is our only (and dubious) source for the
 # 1941-1945 data.

-# Zone	NAME		GMTOFF	RULES	FORMAT	[UNTIL]
+# Zone	NAME		STDOFF	RULES	FORMAT	[UNTIL]
 Zone	Asia/Kolkata	5:53:28 -	LMT	1854 Jun 28 # Kolkata
 			5:53:20	-	HMT	1870	    # Howrah Mean Time?
 			5:21:10	-	MMT	1906 Jan  1 # Madras local time
@@ -1261,7 +1283,7 @@
 # WITA - +08 - Waktu Indonesia Tengah (Indonesia central time)
 # WIT  - +09 - Waktu Indonesia Timur (Indonesia eastern time)
 #
-# Zone	NAME		GMTOFF	RULES	FORMAT	[UNTIL]
+# Zone	NAME		STDOFF	RULES	FORMAT	[UNTIL]
 # Java, Sumatra
 Zone Asia/Jakarta	7:07:12 -	LMT	1867 Aug 10
 # Shanks & Pottenger say the next transition was at 1924 Jan 1 0:13,
@@ -1337,9 +1359,9 @@
 # I used the following code in GNU Emacs 26.1 to generate the "Rule Iran"
 # lines from 2008 through 2087.  Emacs 26.1 uses Ed Reingold's
 # cal-persia implementation of Birashk's approximation, which in the
-# 2008-2087 range disagrees with the the astronomical Persian calendar
-# for Persian years 1404 (Gregorian 2025) and 1437 (Gregorian 2058),
-# so the following code special-case those years.  See Table 15.1, page 264, of:
+# 2008-2087 range disagrees with the astronomical Persian calendar
+# for Persian years 1404 (Gregorian 2025) and 1437 (Gregorian 2058), so
+# the following code special-cases those years.  See Table 15.1, page 264, of:
 # Edward M. Reingold and Nachum Dershowitz, Calendrical Calculations:
 # The Ultimate Edition, Cambridge University Press (2018).
 # https://www.cambridge.org/fr/academic/subjects/computer-science/computing-general-interest/calendrical-calculations-ultimate-edition-4th-edition
@@ -1533,7 +1555,7 @@
 Rule	Iran	2088	max	-	Mar	20	24:00	1:00	-
 Rule	Iran	2088	max	-	Sep	20	24:00	0	-

-# Zone	NAME		GMTOFF	RULES	FORMAT	[UNTIL]
+# Zone	NAME		STDOFF	RULES	FORMAT	[UNTIL]
 Zone	Asia/Tehran	3:25:44	-	LMT	1916
 			3:25:44	-	TMT	1946     # Tehran Mean Time
 			3:30	-	+0330	1977 Nov
@@ -1578,7 +1600,7 @@
 #
 Rule	Iraq	1991	2007	-	Apr	 1	3:00s	1:00	-
 Rule	Iraq	1991	2007	-	Oct	 1	3:00s	0	-
-# Zone	NAME		GMTOFF	RULES	FORMAT	[UNTIL]
+# Zone	NAME		STDOFF	RULES	FORMAT	[UNTIL]
 Zone	Asia/Baghdad	2:57:40	-	LMT	1890
 			2:57:36	-	BMT	1918     # Baghdad Mean Time?
 			3:00	-	+03	1982 May
@@ -1645,7 +1667,7 @@
 Rule	Zion	1975	only	-	Aug	31	0:00	0	S

 # From Alois Treindl (2019-03-06):
-# http://www.moin.gov.il/Documents/שעון קיץ/clock-50-years-7-2014.pdf
+# http://www.moin.gov.il/Documents/שעון%20קיץ/clock-50-years-7-2014.pdf
 # From Isaac Starkman (2019-03-06):
 # Summer time was in that period in 1980 and 1984, see
 # https://www.ynet.co.il/articles/0,7340,L-3951073,00.html
@@ -1783,32 +1805,15 @@
 #
 #	ftp://ftp.cs.huji.ac.il/pub/tz/announcements/2005+beyond.ps

-# From Paul Eggert (2012-10-26):
-# I used Ephraim Silverberg's dst-israel.el program
-# <ftp://ftp.cs.huji.ac.il/pub/tz/software/dst-israel.el> (2005-02-20)
-# along with Ed Reingold's cal-hebrew in GNU Emacs 21.4,
-# to generate the transitions from 2005 through 2012.
-# (I replaced "lastFri" with "Fri>=26" by hand.)
-# The spring transitions all correspond to the following Rule:
-#
-# Rule	Zion	2005	2012	-	Mar	Fri>=26	2:00	1:00	D
-#
-# but older zic implementations (e.g., Solaris 8) do not support
-# "Fri>=26" to mean April 1 in years like 2005, so for now we list the
-# springtime transitions explicitly.
-
 # Rule	NAME	FROM	TO	TYPE	IN	ON	AT	SAVE	LETTER/S
-Rule	Zion	2005	only	-	Apr	 1	2:00	1:00	D
+Rule	Zion	2005	2012	-	Apr	Fri<=1	2:00	1:00	D
 Rule	Zion	2005	only	-	Oct	 9	2:00	0	S
-Rule	Zion	2006	2010	-	Mar	Fri>=26	2:00	1:00	D
 Rule	Zion	2006	only	-	Oct	 1	2:00	0	S
 Rule	Zion	2007	only	-	Sep	16	2:00	0	S
 Rule	Zion	2008	only	-	Oct	 5	2:00	0	S
 Rule	Zion	2009	only	-	Sep	27	2:00	0	S
 Rule	Zion	2010	only	-	Sep	12	2:00	0	S
-Rule	Zion	2011	only	-	Apr	 1	2:00	1:00	D
 Rule	Zion	2011	only	-	Oct	 2	2:00	0	S
-Rule	Zion	2012	only	-	Mar	Fri>=26	2:00	1:00	D
 Rule	Zion	2012	only	-	Sep	23	2:00	0	S

 # From Ephraim Silverberg (2013-06-27):
@@ -1824,7 +1829,7 @@
 Rule	Zion	2013	max	-	Mar	Fri>=23	2:00	1:00	D
 Rule	Zion	2013	max	-	Oct	lastSun	2:00	0	S

-# Zone	NAME		GMTOFF	RULES	FORMAT	[UNTIL]
+# Zone	NAME		STDOFF	RULES	FORMAT	[UNTIL]
 Zone	Asia/Jerusalem	2:20:54 -	LMT	1880
 			2:20:40	-	JMT	1918 # Jerusalem Mean Time?
 			2:00	Zion	I%sT
@@ -1881,7 +1886,7 @@

 # Rule	NAME	FROM	TO	TYPE	IN	ON	AT	SAVE	LETTER/S
 Rule	Japan	1948	only	-	May	Sat>=1	24:00	1:00	D
-Rule	Japan	1948	1951	-	Sep	Sun>=9	 1:00	0	S
+Rule	Japan	1948	1951	-	Sep	Sat>=8	25:00	0	S
 Rule	Japan	1949	only	-	Apr	Sat>=1	24:00	1:00	D
 Rule	Japan	1950	1951	-	May	Sat>=1	24:00	1:00	D

@@ -1916,7 +1921,7 @@
 # Central Time (UT+9). The adoption began on Oct 1, 1937.
 # https://ja.wikisource.org/wiki/明治二十八年勅令第百六十七號標準時ニ關スル件中改正ノ件

-# Zone	NAME		GMTOFF	RULES	FORMAT	[UNTIL]
+# Zone	NAME		STDOFF	RULES	FORMAT	[UNTIL]
 Zone	Asia/Tokyo	9:18:59	-	LMT	1887 Dec 31 15:00u
 			9:00	Japan	J%sT
 # Since 1938, all Japanese possessions have been like Asia/Tokyo,
@@ -2019,7 +2024,7 @@
 Rule	Jordan	2013	only	-	Dec	20	0:00	0	-
 Rule	Jordan	2014	max	-	Mar	lastThu	24:00	1:00	S
 Rule	Jordan	2014	max	-	Oct	lastFri	0:00s	0	-
-# Zone	NAME		GMTOFF	RULES	FORMAT	[UNTIL]
+# Zone	NAME		STDOFF	RULES	FORMAT	[UNTIL]
 Zone	Asia/Amman	2:23:44 -	LMT	1931
 			2:00	Jordan	EE%sT

@@ -2060,8 +2065,8 @@
 # text.
 #
 # According to Izvestia newspaper No. 68 (23334) from 1991-03-20
-# (page 6; available at http://libinfo.org/newsr/newsr2574.djvu via
-# http://libinfo.org/index.php?id=58564) on 1991-03-31 at 2:00 during
+# -- page 6; available at http://libinfo.org/newsr/newsr2574.djvu via
+# http://libinfo.org/index.php?id=58564 -- on 1991-03-31 at 2:00 during
 # transition to "summer" time:
 # Republic of Georgia, Latvian SSR, Lithuanian SSR, SSR Moldova,
 # Estonian SSR; Komi ASSR; Kaliningrad oblast; Nenets autonomous okrug
@@ -2077,7 +2082,7 @@
 # Apparently there were last minute changes. Apparently Kazakh act No. 170
 # was one of such changes.
 #
-# https://ru.wikipedia.org/wiki/Декретное время
+# https://ru.wikipedia.org/wiki/Декретное_время
 # claims that Sovetskaya Rossiya newspaper on 1991-03-29 published that
 # Nenets autonomous okrug, Komi and Kazakhstan (excluding Uralsk oblast)
 # were to not move clocks and Uralsk oblast was to move clocks
@@ -2216,7 +2221,7 @@
 # UTC+6 to UTC+5 effective December 21st, 2018. The legal document is
 # located here: http://adilet.zan.kz/rus/docs/P1800000817 (russian language).

-# Zone	NAME		GMTOFF	RULES	FORMAT	[UNTIL]
+# Zone	NAME		STDOFF	RULES	FORMAT	[UNTIL]
 #
 # Almaty (formerly Alma-Ata), representing most locations in Kazakhstan
 # This includes KZ-AKM, KZ-ALA, KZ-ALM, KZ-AST, KZ-BAY, KZ-VOS, KZ-ZHA,
@@ -2318,7 +2323,7 @@
 Rule	Kyrgyz	1992	1996	-	Sep	lastSun	0:00	0	-
 Rule	Kyrgyz	1997	2005	-	Mar	lastSun	2:30	1:00	-
 Rule	Kyrgyz	1997	2004	-	Oct	lastSun	2:30	0	-
-# Zone	NAME		GMTOFF	RULES	FORMAT	[UNTIL]
+# Zone	NAME		STDOFF	RULES	FORMAT	[UNTIL]
 Zone	Asia/Bishkek	4:58:24 -	LMT	1924 May  2
 			5:00	-	+05	1930 Jun 21
 			6:00 RussiaAsia +06/+07	1991 Mar 31  2:00s
@@ -2433,7 +2438,7 @@
 # The BBC reported that the transition was from 23:30 to 24:00 today.
 # https://www.bbc.com/news/world-asia-44010705

-# Zone	NAME		GMTOFF	RULES	FORMAT	[UNTIL]
+# Zone	NAME		STDOFF	RULES	FORMAT	[UNTIL]
 Zone	Asia/Seoul	8:27:52	-	LMT	1908 Apr  1
 			8:30	-	KST	1912 Jan  1
 			9:00	-	JST	1945 Sep  8
@@ -2482,7 +2487,7 @@
 Rule	Lebanon	1993	max	-	Mar	lastSun	0:00	1:00	S
 Rule	Lebanon	1993	1998	-	Sep	lastSun	0:00	0	-
 Rule	Lebanon	1999	max	-	Oct	lastSun	0:00	0	-
-# Zone	NAME		GMTOFF	RULES	FORMAT	[UNTIL]
+# Zone	NAME		STDOFF	RULES	FORMAT	[UNTIL]
 Zone	Asia/Beirut	2:22:00 -	LMT	1880
 			2:00	Lebanon	EE%sT

@@ -2494,7 +2499,7 @@
 # peninsular Malaysia
 # taken from Mok Ly Yng (2003-10-30)
 # http://www.math.nus.edu.sg/aslaksen/teaching/timezone.html
-# Zone	NAME		GMTOFF	RULES	FORMAT	[UNTIL]
+# Zone	NAME		STDOFF	RULES	FORMAT	[UNTIL]
 Zone Asia/Kuala_Lumpur	6:46:46 -	LMT	1901 Jan  1
 			6:55:25	-	SMT	1905 Jun  1 # Singapore M.T.
 			7:00	-	+07	1933 Jan  1
@@ -2508,7 +2513,7 @@
 # From Paul Eggert (2014-08-12):
 # The data entries here are mostly from Shanks & Pottenger, but the 1942, 1945
 # and 1982 transition dates are from Mok Ly Yng.
-# Zone	NAME		GMTOFF	RULES	FORMAT	[UNTIL]
+# Zone	NAME		STDOFF	RULES	FORMAT	[UNTIL]
 Zone Asia/Kuching	7:21:20	-	LMT	1926 Mar
 			7:30	-	+0730	1933
 			8:00 NBorneo  +08/+0820	1942 Feb 16
@@ -2516,7 +2521,7 @@
 			8:00	-	+08

 # Maldives
-# Zone	NAME		GMTOFF	RULES	FORMAT	[UNTIL]
+# Zone	NAME		STDOFF	RULES	FORMAT	[UNTIL]
 Zone	Indian/Maldives	4:54:00 -	LMT	1880 # Malé
 			4:54:00	-	MMT	1960 # Malé Mean Time
 			5:00	-	+05
@@ -2659,7 +2664,7 @@
 Rule	Mongol	2015	2016	-	Mar	lastSat	2:00	1:00	-
 Rule	Mongol	2015	2016	-	Sep	lastSat	0:00	0	-

-# Zone	NAME		GMTOFF	RULES	FORMAT	[UNTIL]
+# Zone	NAME		STDOFF	RULES	FORMAT	[UNTIL]
 # Hovd, a.k.a. Chovd, Dund-Us, Dzhargalant, Khovd, Jirgalanta
 Zone	Asia/Hovd	6:06:36 -	LMT	1905 Aug
 			6:00	-	+06	1978
@@ -2677,7 +2682,7 @@
 			8:00	Mongol	+08/+09

 # Nepal
-# Zone	NAME		GMTOFF	RULES	FORMAT	[UNTIL]
+# Zone	NAME		STDOFF	RULES	FORMAT	[UNTIL]
 Zone	Asia/Kathmandu	5:41:16 -	LMT	1920
 			5:30	-	+0530	1986
 			5:45	-	+0545
@@ -2827,7 +2832,7 @@
 Rule Pakistan	2008	2009	-	Nov	1	0:00	0	-
 Rule Pakistan	2009	only	-	Apr	15	0:00	1:00	S

-# Zone	NAME		GMTOFF	RULES	FORMAT	[UNTIL]
+# Zone	NAME		STDOFF	RULES	FORMAT	[UNTIL]
 Zone	Asia/Karachi	4:28:12 -	LMT	1907
 			5:30	-	+0530	1942 Sep
 			5:30	1:00	+0630	1945 Oct 15
@@ -3114,13 +3119,21 @@
 # http://www.palestinecabinet.gov.ps/Website/AR/NDecrees/ViewFile.ashx?ID=e7a42ab7-ee23-435a-b9c8-a4f7e81f3817

 # From Even Scharning (2019-03-23):
-# DST in Palestine will start on 30 March this year, not 23 March as the time
-# zone database predicted.
-# https://ramallah.news/post/123610
+# http://pnn.ps/news/401130
+# http://palweather.ps/ar/node/50136.html
 #
-# From Tim Parenti (2019-03-23):
-# Combining this with the rules observed since 2016, adjust our spring
-# transition guess to Mar Sat>=24.
+# From Sharif Mustafa (2019-03-26):
+# The Palestinian cabinet announced today that the switch to DST will
+# be on Fri Mar 29th 2019 by advancing the clock by 60 minutes.
+# The decree signing date is Mar 12th but it was not published till today.
+# The decree does not specify the exact time of switch.
+# http://palestinecabinet.gov.ps/Website/AR/NDecrees/ViewFile.ashx?ID=e54e9ea1-50ee-4137-84df-0d6c78da259b
+#
+# From Even Scharning (2019-04-10):
+# Our source in Palestine said it happened Friday 29 at 00:00 local time....
+#
+# From Paul Eggert (2019-04-10):
+# For now, guess spring-ahead transitions are March's last Friday at 00:00.

 # Rule	NAME	FROM	TO	TYPE	IN	ON	AT	SAVE	LETTER/S
 Rule EgyptAsia	1957	only	-	May	10	0:00	1:00	S
@@ -3151,10 +3164,11 @@
 Rule Palestine	2013	only	-	Sep	Fri>=21	0:00	0	-
 Rule Palestine	2014	2015	-	Oct	Fri>=21	0:00	0	-
 Rule Palestine	2015	only	-	Mar	lastFri	24:00	1:00	S
-Rule Palestine	2016	max	-	Mar	Sat>=24	1:00	1:00	S
+Rule Palestine	2016	2018	-	Mar	Sat>=24	1:00	1:00	S
 Rule Palestine	2016	max	-	Oct	lastSat	1:00	0	-
-
-# Zone	NAME		GMTOFF	RULES	FORMAT	[UNTIL]
+Rule Palestine	2019	max	-	Mar	lastFri	0:00	1:00	S
+
+# Zone	NAME		STDOFF	RULES	FORMAT	[UNTIL]
 Zone	Asia/Gaza	2:17:52	-	LMT	1900 Oct
 			2:00	Zion	EET/EEST 1948 May 15
 			2:00 EgyptAsia	EE%sT	1967 Jun  5
@@ -3228,7 +3242,7 @@
 Rule	Phil	1954	only	-	Jul	1	0:00	0	S
 Rule	Phil	1978	only	-	Mar	22	0:00	1:00	D
 Rule	Phil	1978	only	-	Sep	21	0:00	0	S
-# Zone	NAME		GMTOFF	RULES	FORMAT	[UNTIL]
+# Zone	NAME		STDOFF	RULES	FORMAT	[UNTIL]
 Zone	Asia/Manila	-15:56:00 -	LMT	1844 Dec 31
 			8:04:00 -	LMT	1899 May 11
 			8:00	Phil	P%sT	1942 May
@@ -3236,7 +3250,7 @@
 			8:00	Phil	P%sT

 # Qatar
-# Zone	NAME		GMTOFF	RULES	FORMAT	[UNTIL]
+# Zone	NAME		STDOFF	RULES	FORMAT	[UNTIL]
 Zone	Asia/Qatar	3:26:08 -	LMT	1920     # Al Dawhah / Doha
 			4:00	-	+04	1972 Jun
 			3:00	-	+03
@@ -3284,7 +3298,7 @@
 # the country.  Presumably this is documenting airline time.  Ignore this,
 # as it's before our 1970 cutoff.
 #
-# Zone	NAME		GMTOFF	RULES	FORMAT	[UNTIL]
+# Zone	NAME		STDOFF	RULES	FORMAT	[UNTIL]
 Zone	Asia/Riyadh	3:06:52 -	LMT	1947 Mar 14
 			3:00	-	+03
 Link Asia/Riyadh Asia/Aden	# Yemen
@@ -3293,7 +3307,7 @@
 # Singapore
 # taken from Mok Ly Yng (2003-10-30)
 # http://www.math.nus.edu.sg/aslaksen/teaching/timezone.html
-# Zone	NAME		GMTOFF	RULES	FORMAT	[UNTIL]
+# Zone	NAME		STDOFF	RULES	FORMAT	[UNTIL]
 Zone	Asia/Singapore	6:55:25 -	LMT	1901 Jan  1
 			6:55:25	-	SMT	1905 Jun  1 # Singapore M.T.
 			7:00	-	+07	1933 Jan  1
@@ -3357,7 +3371,7 @@
 # even worse.  For now, let's use a numeric abbreviation; we can
 # switch to "SLST" if it catches on.

-# Zone	NAME		GMTOFF	RULES	FORMAT	[UNTIL]
+# Zone	NAME		STDOFF	RULES	FORMAT	[UNTIL]
 Zone	Asia/Colombo	5:19:24 -	LMT	1880
 			5:19:32	-	MMT	1906        # Moratuwa Mean Time
 			5:30	-	+0530	1942 Jan  5
@@ -3527,13 +3541,13 @@
 Rule	Syria	2012	max	-	Mar	lastFri	0:00	1:00	S
 Rule	Syria	2009	max	-	Oct	lastFri	0:00	0	-

-# Zone	NAME		GMTOFF	RULES	FORMAT	[UNTIL]
+# Zone	NAME		STDOFF	RULES	FORMAT	[UNTIL]
 Zone	Asia/Damascus	2:25:12 -	LMT	1920 # Dimashq
 			2:00	Syria	EE%sT

 # Tajikistan
 # From Shanks & Pottenger.
-# Zone	NAME		GMTOFF	RULES	FORMAT	[UNTIL]
+# Zone	NAME		STDOFF	RULES	FORMAT	[UNTIL]
 Zone	Asia/Dushanbe	4:35:12 -	LMT	1924 May  2
 			5:00	-	+05	1930 Jun 21
 			6:00 RussiaAsia +06/+07	1991 Mar 31  2:00s
@@ -3541,7 +3555,7 @@
 			5:00	-	+05

 # Thailand
-# Zone	NAME		GMTOFF	RULES	FORMAT	[UNTIL]
+# Zone	NAME		STDOFF	RULES	FORMAT	[UNTIL]
 Zone	Asia/Bangkok	6:42:04	-	LMT	1880
 			6:42:04	-	BMT	1920 Apr # Bangkok Mean Time
 			7:00	-	+07
@@ -3550,7 +3564,7 @@

 # Turkmenistan
 # From Shanks & Pottenger.
-# Zone	NAME		GMTOFF	RULES	FORMAT	[UNTIL]
+# Zone	NAME		STDOFF	RULES	FORMAT	[UNTIL]
 Zone	Asia/Ashgabat	3:53:32 -	LMT	1924 May  2 # or Ashkhabad
 			4:00	-	+04	1930 Jun 21
 			5:00 RussiaAsia	+05/+06	1991 Mar 31  2:00
@@ -3558,14 +3572,14 @@
 			5:00	-	+05

 # United Arab Emirates
-# Zone	NAME		GMTOFF	RULES	FORMAT	[UNTIL]
+# Zone	NAME		STDOFF	RULES	FORMAT	[UNTIL]
 Zone	Asia/Dubai	3:41:12 -	LMT	1920
 			4:00	-	+04
 Link Asia/Dubai Asia/Muscat	# Oman

 # Uzbekistan
 # Byalokoz 1919 says Uzbekistan was 4:27:53.
-# Zone	NAME		GMTOFF	RULES	FORMAT	[UNTIL]
+# Zone	NAME		STDOFF	RULES	FORMAT	[UNTIL]
 Zone	Asia/Samarkand	4:27:53 -	LMT	1924 May  2
 			4:00	-	+04	1930 Jun 21
 			5:00	-	+05	1981 Apr  1
@@ -3631,7 +3645,7 @@
 # Lê Thành Lân: "Lịch hai thế kỷ (1802-2010) và các lịch vĩnh cửu",
 # NXB Thuận Hoá, Huế, 1995.

-# Zone	NAME		GMTOFF	RULES	FORMAT	[UNTIL]
+# Zone	NAME		STDOFF	RULES	FORMAT	[UNTIL]
 Zone Asia/Ho_Chi_Minh	7:06:40 -	LMT	1906 Jul  1
 			7:06:30	-	PLMT	1911 May  1 # Phù Liễn MT
 			7:00	-	+07	1942 Dec 31 23:00
--- a/make/data/tzdata/australasia	Fri Aug 23 14:25:20 2019 +0100
+++ b/make/data/tzdata/australasia	Mon Aug 26 11:20:26 2019 +0530
@@ -48,7 +48,7 @@
 # says W Australia didn't use DST in 1943/1944.  Ignore Whitman's claim that
 # 1944/1945 was just like 1943/1944.

-# Zone	NAME		GMTOFF	RULES	FORMAT	[UNTIL]
+# Zone	NAME		STDOFF	RULES	FORMAT	[UNTIL]
 # Northern Territory
 Zone Australia/Darwin	 8:43:20 -	LMT	1895 Feb
 			 9:00	-	ACST	1899 May
@@ -125,7 +125,7 @@
 Rule	AS	2007	only	-	Mar	lastSun	2:00s	0	S
 Rule	AS	2008	max	-	Apr	Sun>=1	2:00s	0	S
 Rule	AS	2008	max	-	Oct	Sun>=1	2:00s	1:00	D
-# Zone	NAME		GMTOFF	RULES	FORMAT	[UNTIL]
+# Zone	NAME		STDOFF	RULES	FORMAT	[UNTIL]
 Zone Australia/Adelaide	9:14:20 -	LMT	1895 Feb
 			9:00	-	ACST	1899 May
 			9:30	Aus	AC%sT	1971
@@ -157,7 +157,7 @@
 Rule	AT	2006	only	-	Apr	Sun>=1	2:00s	0	S
 Rule	AT	2007	only	-	Mar	lastSun	2:00s	0	S
 Rule	AT	2008	max	-	Apr	Sun>=1	2:00s	0	S
-# Zone	NAME		GMTOFF	RULES	FORMAT	[UNTIL]
+# Zone	NAME		STDOFF	RULES	FORMAT	[UNTIL]
 Zone Australia/Hobart	9:49:16	-	LMT	1895 Sep
 			10:00	-	AEST	1916 Oct  1  2:00
 			10:00	1:00	AEDT	1917 Feb
@@ -185,7 +185,7 @@
 Rule	AV	2007	only	-	Mar	lastSun	2:00s	0	S
 Rule	AV	2008	max	-	Apr	Sun>=1	2:00s	0	S
 Rule	AV	2008	max	-	Oct	Sun>=1	2:00s	1:00	D
-# Zone	NAME		GMTOFF	RULES	FORMAT	[UNTIL]
+# Zone	NAME		STDOFF	RULES	FORMAT	[UNTIL]
 Zone Australia/Melbourne 9:39:52 -	LMT	1895 Feb
 			10:00	Aus	AE%sT	1971
 			10:00	AV	AE%sT
@@ -208,7 +208,7 @@
 Rule	AN	2007	only	-	Mar	lastSun	2:00s	0	S
 Rule	AN	2008	max	-	Apr	Sun>=1	2:00s	0	S
 Rule	AN	2008	max	-	Oct	Sun>=1	2:00s	1:00	D
-# Zone	NAME		GMTOFF	RULES	FORMAT	[UNTIL]
+# Zone	NAME		STDOFF	RULES	FORMAT	[UNTIL]
 Zone Australia/Sydney	10:04:52 -	LMT	1895 Feb
 			10:00	Aus	AE%sT	1971
 			10:00	AN	AE%sT
@@ -279,14 +279,14 @@
 			11:00	-	+11

 # Christmas
-# Zone	NAME		GMTOFF	RULES	FORMAT	[UNTIL]
+# Zone	NAME		STDOFF	RULES	FORMAT	[UNTIL]
 Zone Indian/Christmas	7:02:52 -	LMT	1895 Feb
 			7:00	-	+07

 # Cocos (Keeling) Is
 # These islands were ruled by the Ross family from about 1830 to 1978.
 # We don't know when standard time was introduced; for now, we guess 1900.
-# Zone	NAME		GMTOFF	RULES	FORMAT	[UNTIL]
+# Zone	NAME		STDOFF	RULES	FORMAT	[UNTIL]
 Zone	Indian/Cocos	6:27:40	-	LMT	1900
 			6:30	-	+0630

@@ -409,12 +409,12 @@
 Rule	Fiji	2014	only	-	Jan	Sun>=18	2:00	0	-
 Rule	Fiji	2014	max	-	Nov	Sun>=1	2:00	1:00	-
 Rule	Fiji	2015	max	-	Jan	Sun>=13	3:00	0	-
-# Zone	NAME		GMTOFF	RULES	FORMAT	[UNTIL]
+# Zone	NAME		STDOFF	RULES	FORMAT	[UNTIL]
 Zone	Pacific/Fiji	11:55:44 -	LMT	1915 Oct 26 # Suva
 			12:00	Fiji	+12/+13

 # French Polynesia
-# Zone	NAME		GMTOFF	RULES	FORMAT	[UNTIL]
+# Zone	NAME		STDOFF	RULES	FORMAT	[UNTIL]
 Zone	Pacific/Gambier	 -8:59:48 -	LMT	1912 Oct # Rikitea
 			 -9:00	-	-09
 Zone	Pacific/Marquesas -9:18:00 -	LMT	1912 Oct
@@ -457,7 +457,7 @@
 # http://documents.guam.gov/wp-content/uploads/E.O.-77-18-Guam-Standard-Time.pdf
 Rule	Guam	1977	only	-	Aug	28	2:00	0	S

-# Zone	NAME		GMTOFF	RULES	FORMAT	[UNTIL]
+# Zone	NAME		STDOFF	RULES	FORMAT	[UNTIL]
 Zone	Pacific/Guam	-14:21:00 -	LMT	1844 Dec 31
 			 9:39:00 -	LMT	1901        # Agana
 			10:00	-	GST	1941 Dec 10 # Guam
@@ -467,7 +467,7 @@
 Link Pacific/Guam Pacific/Saipan # N Mariana Is

 # Kiribati
-# Zone	NAME		GMTOFF	RULES	FORMAT	[UNTIL]
+# Zone	NAME		STDOFF	RULES	FORMAT	[UNTIL]
 Zone Pacific/Tarawa	 11:32:04 -	LMT	1901 # Bairiki
 			 12:00	-	+12
 Zone Pacific/Enderbury	-11:24:20 -	LMT	1901
@@ -483,7 +483,7 @@
 # See Pacific/Guam.

 # Marshall Is
-# Zone	NAME		GMTOFF	RULES	FORMAT	[UNTIL]
+# Zone	NAME		STDOFF	RULES	FORMAT	[UNTIL]
 Zone Pacific/Majuro	 11:24:48 -	LMT	1901
 			 11:00	-	+11	1914 Oct
 			  9:00	-	+09	1919 Feb  1
@@ -501,7 +501,7 @@
 			 12:00	-	+12

 # Micronesia
-# Zone	NAME		GMTOFF	RULES	FORMAT	[UNTIL]
+# Zone	NAME		STDOFF	RULES	FORMAT	[UNTIL]
 Zone Pacific/Chuuk	-13:52:52 -	LMT	1844 Dec 31
 			 10:07:08 -	LMT	1901
 			 10:00	-	+10	1914 Oct
@@ -529,7 +529,7 @@
 			 11:00	-	+11

 # Nauru
-# Zone	NAME		GMTOFF	RULES	FORMAT	[UNTIL]
+# Zone	NAME		STDOFF	RULES	FORMAT	[UNTIL]
 Zone	Pacific/Nauru	11:07:40 -	LMT	1921 Jan 15 # Uaobe
 			11:30	-	+1130	1942 Aug 29
 			 9:00	-	+09	1945 Sep  8
@@ -543,7 +543,7 @@
 Rule	NC	1996	only	-	Dec	 1	2:00s	1:00	-
 # Shanks & Pottenger say the following was at 2:00; go with IATA.
 Rule	NC	1997	only	-	Mar	 2	2:00s	0	-
-# Zone	NAME		GMTOFF	RULES	FORMAT	[UNTIL]
+# Zone	NAME		STDOFF	RULES	FORMAT	[UNTIL]
 Zone	Pacific/Noumea	11:05:48 -	LMT	1912 Jan 13 # Nouméa
 			11:00	NC	+11/+12

@@ -582,7 +582,7 @@
 Rule	Chatham	2007	max	-	Sep	lastSun	2:45s	1:00	-
 Rule	NZ	2008	max	-	Apr	Sun>=1	2:00s	0	S
 Rule	Chatham	2008	max	-	Apr	Sun>=1	2:45s	0	-
-# Zone	NAME		GMTOFF	RULES	FORMAT	[UNTIL]
+# Zone	NAME		STDOFF	RULES	FORMAT	[UNTIL]
 Zone Pacific/Auckland	11:39:04 -	LMT	1868 Nov  2
 			11:30	NZ	NZ%sT	1946 Jan  1
 			12:00	NZ	NZ%sT
@@ -608,7 +608,7 @@
 Rule	Cook	1978	only	-	Nov	12	0:00	0:30	-
 Rule	Cook	1979	1991	-	Mar	Sun>=1	0:00	0	-
 Rule	Cook	1979	1990	-	Oct	lastSun	0:00	0:30	-
-# Zone	NAME		GMTOFF	RULES	FORMAT	[UNTIL]
+# Zone	NAME		STDOFF	RULES	FORMAT	[UNTIL]
 Zone Pacific/Rarotonga	-10:39:04 -	LMT	1901        # Avarua
 			-10:30	-	-1030	1978 Nov 12
 			-10:00	Cook	-10/-0930
@@ -617,14 +617,14 @@


 # Niue
-# Zone	NAME		GMTOFF	RULES	FORMAT	[UNTIL]
+# Zone	NAME		STDOFF	RULES	FORMAT	[UNTIL]
 Zone	Pacific/Niue	-11:19:40 -	LMT	1901        # Alofi
 			-11:20	-	-1120	1951
 			-11:30	-	-1130	1978 Oct  1
 			-11:00	-	-11

 # Norfolk
-# Zone	NAME		GMTOFF	RULES	FORMAT	[UNTIL]
+# Zone	NAME		STDOFF	RULES	FORMAT	[UNTIL]
 Zone	Pacific/Norfolk	11:11:52 -	LMT	1901 # Kingston
 			11:12	-	+1112	1951
 			11:30	-	+1130	1974 Oct 27 02:00
@@ -633,13 +633,13 @@
 			11:00	-	+11

 # Palau (Belau)
-# Zone	NAME		GMTOFF	RULES	FORMAT	[UNTIL]
+# Zone	NAME		STDOFF	RULES	FORMAT	[UNTIL]
 Zone Pacific/Palau	-15:02:04 -	LMT	1844 Dec 31	# Koror
 			  8:57:56 -	LMT	1901
 			  9:00	-	+09

 # Papua New Guinea
-# Zone	NAME		GMTOFF	RULES	FORMAT	[UNTIL]
+# Zone	NAME		STDOFF	RULES	FORMAT	[UNTIL]
 Zone Pacific/Port_Moresby 9:48:40 -	LMT	1880
 			9:48:32	-	PMMT	1895 # Port Moresby Mean Time
 			10:00	-	+10
@@ -669,7 +669,7 @@
 			11:00	-	+11

 # Pitcairn
-# Zone	NAME		GMTOFF	RULES	FORMAT	[UNTIL]
+# Zone	NAME		STDOFF	RULES	FORMAT	[UNTIL]
 Zone Pacific/Pitcairn	-8:40:20 -	LMT	1901        # Adamstown
 			-8:30	-	-0830	1998 Apr 27  0:00
 			-8:00	-	-08
@@ -754,7 +754,7 @@
 Rule	WS	2011	only	-	Sep	lastSat	3:00	1	-
 Rule	WS	2012	max	-	Apr	Sun>=1	4:00	0	-
 Rule	WS	2012	max	-	Sep	lastSun	3:00	1	-
-# Zone	NAME		GMTOFF	RULES	FORMAT	[UNTIL]
+# Zone	NAME		STDOFF	RULES	FORMAT	[UNTIL]
 Zone Pacific/Apia	 12:33:04 -	LMT	1892 Jul  5
 			-11:26:56 -	LMT	1911
 			-11:30	-	-1130	1950
@@ -763,7 +763,7 @@

 # Solomon Is
 # excludes Bougainville, for which see Papua New Guinea
-# Zone	NAME		GMTOFF	RULES	FORMAT	[UNTIL]
+# Zone	NAME		STDOFF	RULES	FORMAT	[UNTIL]
 Zone Pacific/Guadalcanal 10:39:48 -	LMT	1912 Oct # Honiara
 			11:00	-	+11

@@ -786,7 +786,7 @@
 # was "11 hours slow on G.M.T."  Go with Thorsen and assume Shanks & Pottenger
 # are off by an hour starting in 1901.

-# Zone	NAME		GMTOFF	RULES	FORMAT	[UNTIL]
+# Zone	NAME		STDOFF	RULES	FORMAT	[UNTIL]
 Zone	Pacific/Fakaofo	-11:24:56 -	LMT	1901
 			-11:00	-	-11	2011 Dec 30
 			13:00	-	+13
@@ -799,14 +799,14 @@
 Rule	Tonga	2001	2002	-	Jan	lastSun	2:00	0	-
 Rule	Tonga	2016	only	-	Nov	Sun>=1	2:00	1:00	-
 Rule	Tonga	2017	only	-	Jan	Sun>=15	3:00	0	-
-# Zone	NAME		GMTOFF	RULES	FORMAT	[UNTIL]
+# Zone	NAME		STDOFF	RULES	FORMAT	[UNTIL]
 Zone Pacific/Tongatapu	12:19:20 -	LMT	1901
 			12:20	-	+1220	1941
 			13:00	-	+13	1999
 			13:00	Tonga	+13/+14

 # Tuvalu
-# Zone	NAME		GMTOFF	RULES	FORMAT	[UNTIL]
+# Zone	NAME		STDOFF	RULES	FORMAT	[UNTIL]
 Zone Pacific/Funafuti	11:56:52 -	LMT	1901
 			12:00	-	+12

@@ -867,7 +867,7 @@
 # uninhabited since World War II; was probably like Pacific/Kiritimati

 # Wake
-# Zone	NAME		GMTOFF	RULES	FORMAT	[UNTIL]
+# Zone	NAME		STDOFF	RULES	FORMAT	[UNTIL]
 Zone	Pacific/Wake	11:06:28 -	LMT	1901
 			12:00	-	+12

@@ -880,12 +880,12 @@
 Rule	Vanuatu	1985	1991	-	Sep	Sun>=23	0:00	1:00	-
 Rule	Vanuatu	1992	1993	-	Jan	Sun>=23	0:00	0	-
 Rule	Vanuatu	1992	only	-	Oct	Sun>=23	0:00	1:00	-
-# Zone	NAME		GMTOFF	RULES	FORMAT	[UNTIL]
+# Zone	NAME		STDOFF	RULES	FORMAT	[UNTIL]
 Zone	Pacific/Efate	11:13:16 -	LMT	1912 Jan 13 # Vila
 			11:00	Vanuatu	+11/+12

 # Wallis and Futuna
-# Zone	NAME		GMTOFF	RULES	FORMAT	[UNTIL]
+# Zone	NAME		STDOFF	RULES	FORMAT	[UNTIL]
 Zone	Pacific/Wallis	12:15:20 -	LMT	1901
 			12:00	-	+12

@@ -1271,6 +1271,22 @@
 # in WA or its introduction in SA had anything to do with the genesis
 # of this time zone.  My hunch is that it's been around since well
 # before 1975.  I remember seeing it noted on road maps decades ago.
+#
+# From Gilmore Davidson (2019-04-08):
+# https://www.abc.net.au/news/2019-04-08/this-remote-stretch-of-desert-has-its-own-custom-time-zone/10981000
+# ... include[s] a rough description of the geographical boundaries...
+# "The time zone exists for about 340 kilometres and takes in the tiny
+# roadhouse communities of Cocklebiddy, Madura, Eucla and Border Village."
+# ... and an indication that the zone has definitely been in existence
+# since before the 1970 cut-off of the database ...
+# From Paul Eggert (2019-05-17):
+# That ABC Esperance story by Christien de Garis also says:
+#    Although the Central Western Time Zone is not officially recognised (your
+#    phones won't automatically change), there is a sign instructing you which
+#    way to wind your clocks 45 minutes and scrawled underneath one of them in
+#    Texta is the word: 'Why'?
+#    "Good question," Mr Pike said.
+#    "I don't even know that, and it's been going for over 50 years."

 # From Paul Eggert (2006-12-15):
 # For lack of better info, assume the tradition dates back to the
@@ -1589,6 +1605,42 @@
 ###############################################################################


+# Bonin (Ogasawara) Islands and Marcus Island (Minami-Tori-shima)
+
+# From Wakaba (2019-01-28) via Phake Nick:
+# National Diet Library of Japan has several reports by Japanese Government
+# officers that describe the time used in islands when they visited there.
+# According to them (and other sources such as newspapers), standard time UTC
+# + 10 (JST + 1) and DST UTC + 11 (JST + 2) was used until its return to Japan
+# at 1968-06-26 00:00 JST.  The exact periods of DST are still unknown.
+# I guessed Guam, Mariana, and Bonin and Marcus districts might have
+# synchronized their DST periods, but reports imply they had their own
+# decisions, i.e. there were three or more different time zones....
+#
+# https://wiki.suikawiki.org/n/小笠原諸島の標準時
+
+# From Phake Nick (2019-02-12):
+# Because their last time change to return to Japanese time when they returned
+# to Japanese rule was right before 1970, ... per the current tz database
+# rule, the information doesn't warrant creation of a new timezone for Bonin
+# Islands itself and is thus as an anecdotal note for interest purpose only.
+# ... [The abovementioned link] described some special timekeeping phenomenon
+# regarding Marcus island, another remote island currently owned by Japanese
+# in the same administrative unit as Bonin Islands.  Many reports claim that
+# the American coastal guard on the American quarter of the island use its own
+# coastal guard time, and most sources describe the time as UTC+11, being two
+# hours faster than JST used by some Japanese personnel on the island.  Some
+# sites describe it as same as Wake Island/Guam time although it would be
+# incorrect to be same as Guam.  And then in a few Japanese governmental
+# report from 1980s (from National Institute of Information and Communications
+# Technology) regarding the construction of VLBI facility on the Marcus
+# Island, it claimed that there are three time standards being used on the
+# island at the time which include not just JST (UTC+9) or [US]CG time
+# (UTC+11) but also a JMSDF time (UTC+10) (Japan Maritime Self-Defense
+# Force).  Unfortunately there are no other sources that mentioned such time
+# and there are also no information on things like how the time was used.
+
+
 # Fiji

 # Howse writes (p 153) that in 1879 the British governor of Fiji
--- a/make/data/tzdata/europe	Fri Aug 23 14:25:20 2019 +0100
+++ b/make/data/tzdata/europe	Mon Aug 26 11:20:26 2019 +0530
@@ -145,7 +145,7 @@
 # position is 51° 28' 30" N, 0° 18' 45" W. The longitude should
 # be within about ±2". The Ordnance Survey grid reference is TQ172761.
 #
-# [This yields GMTOFF = -0:01:15 for London LMT in the 18th century.]
+# [This yields STDOFF = -0:01:15 for London LMT in the 18th century.]

 # From Paul Eggert (1993-11-18):
 #
@@ -523,7 +523,7 @@
 #
 # Use Europe/London for Jersey, Guernsey, and the Isle of Man.

-# Zone	NAME		GMTOFF	RULES	FORMAT	[UNTIL]
+# Zone	NAME		STDOFF	RULES	FORMAT	[UNTIL]
 Zone	Europe/London	-0:01:15 -	LMT	1847 Dec  1  0:00s
 			 0:00	GB-Eire	%s	1968 Oct 27
 			 1:00	-	BST	1971 Oct 31  2:00u
@@ -553,15 +553,15 @@
 # summer and negative daylight saving time in winter.  It is for when
 # negative SAVE values are used.
 # Rule	NAME	FROM	TO	TYPE	IN	ON	AT	SAVE	LETTER/S
-#Rule	Eire	1971	only	-	Oct	31	 2:00u	-1:00	-
-#Rule	Eire	1972	1980	-	Mar	Sun>=16	 2:00u	0	-
-#Rule	Eire	1972	1980	-	Oct	Sun>=23	 2:00u	-1:00	-
-#Rule	Eire	1981	max	-	Mar	lastSun	 1:00u	0	-
-#Rule	Eire	1981	1989	-	Oct	Sun>=23	 1:00u	-1:00	-
-#Rule	Eire	1990	1995	-	Oct	Sun>=22	 1:00u	-1:00	-
-#Rule	Eire	1996	max	-	Oct	lastSun	 1:00u	-1:00	-
-
-# Zone	NAME		GMTOFF	RULES	FORMAT	[UNTIL]
+Rule	Eire	1971	only	-	Oct	31	 2:00u	-1:00	-
+Rule	Eire	1972	1980	-	Mar	Sun>=16	 2:00u	0	-
+Rule	Eire	1972	1980	-	Oct	Sun>=23	 2:00u	-1:00	-
+Rule	Eire	1981	max	-	Mar	lastSun	 1:00u	0	-
+Rule	Eire	1981	1989	-	Oct	Sun>=23	 1:00u	-1:00	-
+Rule	Eire	1990	1995	-	Oct	Sun>=22	 1:00u	-1:00	-
+Rule	Eire	1996	max	-	Oct	lastSun	 1:00u	-1:00	-
+
+# Zone	NAME		STDOFF	RULES	FORMAT	[UNTIL]
 Zone	Europe/Dublin	-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
@@ -573,11 +573,11 @@
 			 0:00	-	GMT	1948 Apr 18  2:00s
 			 0:00	GB-Eire	GMT/IST	1968 Oct 27
 # The next line is for when negative SAVE values are used.
-#			 1:00	Eire	IST/GMT
+			 1:00	Eire	IST/GMT
 # These three lines are for when SAVE values are always nonnegative.
-			 1:00	-	IST	1971 Oct 31  2:00u
-			 0:00	GB-Eire	GMT/IST	1996
-			 0:00	EU	GMT/IST
+#			 1:00	-	IST	1971 Oct 31  2:00u
+#			 0:00	GB-Eire	GMT/IST	1996
+#			 0:00	EU	GMT/IST


 ###############################################################################
@@ -760,7 +760,7 @@

 # These are for backward compatibility with older versions.

-# Zone	NAME		GMTOFF	RULES	FORMAT	[UNTIL]
+# Zone	NAME		STDOFF	RULES	FORMAT	[UNTIL]
 Zone	WET		0:00	EU	WE%sT
 Zone	CET		1:00	C-Eur	CE%sT
 Zone	MET		1:00	C-Eur	ME%sT
@@ -820,14 +820,14 @@
 Rule	Albania	1983	only	-	Apr	18	0:00	1:00	S
 Rule	Albania	1983	only	-	Oct	 1	0:00	0	-
 Rule	Albania	1984	only	-	Apr	 1	0:00	1:00	S
-# Zone	NAME		GMTOFF	RULES	FORMAT	[UNTIL]
+# Zone	NAME		STDOFF	RULES	FORMAT	[UNTIL]
 Zone	Europe/Tirane	1:19:20 -	LMT	1914
 			1:00	-	CET	1940 Jun 16
 			1:00	Albania	CE%sT	1984 Jul
 			1:00	EU	CE%sT

 # Andorra
-# Zone	NAME		GMTOFF	RULES	FORMAT	[UNTIL]
+# Zone	NAME		STDOFF	RULES	FORMAT	[UNTIL]
 Zone	Europe/Andorra	0:06:04 -	LMT	1901
 			0:00	-	WET	1946 Sep 30
 			1:00	-	CET	1985 Mar 31  2:00
@@ -853,7 +853,7 @@
 Rule	Austria	1948	only	-	Apr	18	2:00s	1:00	S
 Rule	Austria	1980	only	-	Apr	 6	0:00	1:00	S
 Rule	Austria	1980	only	-	Sep	28	0:00	0	-
-# Zone	NAME		GMTOFF	RULES	FORMAT	[UNTIL]
+# Zone	NAME		STDOFF	RULES	FORMAT	[UNTIL]
 Zone	Europe/Vienna	1:05:21 -	LMT	1893 Apr
 			1:00	C-Eur	CE%sT	1920
 			1:00	Austria	CE%sT	1940 Apr  1  2:00s
@@ -885,7 +885,7 @@
 # Belarussian government decided against changing to winter time....
 # http://eng.belta.by/all_news/society/Belarus-decides-against-adjusting-time-in-Russias-wake_i_76335.html
 #
-# Zone	NAME		GMTOFF	RULES	FORMAT	[UNTIL]
+# Zone	NAME		STDOFF	RULES	FORMAT	[UNTIL]
 Zone	Europe/Minsk	1:50:16 -	LMT	1880
 			1:50	-	MMT	1924 May  2 # Minsk Mean Time
 			2:00	-	EET	1930 Jun 21
@@ -949,7 +949,7 @@
 Rule	Belgium	1945	only	-	Sep	16	 2:00s	0	-
 Rule	Belgium	1946	only	-	May	19	 2:00s	1:00	S
 Rule	Belgium	1946	only	-	Oct	 7	 2:00s	0	-
-# Zone	NAME		GMTOFF	RULES	FORMAT	[UNTIL]
+# Zone	NAME		STDOFF	RULES	FORMAT	[UNTIL]
 Zone	Europe/Brussels	0:17:30 -	LMT	1880
 			0:17:30	-	BMT	1892 May  1 12:00  # Brussels MT
 			0:00	-	WET	1914 Nov  8
@@ -976,7 +976,7 @@
 Rule	Bulg	1980	1982	-	Apr	Sat>=1	23:00	1:00	S
 Rule	Bulg	1980	only	-	Sep	29	 1:00	0	-
 Rule	Bulg	1981	only	-	Sep	27	 2:00	0	-
-# Zone	NAME		GMTOFF	RULES	FORMAT	[UNTIL]
+# Zone	NAME		STDOFF	RULES	FORMAT	[UNTIL]
 Zone	Europe/Sofia	1:33:16 -	LMT	1880
 			1:56:56	-	IMT	1894 Nov 30 # Istanbul MT?
 			2:00	-	EET	1942 Nov  2  3:00
@@ -1009,15 +1009,15 @@
 Rule	Czech	1946	1949	-	Oct	Sun>=1	2:00s	0	-
 Rule	Czech	1947	1948	-	Apr	Sun>=15	2:00s	1:00	S
 Rule	Czech	1949	only	-	Apr	 9	2:00s	1:00	S
-# Zone	NAME		GMTOFF	RULES	FORMAT	[UNTIL]
+# Zone	NAME		STDOFF	RULES	FORMAT	[UNTIL]
 Zone	Europe/Prague	0:57:44 -	LMT	1850
 			0:57:44	-	PMT	1891 Oct    # Prague Mean Time
 			1:00	C-Eur	CE%sT	1945 May  9
 			1:00	Czech	CE%sT	1946 Dec  1  3:00
 # Vanguard section, for zic and other parsers that support negative DST.
-#			1:00	-1:00	GMT	1947 Feb 23  2:00
+			1:00	-1:00	GMT	1947 Feb 23  2:00
 # Rearguard section, for parsers that do not support negative DST.
-			0:00	-	GMT	1947 Feb 23  2:00
+#			0:00	-	GMT	1947 Feb 23  2:00
 # End of rearguard section.
 			1:00	Czech	CE%sT	1979
 			1:00	EU	CE%sT
@@ -1071,7 +1071,7 @@
 Rule	Denmark	1948	only	-	May	 9	 2:00s	1:00	S
 Rule	Denmark	1948	only	-	Aug	 8	 2:00s	0	-
 #
-# Zone	NAME		GMTOFF	RULES	FORMAT	[UNTIL]
+# Zone	NAME		STDOFF	RULES	FORMAT	[UNTIL]
 Zone Europe/Copenhagen	 0:50:20 -	LMT	1890
 			 0:50:20 -	CMT	1894 Jan  1 # Copenhagen MT
 			 1:00	Denmark	CE%sT	1942 Nov  2  2:00s
@@ -1168,7 +1168,7 @@
 Rule	Thule	2007	max	-	Mar	Sun>=8	2:00	1:00	D
 Rule	Thule	2007	max	-	Nov	Sun>=1	2:00	0	S
 #
-# Zone	NAME		GMTOFF	RULES	FORMAT	[UNTIL]
+# Zone	NAME		STDOFF	RULES	FORMAT	[UNTIL]
 Zone America/Danmarkshavn -1:14:40 -	LMT	1916 Jul 28
 			-3:00	-	-03	1980 Apr  6  2:00
 			-3:00	EU	-03/-02	1996
@@ -1234,7 +1234,7 @@
 # From Urmet Jänes (2002-03-28):
 # The legislative reference is Government decree No. 84 on 2002-02-21.

-# Zone	NAME		GMTOFF	RULES	FORMAT	[UNTIL]
+# Zone	NAME		STDOFF	RULES	FORMAT	[UNTIL]
 Zone	Europe/Tallinn	1:39:00	-	LMT	1880
 			1:39:00	-	TMT	1918 Feb    # Tallinn Mean Time
 			1:00	C-Eur	CE%sT	1919 Jul
@@ -1297,7 +1297,7 @@
 # Milne says Helsinki (Helsingfors) time was 1:39:49.2 (official document);
 # round to nearest.

-# Zone	NAME		GMTOFF	RULES	FORMAT	[UNTIL]
+# Zone	NAME		STDOFF	RULES	FORMAT	[UNTIL]
 Zone	Europe/Helsinki	1:39:49 -	LMT	1878 May 31
 			1:39:49	-	HMT	1921 May    # Helsinki Mean Time
 			2:00	Finland	EE%sT	1983
@@ -1387,7 +1387,7 @@
 # but Howse quotes the actual French legislation as saying 0:09:21.
 # Go with Howse.  Howse writes that the time in France was officially based
 # on PMT-0:09:21 until 1978-08-09, when the time base finally switched to UTC.
-# Zone	NAME		GMTOFF	RULES	FORMAT	[UNTIL]
+# Zone	NAME		STDOFF	RULES	FORMAT	[UNTIL]
 Zone	Europe/Paris	0:09:21 -	LMT	1891 Mar 15  0:01
 			0:09:21	-	PMT	1911 Mar 11  0:01 # Paris MT
 # Shanks & Pottenger give 1940 Jun 14 0:00; go with Excoffier and Le Corre.
@@ -1435,7 +1435,7 @@
 Rule SovietZone	1945	only	-	Sep	24	3:00	1:00	S
 Rule SovietZone	1945	only	-	Nov	18	2:00s	0	-

-# Zone	NAME		GMTOFF	RULES	FORMAT	[UNTIL]
+# Zone	NAME		STDOFF	RULES	FORMAT	[UNTIL]
 Zone	Europe/Berlin	0:53:28 -	LMT	1893 Apr
 			1:00	C-Eur	CE%sT	1945 May 24  2:00
 			1:00 SovietZone	CE%sT	1946
@@ -1463,7 +1463,7 @@
 # is in Europe.  Our reference location Tbilisi is in the Asian part.

 # Gibraltar
-# Zone	NAME		GMTOFF	RULES	FORMAT	[UNTIL]
+# Zone	NAME		STDOFF	RULES	FORMAT	[UNTIL]
 Zone Europe/Gibraltar	-0:21:24 -	LMT	1880 Aug  2  0:00s
 			0:00	GB-Eire	%s	1957 Apr 14  2:00
 			1:00	-	CET	1982
@@ -1494,7 +1494,7 @@
 Rule	Greece	1979	only	-	Sep	29	2:00	0	-
 Rule	Greece	1980	only	-	Apr	 1	0:00	1:00	S
 Rule	Greece	1980	only	-	Sep	28	0:00	0	-
-# Zone	NAME		GMTOFF	RULES	FORMAT	[UNTIL]
+# Zone	NAME		STDOFF	RULES	FORMAT	[UNTIL]
 Zone	Europe/Athens	1:34:52 -	LMT	1895 Sep 14
 			1:34:52	-	AMT	1916 Jul 28  0:01 # Athens MT
 			2:00	Greece	EE%sT	1941 Apr 30
@@ -1531,7 +1531,7 @@
 Rule	Hungary	1957	only	-	Jun	Sun>=1	 1:00	1:00	S
 Rule	Hungary	1957	only	-	Sep	lastSun	 3:00	0	-
 Rule	Hungary	1980	only	-	Apr	 6	 1:00	1:00	S
-# Zone	NAME		GMTOFF	RULES	FORMAT	[UNTIL]
+# Zone	NAME		STDOFF	RULES	FORMAT	[UNTIL]
 Zone	Europe/Budapest	1:16:20 -	LMT	1890 Oct
 			1:00	C-Eur	CE%sT	1918
 			1:00	Hungary	CE%sT	1941 Apr  8
@@ -1592,7 +1592,7 @@
 Rule	Iceland	1949	only	-	Oct	30	 1:00s	0	-
 Rule	Iceland	1950	1966	-	Oct	Sun>=22	 1:00s	0	-
 Rule	Iceland	1967	only	-	Oct	29	 1:00s	0	-
-# Zone	NAME		GMTOFF	RULES	FORMAT	[UNTIL]
+# Zone	NAME		STDOFF	RULES	FORMAT	[UNTIL]
 Zone Atlantic/Reykjavik	-1:28	-	LMT	1908
 			-1:00	Iceland	-01/+00	1968 Apr  7  1:00s
 			 0:00	-	GMT
@@ -1606,6 +1606,25 @@
 # But these events all occurred before the 1970 cutoff,
 # so record only the time in Rome.
 #
+# From Stephen Trainor (2019-05-06):
+# http://www.ac-ilsestante.it/MERIDIANE/ora_legale/ORA_LEGALE_ESTIVA_IN_ITALIA.htm
+# ... the [1866] law went into effect on 12 December 1866, rather than
+# the date of the decree (22 Sep 1866)
+# https://web.archive.org/web/20070824155341/http://www.iav.it/planetario/didastro/didastro/english.htm
+# ... "In Italy in 1866 there were 6 railway times (Torino, Verona, Firenze,
+# Roma, Napoli, Palermo). On that year it was decided to unify them, adopting
+# the average time of Rome (even if this city was not yet part of the
+# kingdom).  On the 12th December 1866, on the starting of the winter time
+# table, it took effect in the railways, the post office and the telegraph,
+# not only for the internal service but also for the public....  Milano set
+# the public watches on the Rome time on the same day (12th December 1866),
+# Torino and Bologna on the 1st January 1867, Venezia the 1st May 1880 and the
+# last city was Cagliari in 1886."
+#
+# From Luigi Rosa (2019-05-07):
+# this is the scan of the decree:
+# http://www.radiomarconi.com/marconi/filopanti/1866c.jpg
+#
 # From Michael Deckers (2016-10-24):
 # http://www.ac-ilsestante.it/MERIDIANE/ora_legale quotes a law of 1893-08-10
 # ... [translated as] "The preceding dispositions will enter into
@@ -1616,6 +1635,7 @@
 # The authoritative source for time in Italy is the national metrological
 # institute, which has a summary page of historical DST data at
 # http://www.inrim.it/res/tf/ora_legale_i.shtml
+# [now at http://oldsite.inrim.it/res/tf/ora_legale_i.shtml as of 2017]
 # (2016-10-24):
 # http://www.renzobaldini.it/le-ore-legali-in-italia/
 # has still different data for 1944.  It divides Italy in two, as
@@ -1679,8 +1699,8 @@
 Rule	Italy	1977	1979	-	May	Sun>=22	 0:00s	1:00	S
 Rule	Italy	1978	only	-	Oct	 1	 0:00s	0	-
 Rule	Italy	1979	only	-	Sep	30	 0:00s	0	-
-# Zone	NAME		GMTOFF	RULES	FORMAT	[UNTIL]
-Zone	Europe/Rome	0:49:56 -	LMT	1866 Sep 22
+# Zone	NAME		STDOFF	RULES	FORMAT	[UNTIL]
+Zone	Europe/Rome	0:49:56 -	LMT	1866 Dec 12
 			0:49:56	-	RMT	1893 Oct 31 23:49:56 # Rome Mean
 			1:00	Italy	CE%sT	1943 Sep 10
 			1:00	C-Eur	CE%sT	1944 Jun  4
@@ -1755,7 +1775,7 @@
 # Byalokoz 1919 says Latvia was 1:36:34.
 # Go with Byalokoz.

-# Zone	NAME		GMTOFF	RULES	FORMAT	[UNTIL]
+# Zone	NAME		STDOFF	RULES	FORMAT	[UNTIL]
 Zone	Europe/Riga	1:36:34	-	LMT	1880
 			1:36:34	-	RMT	1918 Apr 15  2:00 # Riga MT
 			1:36:34	1:00	LST	1918 Sep 16  3:00 # Latvian ST
@@ -1825,7 +1845,7 @@
 # http://www.lrvk.lt/nut/11/n1749.htm


-# Zone	NAME		GMTOFF	RULES	FORMAT	[UNTIL]
+# Zone	NAME		STDOFF	RULES	FORMAT	[UNTIL]
 Zone	Europe/Vilnius	1:41:16	-	LMT	1880
 			1:24:00	-	WMT	1917        # Warsaw Mean Time
 			1:35:36	-	KMT	1919 Oct 10 # Kaunas Mean Time
@@ -1869,7 +1889,7 @@
 Rule	Lux	1927	only	-	Apr	 9	23:00	1:00	S
 Rule	Lux	1928	only	-	Apr	14	23:00	1:00	S
 Rule	Lux	1929	only	-	Apr	20	23:00	1:00	S
-# Zone	NAME		GMTOFF	RULES	FORMAT	[UNTIL]
+# Zone	NAME		STDOFF	RULES	FORMAT	[UNTIL]
 Zone Europe/Luxembourg	0:24:36 -	LMT	1904 Jun
 			1:00	Lux	CE%sT	1918 Nov 25
 			0:00	Lux	WE%sT	1929 Oct  6  2:00s
@@ -1894,7 +1914,7 @@
 Rule	Malta	1975	1979	-	Apr	Sun>=15	2:00	1:00	S
 Rule	Malta	1975	1980	-	Sep	Sun>=15	2:00	0	-
 Rule	Malta	1980	only	-	Mar	31	2:00	1:00	S
-# Zone	NAME		GMTOFF	RULES	FORMAT	[UNTIL]
+# Zone	NAME		STDOFF	RULES	FORMAT	[UNTIL]
 Zone	Europe/Malta	0:58:04 -	LMT	1893 Nov  2  0:00s # Valletta
 			1:00	Italy	CE%sT	1973 Mar 31
 			1:00	Malta	CE%sT	1981
@@ -1963,7 +1983,7 @@
 Rule	Moldova	1997	max	-	Mar	lastSun	 2:00	1:00	S
 Rule	Moldova	1997	max	-	Oct	lastSun	 3:00	0	-

-# Zone	NAME		GMTOFF	RULES	FORMAT	[UNTIL]
+# Zone	NAME		STDOFF	RULES	FORMAT	[UNTIL]
 Zone	Europe/Chisinau	1:55:20 -	LMT	1880
 			1:55	-	CMT	1918 Feb 15 # Chisinau MT
 			1:44:24	-	BMT	1931 Jul 24 # Bucharest MT
@@ -1979,7 +1999,7 @@
 # Monaco
 # Shanks & Pottenger give 0:09:20 for Paris Mean Time; go with Howse's
 # more precise 0:09:21.
-# Zone	NAME		GMTOFF	RULES	FORMAT	[UNTIL]
+# Zone	NAME		STDOFF	RULES	FORMAT	[UNTIL]
 Zone	Europe/Monaco	0:29:32 -	LMT	1891 Mar 15
 			0:09:21	-	PMT	1911 Mar 11 # Paris Mean Time
 			0:00	France	WE%sT	1945 Sep 16  3:00
@@ -2054,8 +2074,8 @@
 Rule	Neth	1945	only	-	Sep	16	2:00s	0	-
 #
 # Amsterdam Mean Time was +00:19:32.13, but the .13 is omitted
-# below because the current format requires GMTOFF to be an integer.
-# Zone	NAME		GMTOFF	RULES	FORMAT	[UNTIL]
+# below because the current format requires STDOFF to be an integer.
+# Zone	NAME		STDOFF	RULES	FORMAT	[UNTIL]
 Zone Europe/Amsterdam	0:19:32 -	LMT	1835
 			0:19:32	Neth	%s	1937 Jul  1
 			0:20	Neth +0020/+0120 1940 May 16  0:00
@@ -2074,7 +2094,7 @@
 Rule	Norway	1959	1964	-	Mar	Sun>=15	2:00s	1:00	S
 Rule	Norway	1959	1965	-	Sep	Sun>=15	2:00s	0	-
 Rule	Norway	1965	only	-	Apr	25	2:00s	1:00	S
-# Zone	NAME		GMTOFF	RULES	FORMAT	[UNTIL]
+# Zone	NAME		STDOFF	RULES	FORMAT	[UNTIL]
 Zone	Europe/Oslo	0:43:00 -	LMT	1895 Jan  1
 			1:00	Norway	CE%sT	1940 Aug 10 23:00
 			1:00	C-Eur	CE%sT	1945 Apr  2  2:00
@@ -2165,7 +2185,7 @@
 Rule	Poland	1960	only	-	Apr	 3	1:00s	1:00	S
 Rule	Poland	1961	1964	-	May	lastSun	1:00s	1:00	S
 Rule	Poland	1962	1964	-	Sep	lastSun	1:00s	0	-
-# Zone	NAME		GMTOFF	RULES	FORMAT	[UNTIL]
+# Zone	NAME		STDOFF	RULES	FORMAT	[UNTIL]
 Zone	Europe/Warsaw	1:24:00 -	LMT	1880
 			1:24:00	-	WMT	1915 Aug  5 # Warsaw Mean Time
 			1:00	C-Eur	CE%sT	1918 Sep 16  3:00
@@ -2270,7 +2290,7 @@
 Rule	Port	1981	1982	-	Mar	lastSun	 1:00s	1:00	S
 Rule	Port	1983	only	-	Mar	lastSun	 2:00s	1:00	S
 #
-# Zone	NAME		GMTOFF	RULES	FORMAT	[UNTIL]
+# Zone	NAME		STDOFF	RULES	FORMAT	[UNTIL]
 Zone	Europe/Lisbon	-0:36:45 -	LMT	1884
 			-0:36:45 -	LMT	1912 Jan  1  0:00u # Lisbon MT
 			 0:00	Port	WE%sT	1966 Apr  3  2:00
@@ -2329,7 +2349,7 @@
 Rule	Romania	1980	only	-	Sep	lastSun	 1:00	0	-
 Rule	Romania	1991	1993	-	Mar	lastSun	 0:00s	1:00	S
 Rule	Romania	1991	1993	-	Sep	lastSun	 0:00s	0	-
-# Zone	NAME		GMTOFF	RULES	FORMAT	[UNTIL]
+# Zone	NAME		STDOFF	RULES	FORMAT	[UNTIL]
 Zone Europe/Bucharest	1:44:24 -	LMT	1891 Oct
 			1:44:24	-	BMT	1931 Jul 24 # Bucharest MT
 			2:00	Romania	EE%sT	1981 Mar 29  2:00s
@@ -3368,7 +3388,7 @@
 # See Europe/Rome.

 # Serbia
-# Zone	NAME		GMTOFF	RULES	FORMAT	[UNTIL]
+# Zone	NAME		STDOFF	RULES	FORMAT	[UNTIL]
 Zone	Europe/Belgrade	1:22:00	-	LMT	1884
 			1:00	-	CET	1941 Apr 18 23:00
 			1:00	C-Eur	CE%sT	1945
@@ -3474,7 +3494,7 @@
 Rule SpainAfrica 1977	only	-	Sep	28	 0:00	0	-
 Rule SpainAfrica 1978	only	-	Jun	 1	 0:00	1:00	S
 Rule SpainAfrica 1978	only	-	Aug	 4	 0:00	0	-
-# Zone	NAME		GMTOFF	RULES	FORMAT	[UNTIL]
+# Zone	NAME		STDOFF	RULES	FORMAT	[UNTIL]
 Zone	Europe/Madrid	-0:14:44 -	LMT	1900 Dec 31 23:45:16
 			 0:00	Spain	WE%sT	1940 Mar 16 23:00
 			 1:00	Spain	CE%sT	1979
@@ -3542,7 +3562,7 @@
 #
 # Source: The newspaper "Dagens Nyheter", 1916-10-01, page 7 upper left.

-# Zone	NAME		GMTOFF	RULES	FORMAT	[UNTIL]
+# Zone	NAME		STDOFF	RULES	FORMAT	[UNTIL]
 Zone Europe/Stockholm	1:12:12 -	LMT	1879 Jan  1
 			1:00:14	-	SET	1900 Jan  1 # Swedish Time
 			1:00	-	CET	1916 May 14 23:00
@@ -3645,7 +3665,7 @@
 # Rule	NAME	FROM	TO	TYPE	IN	ON	AT	SAVE	LETTER/S
 Rule	Swiss	1941	1942	-	May	Mon>=1	1:00	1:00	S
 Rule	Swiss	1941	1942	-	Oct	Mon>=1	2:00	0	-
-# Zone	NAME		GMTOFF	RULES	FORMAT	[UNTIL]
+# Zone	NAME		STDOFF	RULES	FORMAT	[UNTIL]
 Zone	Europe/Zurich	0:34:08 -	LMT	1853 Jul 16 # See above comment.
 			0:29:46	-	BMT	1894 Jun    # Bern Mean Time
 			1:00	Swiss	CE%sT	1981
@@ -3795,7 +3815,7 @@
 Rule	Turkey	1994	only	-	Mar	20	1:00s	1:00	S
 Rule	Turkey	1995	2006	-	Mar	lastSun	1:00s	1:00	S
 Rule	Turkey	1996	2006	-	Oct	lastSun	1:00s	0	-
-# Zone	NAME		GMTOFF	RULES	FORMAT	[UNTIL]
+# Zone	NAME		STDOFF	RULES	FORMAT	[UNTIL]
 Zone	Europe/Istanbul	1:55:52 -	LMT	1880
 			1:56:56	-	IMT	1910 Oct # Istanbul Mean Time?
 			2:00	Turkey	EE%sT	1978 Oct 15
@@ -3892,16 +3912,8 @@
 # controversial, and some day "Kyiv" may become substantially more popular in
 # English; in the meantime, stick with the traditional English "Kiev" as that
 # means less disruption for our users.
-#
-# Anyway, none of the common English-language spellings (Kiev, Kyiv, Kieff,
-# Kijeff, Kijev, Kiyef, Kiyeff) do justice to the common pronunciation in
-# Ukrainian, namely [ˈkɪjiu̯] (IPA).  This pronunciation has nothing like an
-# English "v" or "f", and instead trails off with what an English-speaker
-# would call a demure "oo" sound, and it would would be better anglicized as
-# "Kuiyu".  Here's a sound file, if you would like to do as the Kuiyuvians do:
-# https://commons.wikimedia.org/wiki/File:Uk-Київ.ogg
-
-# Zone	NAME		GMTOFF	RULES	FORMAT	[UNTIL]
+
+# Zone	NAME		STDOFF	RULES	FORMAT	[UNTIL]
 # This represents most of Ukraine.  See above for the spelling of "Kiev".
 Zone Europe/Kiev	2:02:04 -	LMT	1880
 			2:02:04	-	KMT	1924 May  2 # Kiev Mean Time
--- a/make/data/tzdata/factory	Fri Aug 23 14:25:20 2019 +0100
+++ b/make/data/tzdata/factory	Mon Aug 26 11:20:26 2019 +0530
@@ -31,5 +31,5 @@
 # time zone abbreviation "-00", indicating that the actual time zone
 # is unknown.

-# Zone	NAME	GMTOFF	RULES	FORMAT
+# Zone	NAME	STDOFF	RULES	FORMAT
 Zone	Factory	0	-	-00
--- a/make/data/tzdata/northamerica	Fri Aug 23 14:25:20 2019 +0100
+++ b/make/data/tzdata/northamerica	Mon Aug 26 11:20:26 2019 +0530
@@ -116,10 +116,33 @@
 # was the first nationwide legal time standard, and apparently
 # time was just called "Standard Time" or "Daylight Saving Time".

-# From Arthur David Olson:
-# US Daylight Saving Time ended on the last Sunday of *October* in 1974.
-# See, for example, the front page of the Saturday, 1974-10-26
-# and Sunday, 1974-10-27 editions of the Washington Post.
+# From Paul Eggert (2019-06-04):
+# Here is the legal basis for the US federal rules.
+# * Public Law 65-106 (1918-03-19) implemented standard and daylight saving
+#   time for the first time across the US, springing forward on March's last
+#   Sunday and falling back on October's last Sunday.
+#   https://www.loc.gov/law/help/statutes-at-large/65th-congress/session-2/c65s2ch24.pdf
+# * Public Law 66-40 (1919-08-20) repealed DST on October 1919's last Sunday.
+#   https://www.loc.gov/law/help/statutes-at-large/66th-congress/session-1/c66s1ch51.pdf
+# * Public Law 77-403 (1942-01-20) started wartime DST on 1942-02-09.
+#   https://www.loc.gov/law/help/statutes-at-large/77th-congress/session-2/c77s2ch7.pdf
+# * Public Law 79-187 (1945-09-25) ended wartime DST on 1945-09-30.
+#   https://www.loc.gov/law/help/statutes-at-large/79th-congress/session-1/c79s1ch388.pdf
+# * Public Law 89-387 (1966-04-13) reinstituted a national standard for DST,
+#   from April's last Sunday to October's last Sunday, effective 1967.
+#   https://www.govinfo.gov/content/pkg/STATUTE-80/pdf/STATUTE-80-Pg107.pdf
+# * Public Law 93-182 (1973-12-15) moved the 1974 spring-forward to 01-06.
+#   https://www.govinfo.gov/content/pkg/STATUTE-87/pdf/STATUTE-87-Pg707.pdf
+# * Public Law 93-434 (1974-10-05) moved the 1975 spring-forward to
+#   February's last Sunday.
+#   https://www.govinfo.gov/content/pkg/STATUTE-88/pdf/STATUTE-88-Pg1209.pdf
+# * Public Law 99-359 (1986-07-08) moved the spring-forward to April's first
+#   Sunday.
+#   https://www.govinfo.gov/content/pkg/STATUTE-100/pdf/STATUTE-100-Pg764.pdf
+# * Public Law 109-58 (2005-08-08), effective 2007, moved the spring-forward
+#   to March's second Sunday and the fall-back to November's first Sunday.
+#   https://www.govinfo.gov/content/pkg/PLAW-109publ58/pdf/PLAW-109publ58.pdf
+# All transitions are at 02:00 local time.

 # From Arthur David Olson:
 # Before the Uniform Time Act of 1966 took effect in 1967, observance of
@@ -175,11 +198,11 @@
 Rule	US	1918	1919	-	Oct	lastSun	2:00	0	S
 Rule	US	1942	only	-	Feb	9	2:00	1:00	W # War
 Rule	US	1945	only	-	Aug	14	23:00u	1:00	P # Peace
-Rule	US	1945	only	-	Sep	lastSun	2:00	0	S
+Rule	US	1945	only	-	Sep	30	2:00	0	S
 Rule	US	1967	2006	-	Oct	lastSun	2:00	0	S
 Rule	US	1967	1973	-	Apr	lastSun	2:00	1:00	D
 Rule	US	1974	only	-	Jan	6	2:00	1:00	D
-Rule	US	1975	only	-	Feb	23	2:00	1:00	D
+Rule	US	1975	only	-	Feb	lastSun	2:00	1:00	D
 Rule	US	1976	1986	-	Apr	lastSun	2:00	1:00	D
 Rule	US	1987	2006	-	Apr	Sun>=1	2:00	1:00	D
 Rule	US	2007	max	-	Mar	Sun>=8	2:00	1:00	D
@@ -196,7 +219,7 @@
 # increase the chances that they'll actually get compiled and to
 # avoid the need to duplicate the US rules in another file.

-# Zone	NAME		GMTOFF	RULES	FORMAT	[UNTIL]
+# Zone	NAME		STDOFF	RULES	FORMAT	[UNTIL]
 Zone	EST		 -5:00	-	EST
 Zone	MST		 -7:00	-	MST
 Zone	HST		-10:00	-	HST
@@ -353,7 +376,7 @@
 Rule	NYC	1921	1966	-	Apr	lastSun	2:00	1:00	D
 Rule	NYC	1921	1954	-	Sep	lastSun	2:00	0	S
 Rule	NYC	1955	1966	-	Oct	lastSun	2:00	0	S
-# Zone	NAME		GMTOFF	RULES	FORMAT	[UNTIL]
+# Zone	NAME		STDOFF	RULES	FORMAT	[UNTIL]
 Zone America/New_York	-4:56:02 -	LMT	1883 Nov 18 12:03:58
 			-5:00	US	E%sT	1920
 			-5:00	NYC	E%sT	1942
@@ -413,7 +436,7 @@
 Rule	Chicago	1922	1966	-	Apr	lastSun	2:00	1:00	D
 Rule	Chicago	1922	1954	-	Sep	lastSun	2:00	0	S
 Rule	Chicago	1955	1966	-	Oct	lastSun	2:00	0	S
-# Zone	NAME		GMTOFF	RULES	FORMAT	[UNTIL]
+# Zone	NAME		STDOFF	RULES	FORMAT	[UNTIL]
 Zone America/Chicago	-5:50:36 -	LMT	1883 Nov 18 12:09:24
 			-6:00	US	C%sT	1920
 			-6:00	Chicago	C%sT	1936 Mar  1  2:00
@@ -481,7 +504,7 @@
 Rule	Denver	1921	only	-	May	22	2:00	0	S
 Rule	Denver	1965	1966	-	Apr	lastSun	2:00	1:00	D
 Rule	Denver	1965	1966	-	Oct	lastSun	2:00	0	S
-# Zone	NAME		GMTOFF	RULES	FORMAT	[UNTIL]
+# Zone	NAME		STDOFF	RULES	FORMAT	[UNTIL]
 Zone America/Denver	-6:59:56 -	LMT	1883 Nov 18 12:00:04
 			-7:00	US	M%sT	1920
 			-7:00	Denver	M%sT	1942
@@ -534,7 +557,7 @@
 Rule	CA	1950	1966	-	Apr	lastSun	1:00	1:00	D
 Rule	CA	1950	1961	-	Sep	lastSun	2:00	0	S
 Rule	CA	1962	1966	-	Oct	lastSun	2:00	0	S
-# Zone	NAME		GMTOFF	RULES	FORMAT	[UNTIL]
+# Zone	NAME		STDOFF	RULES	FORMAT	[UNTIL]
 Zone America/Los_Angeles -7:52:58 -	LMT	1883 Nov 18 12:07:02
 			-8:00	US	P%sT	1946
 			-8:00	CA	P%sT	1967
@@ -642,7 +665,7 @@
 # So they won't be waiting for Alaska to join them on 2019-03-10, but will
 # rather change their clocks twice in seven weeks.

-# Zone	NAME		GMTOFF	RULES	FORMAT	[UNTIL]
+# Zone	NAME		STDOFF	RULES	FORMAT	[UNTIL]
 Zone America/Juneau	 15:02:19 -	LMT	1867 Oct 19 15:33:32
 			 -8:57:41 -	LMT	1900 Aug 20 12:00
 			 -8:00	-	PST	1942
@@ -762,7 +785,7 @@
 # Note that 1933-05-21 was a Sunday.
 # We're left to guess the time of day when Act 163 was approved; guess noon.

-# Zone	NAME		GMTOFF	RULES	FORMAT	[UNTIL]
+# Zone	NAME		STDOFF	RULES	FORMAT	[UNTIL]
 Zone Pacific/Honolulu	-10:31:26 -	LMT	1896 Jan 13 12:00
 			-10:30	-	HST	1933 Apr 30  2:00
 			-10:30	1:00	HDT	1933 May 21 12:00
@@ -792,7 +815,7 @@
 # Shanks says the 1944 experiment came to an end on 1944-03-17.
 # Go with the Arizona State Library instead.

-# Zone	NAME		GMTOFF	RULES	FORMAT	[UNTIL]
+# Zone	NAME		STDOFF	RULES	FORMAT	[UNTIL]
 Zone America/Phoenix	-7:28:18 -	LMT	1883 Nov 18 11:31:42
 			-7:00	US	M%sT	1944 Jan  1  0:01
 			-7:00	-	MST	1944 Apr  1  0:01
@@ -818,7 +841,7 @@
 # quarter of Idaho county) and eastern Oregon (most of Malheur County)
 # switched four weeks late in 19