--- contrib/tzdata/Makefile.orig
+++ contrib/tzdata/Makefile
@@ -42,37 +42,64 @@
 # Also see TZDEFRULESTRING below, which takes effect only
 # if the time zone files cannot be accessed.
 
-# Everything gets put in subdirectories of. . .
 
-TOPDIR=		/usr/local
+# Installation locations.
+#
+# The defaults are suitable for Debian, except that if REDO is
+# posix_right or right_posix then files that Debian puts under
+# /usr/share/zoneinfo/posix and /usr/share/zoneinfo/right are instead
+# put under /usr/share/zoneinfo-posix and /usr/share/zoneinfo-leaps,
+# respectively.  Problems with the Debian approach are discussed in
+# the commentary for the right_posix rule (below).
 
+# Destination directory, which can be used for staging.
+# 'make DESTDIR=/stage install' installs under /stage (e.g., to
+# /stage/etc/localtime instead of to /etc/localtime).  Files under
+# /stage are not intended to work as-is, but can be copied by hand to
+# the root directory later.  If DESTDIR is empty, 'make install' does
+# not stage, but installs directly into production locations.
+DESTDIR =
+
+# Everything is installed into subdirectories of TOPDIR, and used there.
+# TOPDIR should be empty (meaning the root directory),
+# or a directory name that does not end in "/".
+# TOPDIR should be empty or an absolute name unless you're just testing.
+TOPDIR =
+
+# The default local time zone is taken from the file TZDEFAULT.
+TZDEFAULT = $(TOPDIR)/etc/localtime
+
+# The subdirectory containing installed program and data files, and
+# likewise for installed files that can be shared among architectures.
+# These should be relative file names.
+USRDIR = usr
+USRSHAREDIR = $(USRDIR)/share
+
 # "Compiled" time zone information is placed in the "TZDIR" directory
 # (and subdirectories).
-# Use an absolute path name for TZDIR unless you're just testing the software.
 # TZDIR_BASENAME should not contain "/" and should not be ".", ".." or empty.
-
 TZDIR_BASENAME=	zoneinfo
-TZDIR=		$(TOPDIR)/etc/$(TZDIR_BASENAME)
+TZDIR = $(TOPDIR)/$(USRSHAREDIR)/$(TZDIR_BASENAME)
 
-# Types to try, as an alternative to time_t.  int64_t should be first.
-TIME_T_ALTERNATIVES= int64_t int32_t uint32_t uint64_t
+# The "tzselect" and (if you do "make INSTALL") "date" commands go in:
+BINDIR = $(TOPDIR)/$(USRDIR)/bin
 
-# The "tzselect", "zic", and "zdump" commands get installed in. . .
+# The "zdump" command goes in:
+ZDUMPDIR = $(BINDIR)
 
-ETCDIR=		$(TOPDIR)/etc
+# The "zic" command goes in:
+ZICDIR = $(TOPDIR)/$(USRDIR)/sbin
 
-# If you "make INSTALL", the "date" command gets installed in. . .
-
-BINDIR=		$(TOPDIR)/bin
-
 # Manual pages go in subdirectories of. . .
+MANDIR = $(TOPDIR)/$(USRSHAREDIR)/man
 
-MANDIR=		$(TOPDIR)/man
-
 # Library functions are put in an archive in LIBDIR.
+LIBDIR = $(TOPDIR)/$(USRDIR)/lib
 
-LIBDIR=		$(TOPDIR)/lib
 
+# Types to try, as an alternative to time_t.  int64_t should be first.
+TIME_T_ALTERNATIVES = int64_t int32_t uint32_t uint64_t
+
 # If you want only POSIX time, with time values interpreted as
 # seconds since the epoch (not counting leap seconds), use
 #	REDO=		posix_only
@@ -105,11 +132,14 @@
 TZDATA_TEXT=	leapseconds tzdata.zi
 
 # For backward-compatibility links for old zone names, use
+#	BACKWARD=	backward
+# If you also want the link US/Pacific-New, even though it is confusing
+# and is planned to be removed from the database eventually, use
 #	BACKWARD=	backward pacificnew
 # To omit these links, use
 #	BACKWARD=
 
-BACKWARD=	backward pacificnew
+BACKWARD=	backward
 
 # If you want out-of-scope and often-wrong data from the file 'backzone', use
 #	PACKRATDATA=	backzone
@@ -313,7 +343,7 @@
 
 # How to use zic to install tz binary files.
 
-ZIC_INSTALL=	$(ZIC) -d $(DESTDIR)$(TZDIR) $(LEAPSECONDS)
+ZIC_INSTALL=	$(ZIC) -d '$(DESTDIR)$(TZDIR)' $(LEAPSECONDS)
 
 # The name of a Posix-compliant 'awk' on your system.
 AWK=		awk
@@ -341,8 +371,8 @@
 VALIDATE = nsgmls
 VALIDATE_FLAGS = -s -B -wall -wno-unused-param
 VALIDATE_ENV = \
-  SGML_CATALOG_FILES=$(SGML_CATALOG_FILES) \
-  SGML_SEARCH_PATH=$(SGML_SEARCH_PATH) \
+  SGML_CATALOG_FILES='$(SGML_CATALOG_FILES)' \
+  SGML_SEARCH_PATH='$(SGML_SEARCH_PATH)' \
   SP_CHARSET_FIXED=YES \
   SP_ENCODING=UTF-8
 
@@ -396,7 +426,7 @@
 #MAKE=		make
 
 cc=		cc
-CC=		$(cc) -DTZDIR=\"$(TZDIR)\"
+CC=		$(cc) -DTZDIR='"$(TZDIR)"'
 
 AR=		ar
 
@@ -421,18 +451,19 @@
 			date.1.txt
 COMMON=		calendars CONTRIBUTING LICENSE Makefile \
 			NEWS README theory.html version
-WEB_PAGES=	tz-art.htm tz-how-to.html tz-link.htm
+WEB_PAGES=	tz-art.html tz-how-to.html tz-link.html
 DOCS=		$(MANS) date.1 $(MANTXTS) $(WEB_PAGES)
 PRIMARY_YDATA=	africa antarctica asia australasia \
 		europe northamerica southamerica
-YDATA=		$(PRIMARY_YDATA) etcetera $(BACKWARD)
+YDATA=		$(PRIMARY_YDATA) etcetera
 NDATA=		systemv factory
-TDATA=		$(YDATA) $(NDATA)
+TDATA_TO_CHECK=	$(YDATA) $(NDATA) backward pacificnew
+TDATA=		$(YDATA) $(NDATA) $(BACKWARD)
 ZONETABLES=	zone1970.tab zone.tab
 TABDATA=	iso3166.tab $(TZDATA_TEXT) $(ZONETABLES)
 LEAP_DEPS=	leapseconds.awk leap-seconds.list
-TZDATA_ZI_DEPS=	zishrink.awk $(TDATA) $(PACKRATDATA)
-DATA=		$(YDATA) $(NDATA) backzone iso3166.tab leap-seconds.list \
+TZDATA_ZI_DEPS=	zishrink.awk version $(TDATA) $(PACKRATDATA)
+DATA=		$(TDATA_TO_CHECK) backzone iso3166.tab leap-seconds.list \
 			leapseconds yearistype.sh $(ZONETABLES)
 AWK_SCRIPTS=	checklinks.awk checktab.awk leapseconds.awk zishrink.awk
 MISC=		$(AWK_SCRIPTS) zoneinfo2tdf.pl
@@ -457,7 +488,7 @@
 		newctime.3 newstrftime.3 newtzset.3 northamerica \
 		pacificnew private.h \
 		southamerica strftime.c systemv theory.html \
-		time2posix.3 tz-art.htm tz-how-to.html tz-link.htm \
+		time2posix.3 tz-art.html tz-how-to.html tz-link.html \
 		tzfile.5 tzfile.h tzselect.8 tzselect.ksh \
 		workman.sh yearistype.sh \
 		zdump.8 zdump.c zic.8 zic.c \
@@ -473,35 +504,41 @@
 ALL:		all date $(ENCHILADA)
 
 install:	all $(DATA) $(REDO) $(MANS)
-		mkdir -p $(DESTDIR)$(ETCDIR) $(DESTDIR)$(TZDIR) \
-			$(DESTDIR)$(LIBDIR) \
-			$(DESTDIR)$(MANDIR)/man3 $(DESTDIR)$(MANDIR)/man5 \
-			$(DESTDIR)$(MANDIR)/man8
-		$(ZIC_INSTALL) -l $(LOCALTIME) -p $(POSIXRULES)
-		cp -f $(TABDATA) $(DESTDIR)$(TZDIR)/.
-		cp tzselect zic zdump $(DESTDIR)$(ETCDIR)/.
-		cp libtz.a $(DESTDIR)$(LIBDIR)/.
-		$(RANLIB) $(DESTDIR)$(LIBDIR)/libtz.a
-		cp -f newctime.3 newtzset.3 $(DESTDIR)$(MANDIR)/man3/.
-		cp -f tzfile.5 $(DESTDIR)$(MANDIR)/man5/.
-		cp -f tzselect.8 zdump.8 zic.8 $(DESTDIR)$(MANDIR)/man8/.
+		mkdir -p '$(DESTDIR)$(BINDIR)' \
+			'$(DESTDIR)$(ZDUMPDIR)' '$(DESTDIR)$(ZICDIR)' \
+			'$(DESTDIR)$(LIBDIR)' \
+			'$(DESTDIR)$(MANDIR)/man3' '$(DESTDIR)$(MANDIR)/man5' \
+			'$(DESTDIR)$(MANDIR)/man8'
+		$(ZIC_INSTALL) -l $(LOCALTIME) -p $(POSIXRULES) \
+			-t '$(DESTDIR)$(TZDEFAULT)'
+		cp -f $(TABDATA) '$(DESTDIR)$(TZDIR)/.'
+		cp tzselect '$(DESTDIR)$(BINDIR)/.'
+		cp zdump '$(DESTDIR)$(ZDUMPDIR)/.'
+		cp zic '$(DESTDIR)$(ZICDIR)/.'
+		cp libtz.a '$(DESTDIR)$(LIBDIR)/.'
+		$(RANLIB) '$(DESTDIR)$(LIBDIR)/libtz.a'
+		cp -f newctime.3 newtzset.3 '$(DESTDIR)$(MANDIR)/man3/.'
+		cp -f tzfile.5 '$(DESTDIR)$(MANDIR)/man5/.'
+		cp -f tzselect.8 zdump.8 zic.8 '$(DESTDIR)$(MANDIR)/man8/.'
 
 INSTALL:	ALL install date.1
-		mkdir -p $(DESTDIR)$(BINDIR) $(DESTDIR)$(MANDIR)/man1
-		cp date $(DESTDIR)$(BINDIR)/.
-		cp -f date.1 $(DESTDIR)$(MANDIR)/man1/.
+		mkdir -p '$(DESTDIR)$(BINDIR)' '$(DESTDIR)$(MANDIR)/man1'
+		cp date '$(DESTDIR)$(BINDIR)/.'
+		cp -f date.1 '$(DESTDIR)$(MANDIR)/man1/.'
 
 version:	$(VERSION_DEPS)
 		{ (type git) >/dev/null 2>&1 && \
 		  V=`git describe --match '[0-9][0-9][0-9][0-9][a-z]*' \
 				--abbrev=7 --dirty` || \
-		  V=$(VERSION); } && \
+		  V='$(VERSION)'; } && \
 		printf '%s\n' "$$V" >$@.out
 		mv $@.out $@
 
 # This file can be tailored by setting BACKWARD, PACKRATDATA, etc.
 tzdata.zi:	$(TZDATA_ZI_DEPS)
-		LC_ALL=C $(AWK) -f zishrink.awk $(TDATA) $(PACKRATDATA) >$@.out
+		version=`sed 1q version` && \
+		  LC_ALL=C $(AWK) -v version="$$version" -f zishrink.awk \
+		    $(TDATA) $(PACKRATDATA) >$@.out
 		mv $@.out $@
 
 version.h:	version
@@ -529,12 +566,13 @@
 # Arguments to pass to submakes of install_data.
 # They can be overridden by later submake arguments.
 INSTALLARGS = \
- BACKWARD=$(BACKWARD) \
- DESTDIR=$(DESTDIR) \
+ BACKWARD='$(BACKWARD)' \
+ DESTDIR='$(DESTDIR)' \
  LEAPSECONDS='$(LEAPSECONDS)' \
  PACKRATDATA='$(PACKRATDATA)' \
- TZDIR=$(TZDIR) \
- YEARISTYPE=$(YEARISTYPE) \
+ TZDEFAULT='$(TZDEFAULT)' \
+ TZDIR='$(TZDIR)' \
+ YEARISTYPE='$(YEARISTYPE)' \
  ZIC='$(ZIC)'
 
 # 'make install_data' installs one set of tz binary files.
@@ -558,16 +596,16 @@
 # You must replace all of $(TZDIR) to switch from not using leap seconds
 # to using them, or vice versa.
 right_posix:	right_only
-		rm -fr $(DESTDIR)$(TZDIR)-leaps
-		ln -s $(TZDIR_BASENAME) $(DESTDIR)$(TZDIR)-leaps || \
-		  $(MAKE) $(INSTALLARGS) TZDIR=$(TZDIR)-leaps right_only
-		$(MAKE) $(INSTALLARGS) TZDIR=$(TZDIR)-posix posix_only
+		rm -fr '$(DESTDIR)$(TZDIR)-leaps'
+		ln -s '$(TZDIR_BASENAME)' '$(DESTDIR)$(TZDIR)-leaps' || \
+		  $(MAKE) $(INSTALLARGS) TZDIR='$(TZDIR)-leaps' right_only
+		$(MAKE) $(INSTALLARGS) TZDIR='$(TZDIR)-posix' posix_only
 
 posix_right:	posix_only
-		rm -fr $(DESTDIR)$(TZDIR)-posix
-		ln -s $(TZDIR_BASENAME) $(DESTDIR)$(TZDIR)-posix || \
-		  $(MAKE) $(INSTALLARGS) TZDIR=$(TZDIR)-posix posix_only
-		$(MAKE) $(INSTALLARGS) TZDIR=$(TZDIR)-leaps right_only
+		rm -fr '$(DESTDIR)$(TZDIR)-posix'
+		ln -s '$(TZDIR_BASENAME)' '$(DESTDIR)$(TZDIR)-posix' || \
+		  $(MAKE) $(INSTALLARGS) TZDIR='$(TZDIR)-posix' posix_only
+		$(MAKE) $(INSTALLARGS) TZDIR='$(TZDIR)-leaps' right_only
 
 # This obsolescent rule is present for backwards compatibility with
 # tz releases 2014g through 2015g.  It should go away eventually.
@@ -633,7 +671,7 @@
 			$(MISC) $(SOURCES) $(WEB_PAGES) \
 			CONTRIBUTING LICENSE Makefile README \
 			version tzdata.zi && \
-		! grep -Env $(SAFE_SHARP_LINE) $(TDATA) backzone \
+		! grep -Env $(SAFE_SHARP_LINE) $(TDATA_TO_CHECK) backzone \
 			leapseconds yearistype.sh zone.tab && \
 		! grep -Env $(OK_LINE) $(ENCHILADA); \
 	}
@@ -641,14 +679,16 @@
 check_white_space: $(ENCHILADA)
 		patfmt=' \t|[\f\r\v]' && pat=`printf "$$patfmt\\n"` && \
 		! grep -En "$$pat" $(ENCHILADA)
-		! grep -n '[[:space:]]$$' $(ENCHILADA)
+		! grep -n '[[:space:]]$$' \
+			$$(ls $(ENCHILADA) | grep -Fvx leap-seconds.list)
 
 PRECEDES_FILE_NAME = ^(Zone|Link[[:space:]]+[^[:space:]]+)[[:space:]]+
 FILE_NAME_COMPONENT_TOO_LONG = \
   $(PRECEDES_FILE_NAME)[^[:space:]]*[^/[:space:]]{15}
 
-check_name_lengths: $(TDATA) backzone
-		! grep -En '$(FILE_NAME_COMPONENT_TOO_LONG)' $(TDATA) backzone
+check_name_lengths: $(TDATA_TO_CHECK) backzone
+		! grep -En '$(FILE_NAME_COMPONENT_TOO_LONG)' \
+			$(TDATA_TO_CHECK) backzone
 
 CHECK_CC_LIST = { n = split($$1,a,/,/); for (i=2; i<=n; i++) print a[1], a[i]; }
 
@@ -662,8 +702,8 @@
 		$(AWK) '/^[^#]/ $(CHECK_CC_LIST)' zone1970.tab | \
 		  LC_ALL=C sort -cu
 
-check_links:	checklinks.awk $(TDATA)
-		$(AWK) -f checklinks.awk $(TDATA)
+check_links:	checklinks.awk $(TDATA_TO_CHECK)
+		$(AWK) -f checklinks.awk $(TDATA_TO_CHECK)
 		$(AWK) -f checklinks.awk tzdata.zi
 
 check_tables:	checktab.awk $(PRIMARY_YDATA) $(ZONETABLES)
@@ -764,12 +804,12 @@
 
 check_public:
 		$(MAKE) maintainer-clean
-		$(MAKE) "CFLAGS=$(GCC_DEBUG_FLAGS)" ALL
+		$(MAKE) CFLAGS='$(GCC_DEBUG_FLAGS)' ALL
 		mkdir -p public.dir
-		for i in $(TDATA) tzdata.zi; do \
+		for i in $(TDATA_TO_CHECK) tzdata.zi; do \
 		  $(zic) -v -d public.dir $$i 2>&1 || exit; \
 		done
-		$(zic) -v -d public.dir $(TDATA)
+		$(zic) -v -d public.dir $(TDATA_TO_CHECK)
 		rm -fr public.dir
 
 # Check that the code works under various alternative
@@ -790,8 +830,11 @@
 		    REDO='$(REDO)' \
 		    install && \
 		  diff $$quiet_option -r \
-		    time_t.dir/int64_t/etc/zoneinfo \
-		    time_t.dir/$$type/etc/zoneinfo && \
+		    time_t.dir/int64_t/etc \
+		    time_t.dir/$$type/etc && \
+		  diff $$quiet_option -r \
+		    time_t.dir/int64_t/usr/share \
+		    time_t.dir/$$type/usr/share && \
 		  case $$type in \
 		  int32_t) range=-2147483648,2147483647;; \
 		  uint32_t) range=0,4294967296;; \
@@ -800,9 +843,9 @@
 		  *) range=-10000000000,10000000000;; \
 		  esac && \
 		  echo checking $$type zones ... && \
-		  time_t.dir/int64_t/etc/zdump -V -t $$range $$zones \
+		  time_t.dir/int64_t/usr/bin/zdump -V -t $$range $$zones \
 		      >time_t.dir/int64_t.out && \
-		  time_t.dir/$$type/etc/zdump -V -t $$range $$zones \
+		  time_t.dir/$$type/usr/bin/zdump -V -t $$range $$zones \
 		      >time_t.dir/$$type.out && \
 		  diff -u time_t.dir/int64_t.out time_t.dir/$$type.out \
 		    || exit; \
--- contrib/tzdata/NEWS.orig
+++ contrib/tzdata/NEWS
@@ -1,5 +1,147 @@
 News for the tz database
 
+Release 2018c - 2018-01-22 23:00:44 -0800
+
+  Briefly:
+  Revert Irish changes that relied on negative DST offsets.
+
+  Changes to tm_isdst
+
+    Revert the 2018a change to Europe/Dublin.  As before, this change
+    does not affect UT offsets or abbreviations; it affects only
+    whether timestamps are considered to be standard time or
+    daylight-saving time, as expressed in the tm_isdst flag of C's
+    struct tm type.  This reversion is intended to be a temporary
+    workaround for problems discovered with downstream uses of
+    releases 2018a and 2018b, which implemented Irish time by using
+    negative DST offsets in the Eire rules of the 'europe' file.
+    Although negative DST offsets have been part of tzcode for many
+    years and are supported by many platforms, they were not
+    documented before 2018a and ICU and OpenJDK do not currently
+    support them.  A mechanism to export data to platforms lacking
+    support for negative DST is planned to be developed before the
+    change is reapplied.  (Problems reported by Deborah Goldsmith and
+    Stephen Colebourne.)
+
+  Changes to past time stamps
+
+    Japanese DST transitions (1948-1951) were Sundays at 00:00, not
+    Saturdays or Sundays at 02:00.  (Thanks to Takayuki Nikai.)
+
+  Changes to build procedure
+
+    The build procedure now works around mawk 1.3.3's lack of support
+    for character class expressions.  (Problem reported by Ohyama.)
+
+
+Release 2018b - 2018-01-17 23:24:48 -0800
+
+  Briefly:
+  Fix a packaging problem in tz2018a, which was missing 'pacificnew'.
+
+  Changes to build procedure
+
+    The distribution now contains the file 'pacificnew' again.
+    This file was inadvertantly omitted in the 2018a distribution.
+    (Problem reported by Matias Fonzo.)
+
+
+Release 2018a - 2018-01-12 22:29:21 -0800
+
+  Briefly:
+  São Tomé and Príncipe switched from +00 to +01.
+  Brazil's DST will now start on November's first Sunday.
+  Ireland's standard time is now in the summer, not the winter.
+  Use Debian-style installation locations, instead of 4.3BSD-style.
+  New zic option -t.
+
+  Changes to past and future time stamps
+
+    São Tomé and Príncipe switched from +00 to +01 on 2018-01-01 at
+    01:00.  (Thanks to Steffen Thorsen and Michael Deckers.)
+
+  Changes to future time stamps
+
+    Starting in 2018 southern Brazil will begin DST on November's
+    first Sunday instead of October's third Sunday.  (Thanks to
+    Steffen Thorsen.)
+
+  Changes to past time stamps
+
+    A discrepancy of 4 s in timestamps before 1931 in South Sudan has
+    been corrected.  The 'backzone' and 'zone.tab' files did not agree
+    with the 'africa' and 'zone1970.tab' files.  (Problem reported by
+    Michael Deckers.)
+
+    The abbreviation invented for Bolivia Summer Time (1931-2) is now
+    BST instead of BOST, to be more consistent with the convention
+    used for Latvian Summer Time (1918-9) and for British Summer Time.
+
+  Changes to tm_isdst
+
+    Change Europe/Dublin so that it observes Irish Standard Time (UT
+    +01) in summer and GMT (as negative daylight-saving) in winter,
+    instead of observing standard time (GMT) in winter and Irish
+    Summer Time (UT +01) in summer.  This change does not affect UT
+    offsets or abbreviations; it affects only whether timestamps are
+    considered to be standard time or daylight-saving time, as
+    expressed in the tm_isdst flag of C's struct tm type.
+    (Discrepancy noted by Derick Rethans.)
+
+  Changes to build procedure
+
+    The default installation locations have been changed to mostly
+    match Debian circa 2017, instead of being designed as an add-on to
+    4.3BSD circa 1986.  This affects the Makefile macros TOPDIR,
+    TZDIR, MANDIR, and LIBDIR.  New Makefile macros TZDEFAULT, USRDIR,
+    USRSHAREDIR, BINDIR, ZDUMPDIR, and ZICDIR let installers tailor
+    locations more precisely.  (This responds to suggestions from
+    Brian Inglis and from Steve Summit.)
+
+    The default installation procedure no longer creates the
+    backward-compatibility link US/Pacific-New, which causes
+    confusion during user setup (e.g., see Debian bug 815200).
+    Use 'make BACKWARD="backward pacificnew"' to create the link
+    anyway, for now.  Eventually we plan to remove the link entirely.
+
+    tzdata.zi now contains a version-number comment.
+    (Suggested by Tom Lane.)
+
+    The Makefile now quotes values like BACKWARD more carefully when
+    passing them to the shell.  (Problem reported by Zefram.)
+
+    Builders no longer need to specify -DHAVE_SNPRINTF on platforms
+    that have snprintf and use pre-C99 compilers.  (Problem reported
+    by Jon Skeet.)
+
+  Changes to code
+
+    zic has a new option -t FILE that specifies the location of the
+    file that determines local time when TZ is unset.  The default for
+    this location can be configured via the new TZDEFAULT makefile
+    macro, which defaults to /etc/localtime.
+
+    Diagnostics and commentary now distinguish UT from UTC more
+    carefully; see theory.html for more information about UT vs UTC.
+
+    zic has been ported to GCC 8's -Wstringop-truncation option.
+    (Problem reported by Martin Sebor.)
+
+  Changes to documentation and commentary
+
+    The zic man page now documents the longstanding behavior that
+    times and years can be out of the usual range, with negative times
+    counting backwards from midnight and with year 0 preceding year 1.
+    (Problem reported by Michael Deckers.)
+
+    The theory.html file now mentions the POSIX limit of six chars
+    per abbreviation, and lists alphabetic abbreviations used.
+
+    The files tz-art.htm and tz-link.htm have been renamed to
+    tz-art.html and tz-link.html, respectively, for consistency with
+    other file names and to simplify web server configuration.
+
+
 Release 2017c - 2017-10-20 14:49:34 -0700
 
   Briefly:
@@ -895,8 +1037,8 @@
     (Thanks to Jon Skeet and Arthur David Olson.)  Constraints on
     simultaneity are now documented.
 
-    The two characters '%z' in a zone format now stand for the UTC
-    offset, e.g., '-07' for seven hours behind UTC and '+0530' for
+    The two characters '%z' in a zone format now stand for the UT
+    offset, e.g., '-07' for seven hours behind UT and '+0530' for
     five hours and thirty minutes ahead.  This better supports time
     zone abbreviations conforming to POSIX.1-2001 and later.
 
@@ -1019,13 +1161,13 @@
       The spring 1988 transition was 1988-10-09, not 1988-10-02.
       The fall 1990 transition was 1990-03-11, not 1990-03-18.
 
-      Assume no UTC offset change for Pacific/Easter on 1890-01-01,
+      Assume no UT offset change for Pacific/Easter on 1890-01-01,
       and omit all transitions on Pacific/Easter from 1942 through 1946
       since we have no data suggesting that they existed.
 
     One more zone has been turned into a link, as it differed
     from an existing zone only for older time stamps.  As usual,
-    this change affects UTC offsets in pre-1970 time stamps only.
+    this change affects UT offsets in pre-1970 time stamps only.
     The zone's old contents have been moved to the 'backzone' file.
     The affected zone is America/Montreal.
 
@@ -1055,7 +1197,7 @@
 
     Some more zones have been turned into links, when they differed
     from existing zones only for older time stamps.  As usual,
-    these changes affect UTC offsets in pre-1970 time stamps only.
+    these changes affect UT offsets in pre-1970 time stamps only.
     Their old contents have been moved to the 'backzone' file.
     The affected zones are: America/Antigua, America/Cayman,
     Pacific/Midway, and Pacific/Saipan.
@@ -1107,7 +1249,7 @@
 
     Some more zones have been turned into links, when they differed
     from existing zones only for older time stamps.  As usual,
-    these changes affect UTC offsets in pre-1970 time stamps only.
+    these changes affect UT offsets in pre-1970 time stamps only.
     Their old contents have been moved to the 'backzone' file.
     The affected zones are: Asia/Aden, Asia/Bahrain, Asia/Kuwait,
     and Asia/Muscat.
@@ -1154,7 +1296,7 @@
 
     Some more zones have been turned into links, when they differed
     from existing zones only for older time stamps.  As usual,
-    these changes affect UTC offsets in pre-1970 time stamps only.
+    these changes affect UT offsets in pre-1970 time stamps only.
     Their old contents have been moved to the 'backzone' file.
     The affected zones are: Africa/Addis_Ababa, Africa/Asmara,
     Africa/Dar_es_Salaam, Africa/Djibouti, Africa/Kampala,
@@ -1244,7 +1386,7 @@
 
     Some more zones have been turned into links, when they differed
     from existing zones only for older timestamps.  As usual,
-    these changes affect UTC offsets in pre-1970 timestamps only.
+    these changes affect UT offsets in pre-1970 timestamps only.
     Their old contents have been moved to the 'backzone' file.
     The affected zones are: Africa/Blantyre, Africa/Bujumbura,
     Africa/Gaborone, Africa/Harare, Africa/Kigali, Africa/Lubumbashi,
@@ -1329,7 +1471,7 @@
 
     Some more zones have been turned into links, when they differed
     from existing zones only for older timestamps.  As usual,
-    these changes affect UTC offsets in pre-1970 timestamps only.
+    these changes affect UT offsets in pre-1970 timestamps only.
     Their old contents have been moved to the 'backzone' file.
     The affected zones are: Africa/Bangui, Africa/Brazzaville,
     Africa/Douala, Africa/Kinshasa, Africa/Libreville, Africa/Luanda,
@@ -1479,7 +1621,7 @@
     standard and daylight saving time the abbreviations are AEST and AEDT
     instead of the former EST for both; similarly, ACST/ACDT, ACWST/ACWDT,
     and AWST/AWDT are now used instead of the former CST, CWST, and WST.
-    This change does not affect UTC offsets, only time zone abbreviations.
+    This change does not affect UT offsets, only time zone abbreviations.
     (Thanks to Rich Tibbett and many others.)
 
     Asia/Novokuznetsk shifts from NOVT to KRAT (remaining on UT +07)
@@ -1516,8 +1658,8 @@
     Treindl sent helpful translations of two papers by Guo Qingsheng.)
 
     Some zones have been turned into links, when they differed from existing
-    zones only for older UTC offsets where data entries were likely invented.
-    These changes affect UTC offsets in pre-1970 timestamps only.  This is
+    zones only for older UT offsets where data entries were likely invented.
+    These changes affect UT offsets in pre-1970 timestamps only.  This is
     similar to the change in release 2013e, except this time for western
     Africa.  The affected zones are: Africa/Bamako, Africa/Banjul,
     Africa/Conakry, Africa/Dakar, Africa/Freetown, Africa/Lome,
--- contrib/tzdata/README.orig
+++ contrib/tzdata/README
@@ -11,7 +11,7 @@
 and daylight-saving rules.
 
 See backzone that is distributed along
+with the database proper, this file is less reliable and does not
+necessarily follow database guidelines.
 
@@ -240,7 +244,7 @@
 zone rules.  It is intended to be an exhaustive list of names for
 geographic regions as described above; this is a subset of the names
 in the data.  Although a 'zone1970.tab' location's longitude
-corresponds to its LMT offset with one hour for every 15 degrees east
+corresponds to its LMT offset with one hour for every 15° east
 longitude, this relationship is not exact.
 
+' or '-'.
 		Previous editions of this database also used characters like
 		' ' and '?', but these
@@ -297,7 +301,7 @@
 		'+' and '-' are safe in all locales.
 
 		In other words, in the C locale the POSIX extended regular
-		expression [-+[:alnum:]]{3,} should match
+		expression [-+[:alnum:]]{3,6} should match
 		the abbreviation.
 		This guarantees that all abbreviations could have been
 		specified by a POSIX TZ string.
@@ -308,12 +312,96 @@
 		We assume that applications translate them to other languages
 		as part of the normal localization process; for example,
 		a French application might translate 'EST' to 'HNE'.
+
+These abbreviations (for standard/daylight/etc. time) are: +ACST/ACDT Australian Central, +AST/ADT/APT/AWT/ADDT Atlantic, +AEST/AEDT Australian Eastern, +AHST/AHDT Alaska-Hawaii, +AKST/AKDT Alaska, +AWST/AWDT Australian Western, +BST/BDT Bering, +CAT/CAST Central Africa, +CET/CEST/CEMT Central European, +ChST Chamorro, +CST/CDT/CWT/CPT/CDDT Central [North America], +CST/CDT China, +GMT/BST/IST/BDST Greenwich, +EAT East Africa, +EST/EDT/EWT/EPT/EDDT Eastern [North America], +EET/EEST Eastern European, +GST Guam, +HST/HDT Hawaii, +HKT/HKST Hong Kong, +IST India, +IST/GMT Irish, +IST/IDT/IDDT Israel, +JST/JDT Japan, +KST/KDT Korea, +MET/MEST Middle European (a backward-compatibility alias for Central European), +MSK/MSD Moscow, +MST/MDT/MWT/MPT/MDDT Mountain, +NST/NDT/NWT/NPT/NDDT Newfoundland, +NST/NDT/NWT/NPT Nome, +NZMT/NZST New Zealand through 1945, +NZST/NZDT New Zealand 1946–present, +PKT/PKST Pakistan, +PST/PDT/PWT/PPT/PDDT Pacific, +SAST South Africa, +SST Samoa, +WAT/WAST West Africa, +WET/WEST/WEMT Western European, +WIB Waktu Indonesia Barat, +WIT Waktu Indonesia Timur, +WITA Waktu Indonesia Tengah, +YST/YDT/YWT/YPT/YDDT Yukon.
-004430' for MMT) would
+cause trouble here, as the numeric strings would exceed the POSIX length limit.
+
+These abbreviations are: +AMT Amsterdam, Asunción, Athens; +BMT Baghdad, Bangkok, Batavia, Bern, Bogotá, Bridgetown, Brussels, Bucharest; +CMT Calamarca, Caracas, Chisinau, Colón, Copenhagen, Córdoba; +DMT Dublin/Dunsink; +EMT Easter; +FFMT Fort-de-France; +FMT Funchal; +GMT Greenwich; +HMT Havana, Helsinki, Horta, Howrah; +IMT Irkutsk, Istanbul; +JMT Jerusalem; +KMT Kaunas, Kiev, Kingston; +LMT Lima, Lisbon, local, Luanda; +MMT Macassar, Madras, Malé, Managua, Minsk, Monrovia, Montevideo, Moratuwa, + Moscow; +PLMT Phù Liễn; +PMT Paramaribo, Paris, Perm, Pontianak, Prague; +PMMT Port Moresby; +QMT Quito; +RMT Rangoon, Riga, Rome; +SDMT Santo Domingo; +SJMT San José; +SMT Santiago, Simferopol, Singapore, Stanley; +TBMT Tbilisi; +TMT Tallinn, Tehran; +WMT Warsaw.
+ +A few abbreviations also follow the pattern that +GMT/BST established for time in the UK. They are: + +CMT/BST for Calamarca Mean Time and Bolivian Summer Time +1890–1932, DMT/IST for Dublin/Dunsink Mean Time and Irish Summer Time +1880–1916, MMT/MST/MDST for Moscow 1880–1919, and RMT/LST +for Riga Mean Time and Latvian Summer time 1880–1926. +An extra-special case is SET for Swedish Time (svensk +normaltid) 1879–1899, 3° west of the Stockholm +Observatory.
%z.
-    They are problematic as they mean tz data entries invent
-    notation rather than record it.  These guidelines are now
-    deprecated and the plan is to gradually move to %z for
-    inhabited locations and to "-00" for uninhabited locations.]
--00') for
 		locations while uninhabited.  The leading
 		'-' is a flag that the time
@@ -376,10 +438,10 @@
 
 Application writers should note that these abbreviations are ambiguous
-in practice: e.g. 'CST' has a different meaning in China than
-it does in the United States.  In new applications, it's often better
-to use numeric UT offsets like '-0600' instead of time zone
-abbreviations like 'CST'; this avoids the ambiguity.
+in practice: e.g., 'CST' means one thing in China and something else
+in North America, and 'IST' can refer to time in India, Ireland or
+Israel. To avoid ambiguity, use numeric UT offsets like
+'-0600' instead of time zone abbreviations like 'CST'.
 
 The tz database is not authoritative, and it surely has errors.
-Corrections are welcome and encouraged; see the file CONTRIBUTING.
+Corrections are welcome and encouraged; see the file CONTRIBUTING.
 Users requiring authoritative data should consult national standards
 bodies and the references cited in the database's comments.
 
<UTC+10>'; this allows
+		in a quoted form like '<+09>'; this allows
 		"+" and "-" in the names.
       
       zic features, so that users can run
 older zic versions to process newer data
-files.  Sources for time zone and daylight
+files.  Sources for time zone and daylight
 saving time data describes how
 releases are tagged and distributed.
 
@@ -1003,7 +1065,7 @@
 Michael Allison and Robert Schmunk,
 "Technical
 Notes on Mars Solar Time as Adopted by the Mars24 Sunclock"
-(2012-08-08).
+(2015-06-30).