Merge tag '20220623.1-1' into bullseye-backports-staging

65 files changed, 424 insertions, 91 deletions

diff --git a/absl/time/internal/cctz/BUILD.bazel b/absl/time/internal/cctz/BUILD.bazel
index 45a95292..7304d40d 100644
--- a/absl/time/internal/cctz/BUILD.bazel
+++ b/absl/time/internal/cctz/BUILD.bazel
@@ -12,8 +12,6 @@
 #   See the License for the specific language governing permissions and
 #   limitations under the License.
 
-load("@rules_cc//cc:defs.bzl", "cc_library", "cc_test")
-
 package(features = ["-parse_headers"])
 
 licenses(["notice"])
@@ -26,14 +24,14 @@ filegroup(
 config_setting(
     name = "osx",
     constraint_values = [
-        "@bazel_tools//platforms:osx",
+        "@platforms//os:osx",
     ],
 )
 
 config_setting(
     name = "ios",
     constraint_values = [
-        "@bazel_tools//platforms:ios",
+        "@platforms//os:ios",
     ],
 )
 
@@ -87,7 +85,11 @@ cc_library(
     deps = [
         ":civil_time",
         "//absl/base:config",
-    ],
+    ] + select(
+        {
+            "//conditions:default": [],
+        },
+    ),
 )
 
 ### tests
@@ -117,6 +119,7 @@ cc_test(
         "no_test_android_arm",
         "no_test_android_arm64",
         "no_test_android_x86",
+        "no_test_wasm",
     ],
     deps = [
         ":civil_time",
@@ -136,6 +139,7 @@ cc_test(
         "no_test_android_arm",
         "no_test_android_arm64",
         "no_test_android_x86",
+        "no_test_wasm",
     ],
     deps = [
         ":civil_time",
diff --git a/absl/time/internal/cctz/include/cctz/civil_time_detail.h b/absl/time/internal/cctz/include/cctz/civil_time_detail.h
index 8aadde57..a5b084e6 100644
--- a/absl/time/internal/cctz/include/cctz/civil_time_detail.h
+++ b/absl/time/internal/cctz/include/cctz/civil_time_detail.h
@@ -84,14 +84,13 @@ CONSTEXPR_F bool is_leap_year(year_t y) noexcept {
   return y % 4 == 0 && (y % 100 != 0 || y % 400 == 0);
 }
 CONSTEXPR_F int year_index(year_t y, month_t m) noexcept {
-  return (static_cast<int>((y + (m > 2)) % 400) + 400) % 400;
+  const int yi = static_cast<int>((y + (m > 2)) % 400);
+  return yi < 0 ? yi + 400 : yi;
 }
-CONSTEXPR_F int days_per_century(year_t y, month_t m) noexcept {
-  const int yi = year_index(y, m);
+CONSTEXPR_F int days_per_century(int yi) noexcept {
   return 36524 + (yi == 0 || yi > 300);
 }
-CONSTEXPR_F int days_per_4years(year_t y, month_t m) noexcept {
-  const int yi = year_index(y, m);
+CONSTEXPR_F int days_per_4years(int yi) noexcept {
   return 1460 + (yi == 0 || yi > 300 || (yi - 1) % 100 < 96);
 }
 CONSTEXPR_F int days_per_year(year_t y, month_t m) noexcept {
@@ -133,17 +132,22 @@ CONSTEXPR_F fields n_day(year_t y, month_t m, diff_t d, diff_t cd, hour_t hh,
     }
   }
   if (d > 365) {
+    int yi = year_index(ey, m);  // Index into Gregorian 400 year cycle.
     for (;;) {
-      int n = days_per_century(ey, m);
+      int n = days_per_century(yi);
       if (d <= n) break;
       d -= n;
       ey += 100;
+      yi += 100;
+      if (yi >= 400) yi -= 400;
     }
     for (;;) {
-      int n = days_per_4years(ey, m);
+      int n = days_per_4years(yi);
       if (d <= n) break;
       d -= n;
       ey += 4;
+      yi += 4;
+      if (yi >= 400) yi -= 400;
     }
     for (;;) {
       int n = days_per_year(ey, m);
diff --git a/absl/time/internal/cctz/include/cctz/time_zone.h b/absl/time/internal/cctz/include/cctz/time_zone.h
index 5562a37b..6e382dc6 100644
--- a/absl/time/internal/cctz/include/cctz/time_zone.h
+++ b/absl/time/internal/cctz/include/cctz/time_zone.h
@@ -22,6 +22,7 @@
 
 #include <chrono>
 #include <cstdint>
+#include <limits>
 #include <string>
 #include <utility>
 
@@ -41,20 +42,9 @@ using sys_seconds = seconds;  // Deprecated.  Use cctz::seconds instead.
 
 namespace detail {
 template <typename D>
-inline std::pair<time_point<seconds>, D> split_seconds(
-    const time_point<D>& tp) {
-  auto sec = std::chrono::time_point_cast<seconds>(tp);
-  auto sub = tp - sec;
-  if (sub.count() < 0) {
-    sec -= seconds(1);
-    sub += seconds(1);
-  }
-  return {sec, std::chrono::duration_cast<D>(sub)};
-}
-inline std::pair<time_point<seconds>, seconds> split_seconds(
-    const time_point<seconds>& tp) {
-  return {tp, seconds::zero()};
-}
+std::pair<time_point<seconds>, D> split_seconds(const time_point<D>& tp);
+std::pair<time_point<seconds>, seconds> split_seconds(
+    const time_point<seconds>& tp);
 }  // namespace detail
 
 // cctz::time_zone is an opaque, small, value-type class representing a
@@ -279,6 +269,20 @@ std::string format(const std::string&, const time_point<seconds>&,
                    const femtoseconds&, const time_zone&);
 bool parse(const std::string&, const std::string&, const time_zone&,
            time_point<seconds>*, femtoseconds*, std::string* err = nullptr);
+template <typename Rep, std::intmax_t Denom>
+bool join_seconds(
+    const time_point<seconds>& sec, const femtoseconds& fs,
+    time_point<std::chrono::duration<Rep, std::ratio<1, Denom>>>* tpp);
+template <typename Rep, std::intmax_t Num>
+bool join_seconds(
+    const time_point<seconds>& sec, const femtoseconds& fs,
+    time_point<std::chrono::duration<Rep, std::ratio<Num, 1>>>* tpp);
+template <typename Rep>
+bool join_seconds(
+    const time_point<seconds>& sec, const femtoseconds& fs,
+    time_point<std::chrono::duration<Rep, std::ratio<1, 1>>>* tpp);
+bool join_seconds(const time_point<seconds>& sec, const femtoseconds&,
+                  time_point<seconds>* tpp);
 }  // namespace detail
 
 // Formats the given time_point in the given cctz::time_zone according to
@@ -369,15 +373,84 @@ inline bool parse(const std::string& fmt, const std::string& input,
                   const time_zone& tz, time_point<D>* tpp) {
   time_point<seconds> sec;
   detail::femtoseconds fs;
-  const bool b = detail::parse(fmt, input, tz, &sec, &fs);
-  if (b) {
-    // TODO: Return false if unrepresentable as a time_point<D>.
-    *tpp = std::chrono::time_point_cast<D>(sec);
-    *tpp += std::chrono::duration_cast<D>(fs);
+  return detail::parse(fmt, input, tz, &sec, &fs) &&
+         detail::join_seconds(sec, fs, tpp);
+}
+
+namespace detail {
+
+// Split a time_point<D> into a time_point<seconds> and a D subseconds.
+// Undefined behavior if time_point<seconds> is not of sufficient range.
+// Note that this means it is UB to call cctz::time_zone::lookup(tp) or
+// cctz::format(fmt, tp, tz) with a time_point that is outside the range
+// of a 64-bit std::time_t.
+template <typename D>
+std::pair<time_point<seconds>, D> split_seconds(const time_point<D>& tp) {
+  auto sec = std::chrono::time_point_cast<seconds>(tp);
+  auto sub = tp - sec;
+  if (sub.count() < 0) {
+    sec -= seconds(1);
+    sub += seconds(1);
   }
-  return b;
+  return {sec, std::chrono::duration_cast<D>(sub)};
+}
+
+inline std::pair<time_point<seconds>, seconds> split_seconds(
+    const time_point<seconds>& tp) {
+  return {tp, seconds::zero()};
 }
 
+// Join a time_point<seconds> and femto subseconds into a time_point<D>.
+// Floors to the resolution of time_point<D>. Returns false if time_point<D>
+// is not of sufficient range.
+template <typename Rep, std::intmax_t Denom>
+bool join_seconds(
+    const time_point<seconds>& sec, const femtoseconds& fs,
+    time_point<std::chrono::duration<Rep, std::ratio<1, Denom>>>* tpp) {
+  using D = std::chrono::duration<Rep, std::ratio<1, Denom>>;
+  // TODO(#199): Return false if result unrepresentable as a time_point<D>.
+  *tpp = std::chrono::time_point_cast<D>(sec);
+  *tpp += std::chrono::duration_cast<D>(fs);
+  return true;
+}
+
+template <typename Rep, std::intmax_t Num>
+bool join_seconds(
+    const time_point<seconds>& sec, const femtoseconds&,
+    time_point<std::chrono::duration<Rep, std::ratio<Num, 1>>>* tpp) {
+  using D = std::chrono::duration<Rep, std::ratio<Num, 1>>;
+  auto count = sec.time_since_epoch().count();
+  if (count >= 0 || count % Num == 0) {
+    count /= Num;
+  } else {
+    count /= Num;
+    count -= 1;
+  }
+  if (count > (std::numeric_limits<Rep>::max)()) return false;
+  if (count < (std::numeric_limits<Rep>::min)()) return false;
+  *tpp = time_point<D>() + D{static_cast<Rep>(count)};
+  return true;
+}
+
+template <typename Rep>
+bool join_seconds(
+    const time_point<seconds>& sec, const femtoseconds&,
+    time_point<std::chrono::duration<Rep, std::ratio<1, 1>>>* tpp) {
+  using D = std::chrono::duration<Rep, std::ratio<1, 1>>;
+  auto count = sec.time_since_epoch().count();
+  if (count > (std::numeric_limits<Rep>::max)()) return false;
+  if (count < (std::numeric_limits<Rep>::min)()) return false;
+  *tpp = time_point<D>() + D{static_cast<Rep>(count)};
+  return true;
+}
+
+inline bool join_seconds(const time_point<seconds>& sec, const femtoseconds&,
+                         time_point<seconds>* tpp) {
+  *tpp = sec;
+  return true;
+}
+
+}  // namespace detail
 }  // namespace cctz
 }  // namespace time_internal
 ABSL_NAMESPACE_END
diff --git a/absl/time/internal/cctz/src/cctz_benchmark.cc b/absl/time/internal/cctz/src/cctz_benchmark.cc
index 4e39188f..6770ad6b 100644
--- a/absl/time/internal/cctz/src/cctz_benchmark.cc
+++ b/absl/time/internal/cctz/src/cctz_benchmark.cc
@@ -648,6 +648,7 @@ const char* const kTimeZoneNames[] = {"Africa/Abidjan",
                                       "Pacific/Guam",
                                       "Pacific/Honolulu",
                                       "Pacific/Johnston",
+                                      "Pacific/Kanton",
                                       "Pacific/Kiritimati",
                                       "Pacific/Kosrae",
                                       "Pacific/Kwajalein",
diff --git a/absl/time/internal/cctz/src/time_zone_fixed.cc b/absl/time/internal/cctz/src/time_zone_fixed.cc
index 303c0244..f2b3294e 100644
--- a/absl/time/internal/cctz/src/time_zone_fixed.cc
+++ b/absl/time/internal/cctz/src/time_zone_fixed.cc
@@ -53,7 +53,7 @@ int Parse02d(const char* p) {
 }  // namespace
 
 bool FixedOffsetFromName(const std::string& name, seconds* offset) {
-  if (name.compare(0, std::string::npos, "UTC", 3) == 0) {
+  if (name == "UTC" || name == "UTC0") {
     *offset = seconds::zero();
     return true;
   }
diff --git a/absl/time/internal/cctz/src/time_zone_format_test.cc b/absl/time/internal/cctz/src/time_zone_format_test.cc
index a11f93e2..f1f79a20 100644
--- a/absl/time/internal/cctz/src/time_zone_format_test.cc
+++ b/absl/time/internal/cctz/src/time_zone_format_test.cc
@@ -13,15 +13,20 @@
 //   limitations under the License.
 
 #include <chrono>
+#include <cstdint>
 #include <iomanip>
 #include <sstream>
 #include <string>
 
+#include "absl/base/config.h"
+#include "absl/time/internal/cctz/include/cctz/time_zone.h"
+#if defined(__linux__)
+#include <features.h>
+#endif
+
 #include "gmock/gmock.h"
 #include "gtest/gtest.h"
-#include "absl/base/config.h"
 #include "absl/time/internal/cctz/include/cctz/civil_time.h"
-#include "absl/time/internal/cctz/include/cctz/time_zone.h"
 
 namespace chrono = std::chrono;
 
@@ -182,8 +187,10 @@ TEST(Format, PosixConversions) {
   TestFormatSpecifier(tp, tz, "%F", "1970-01-01");
   TestFormatSpecifier(tp, tz, "%g", "70");
   TestFormatSpecifier(tp, tz, "%G", "1970");
+#if defined(__GLIBC__)
   TestFormatSpecifier(tp, tz, "%k", " 0");
   TestFormatSpecifier(tp, tz, "%l", "12");
+#endif
   TestFormatSpecifier(tp, tz, "%n", "\n");
   TestFormatSpecifier(tp, tz, "%R", "00:00");
   TestFormatSpecifier(tp, tz, "%t", "\t");
@@ -215,7 +222,9 @@ TEST(Format, LocaleSpecific) {
 #if defined(__linux__)
   // SU/C99/TZ extensions
   TestFormatSpecifier(tp, tz, "%h", "Jan");  // Same as %b
+#if defined(__GLIBC__)
   TestFormatSpecifier(tp, tz, "%P", "am");
+#endif
   TestFormatSpecifier(tp, tz, "%r", "12:00:00 AM");
 
   // Modified conversion specifiers %E_
@@ -1044,9 +1053,11 @@ TEST(Parse, LocaleSpecific) {
   EXPECT_TRUE(parse("%h", "Feb", tz, &tp));
   EXPECT_EQ(2, convert(tp, tz).month());  // Equivalent to %b
 
+#if defined(__GLIBC__)
   tp = reset;
   EXPECT_TRUE(parse("%l %p", "5 PM", tz, &tp));
   EXPECT_EQ(17, convert(tp, tz).hour());
+#endif
 
   tp = reset;
   EXPECT_TRUE(parse("%r", "03:44:55 PM", tz, &tp));
@@ -1054,6 +1065,7 @@ TEST(Parse, LocaleSpecific) {
   EXPECT_EQ(44, convert(tp, tz).minute());
   EXPECT_EQ(55, convert(tp, tz).second());
 
+#if defined(__GLIBC__)
   tp = reset;
   EXPECT_TRUE(parse("%Ec", "Tue Nov 19 05:06:07 2013", tz, &tp));
   EXPECT_EQ(convert(civil_second(2013, 11, 19, 5, 6, 7), tz), tp);
@@ -1125,6 +1137,7 @@ TEST(Parse, LocaleSpecific) {
   EXPECT_TRUE(parse("%Oy", "04", tz, &tp));
   EXPECT_EQ(2004, convert(tp, tz).year());
 #endif
+#endif
 }
 
 TEST(Parse, ExtendedSeconds) {
@@ -1135,7 +1148,7 @@ TEST(Parse, ExtendedSeconds) {
   // All %E<prec>S cases are treated the same as %E*S on input.
   auto precisions = {"*", "0", "1",  "2",  "3",  "4",  "5",  "6", "7",
                      "8", "9", "10", "11", "12", "13", "14", "15"};
-  for (const std::string& prec : precisions) {
+  for (const std::string prec : precisions) {
     const std::string fmt = "%E" + prec + "S";
     SCOPED_TRACE(fmt);
     time_point<chrono::nanoseconds> tp = unix_epoch;
@@ -1217,7 +1230,7 @@ TEST(Parse, ExtendedSubeconds) {
   // All %E<prec>f cases are treated the same as %E*f on input.
   auto precisions = {"*", "0", "1",  "2",  "3",  "4",  "5",  "6", "7",
                      "8", "9", "10", "11", "12", "13", "14", "15"};
-  for (const std::string& prec : precisions) {
+  for (const std::string prec : precisions) {
     const std::string fmt = "%E" + prec + "f";
     SCOPED_TRACE(fmt);
     time_point<chrono::nanoseconds> tp = unix_epoch - chrono::seconds(1);
@@ -1504,7 +1517,7 @@ TEST(Parse, MaxRange) {
       parse(RFC3339_sec, "292277026596-12-04T14:30:07-01:00", utc, &tp));
   EXPECT_EQ(tp, time_point<absl::time_internal::cctz::seconds>::max());
   EXPECT_FALSE(
-      parse(RFC3339_sec, "292277026596-12-04T15:30:07-01:00", utc, &tp));
+      parse(RFC3339_sec, "292277026596-12-04T14:30:08-01:00", utc, &tp));
 
   // tests the lower limit using +00:00 offset
   EXPECT_TRUE(
@@ -1525,10 +1538,82 @@ TEST(Parse, MaxRange) {
       parse(RFC3339_sec, "9223372036854775807-12-31T23:59:59-00:01", utc, &tp));
   EXPECT_FALSE(parse(RFC3339_sec, "-9223372036854775808-01-01T00:00:00+00:01",
                      utc, &tp));
+}
+
+TEST(Parse, TimePointOverflow) {
+  const time_zone utc = utc_time_zone();
+
+  using D = chrono::duration<std::int64_t, std::nano>;
+  time_point<D> tp;
+
+  EXPECT_TRUE(
+      parse(RFC3339_full, "2262-04-11T23:47:16.8547758079+00:00", utc, &tp));
+  EXPECT_EQ(tp, time_point<D>::max());
+  EXPECT_EQ("2262-04-11T23:47:16.854775807+00:00",
+            format(RFC3339_full, tp, utc));
+#if 0
+  // TODO(#199): Will fail until cctz::parse() properly detects overflow.
+  EXPECT_FALSE(
+      parse(RFC3339_full, "2262-04-11T23:47:16.8547758080+00:00", utc, &tp));
+  EXPECT_TRUE(
+      parse(RFC3339_full, "1677-09-21T00:12:43.1452241920+00:00", utc, &tp));
+  EXPECT_EQ(tp, time_point<D>::min());
+  EXPECT_EQ("1677-09-21T00:12:43.145224192+00:00",
+            format(RFC3339_full, tp, utc));
+  EXPECT_FALSE(
+      parse(RFC3339_full, "1677-09-21T00:12:43.1452241919+00:00", utc, &tp));
+#endif
+
+  using DS = chrono::duration<std::int8_t, chrono::seconds::period>;
+  time_point<DS> stp;
+
+  EXPECT_TRUE(parse(RFC3339_full, "1970-01-01T00:02:07.9+00:00", utc, &stp));
+  EXPECT_EQ(stp, time_point<DS>::max());
+  EXPECT_EQ("1970-01-01T00:02:07+00:00", format(RFC3339_full, stp, utc));
+  EXPECT_FALSE(parse(RFC3339_full, "1970-01-01T00:02:08+00:00", utc, &stp));
+
+  EXPECT_TRUE(parse(RFC3339_full, "1969-12-31T23:57:52+00:00", utc, &stp));
+  EXPECT_EQ(stp, time_point<DS>::min());
+  EXPECT_EQ("1969-12-31T23:57:52+00:00", format(RFC3339_full, stp, utc));
+  EXPECT_FALSE(parse(RFC3339_full, "1969-12-31T23:57:51.9+00:00", utc, &stp));
+
+  using DM = chrono::duration<std::int8_t, chrono::minutes::period>;
+  time_point<DM> mtp;
+
+  EXPECT_TRUE(parse(RFC3339_full, "1970-01-01T02:07:59+00:00", utc, &mtp));
+  EXPECT_EQ(mtp, time_point<DM>::max());
+  EXPECT_EQ("1970-01-01T02:07:00+00:00", format(RFC3339_full, mtp, utc));
+  EXPECT_FALSE(parse(RFC3339_full, "1970-01-01T02:08:00+00:00", utc, &mtp));
+
+  EXPECT_TRUE(parse(RFC3339_full, "1969-12-31T21:52:00+00:00", utc, &mtp));
+  EXPECT_EQ(mtp, time_point<DM>::min());
+  EXPECT_EQ("1969-12-31T21:52:00+00:00", format(RFC3339_full, mtp, utc));
+  EXPECT_FALSE(parse(RFC3339_full, "1969-12-31T21:51:59+00:00", utc, &mtp));
+}
 
-  // TODO: Add tests that parsing times with fractional seconds overflow
-  // appropriately. This can't be done until cctz::parse() properly detects
-  // overflow when combining the chrono seconds and femto.
+TEST(Parse, TimePointOverflowFloor) {
+  const time_zone utc = utc_time_zone();
+
+  using D = chrono::duration<std::int64_t, std::micro>;
+  time_point<D> tp;
+
+  EXPECT_TRUE(
+      parse(RFC3339_full, "294247-01-10T04:00:54.7758079+00:00", utc, &tp));
+  EXPECT_EQ(tp, time_point<D>::max());
+  EXPECT_EQ("294247-01-10T04:00:54.775807+00:00",
+            format(RFC3339_full, tp, utc));
+#if 0
+  // TODO(#199): Will fail until cctz::parse() properly detects overflow.
+  EXPECT_FALSE(
+      parse(RFC3339_full, "294247-01-10T04:00:54.7758080+00:00", utc, &tp));
+  EXPECT_TRUE(
+      parse(RFC3339_full, "-290308-12-21T19:59:05.2241920+00:00", utc, &tp));
+  EXPECT_EQ(tp, time_point<D>::min());
+  EXPECT_EQ("-290308-12-21T19:59:05.224192+00:00",
+            format(RFC3339_full, tp, utc));
+  EXPECT_FALSE(
+      parse(RFC3339_full, "-290308-12-21T19:59:05.2241919+00:00", utc, &tp));
+#endif
 }
 
 //
diff --git a/absl/time/internal/cctz/src/time_zone_if.h b/absl/time/internal/cctz/src/time_zone_if.h
index 32c0891c..7d3e42d3 100644
--- a/absl/time/internal/cctz/src/time_zone_if.h
+++ b/absl/time/internal/cctz/src/time_zone_if.h
@@ -56,7 +56,8 @@ class TimeZoneIf {
 
 // Convert between time_point<seconds> and a count of seconds since the
 // Unix epoch.  We assume that the std::chrono::system_clock and the
-// Unix clock are second aligned, but not that they share an epoch.
+// Unix clock are second aligned, and that the results are representable.
+// (That is, that they share an epoch, which is required since C++20.)
 inline std::int_fast64_t ToUnixSeconds(const time_point<seconds>& tp) {
   return (tp - std::chrono::time_point_cast<seconds>(
                    std::chrono::system_clock::from_time_t(0)))
diff --git a/absl/time/internal/cctz/src/time_zone_info.cc b/absl/time/internal/cctz/src/time_zone_info.cc
index 8039353e..4f175d95 100644
--- a/absl/time/internal/cctz/src/time_zone_info.cc
+++ b/absl/time/internal/cctz/src/time_zone_info.cc
@@ -39,10 +39,12 @@
 #include <cstdio>
 #include <cstdlib>
 #include <cstring>
+#include <fstream>
 #include <functional>
 #include <memory>
 #include <sstream>
 #include <string>
+#include <utility>
 
 #include "absl/base/config.h"
 #include "absl/time/internal/cctz/include/cctz/civil_time.h"
@@ -576,14 +578,17 @@ bool TimeZoneInfo::Load(ZoneInfoSource* zip) {
 
 namespace {
 
+using FilePtr = std::unique_ptr<FILE, int (*)(FILE*)>;
+
 // fopen(3) adaptor.
-inline FILE* FOpen(const char* path, const char* mode) {
+inline FilePtr FOpen(const char* path, const char* mode) {
 #if defined(_MSC_VER)
   FILE* fp;
   if (fopen_s(&fp, path, mode) != 0) fp = nullptr;
-  return fp;
+  return FilePtr(fp, fclose);
 #else
-  return fopen(path, mode);  // TODO: Enable the close-on-exec flag.
+  // TODO: Enable the close-on-exec flag.
+  return FilePtr(fopen(path, mode), fclose);
 #endif
 }
 
@@ -611,11 +616,11 @@ class FileZoneInfoSource : public ZoneInfoSource {
 
  protected:
   explicit FileZoneInfoSource(
-      FILE* fp, std::size_t len = std::numeric_limits<std::size_t>::max())
-      : fp_(fp, fclose), len_(len) {}
+      FilePtr fp, std::size_t len = std::numeric_limits<std::size_t>::max())
+      : fp_(std::move(fp)), len_(len) {}
 
  private:
-  std::unique_ptr<FILE, int (*)(FILE*)> fp_;
+  FilePtr fp_;
   std::size_t len_;
 };
 
@@ -644,17 +649,9 @@ std::unique_ptr<ZoneInfoSource> FileZoneInfoSource::Open(
   path.append(name, pos, std::string::npos);
 
   // Open the zoneinfo file.
-  FILE* fp = FOpen(path.c_str(), "rb");
+  auto fp = FOpen(path.c_str(), "rb");
   if (fp == nullptr) return nullptr;
-  std::size_t length = 0;
-  if (fseek(fp, 0, SEEK_END) == 0) {
-    long offset = ftell(fp);
-    if (offset >= 0) {
-      length = static_cast<std::size_t>(offset);
-    }
-    rewind(fp);
-  }
-  return std::unique_ptr<ZoneInfoSource>(new FileZoneInfoSource(fp, length));
+  return std::unique_ptr<ZoneInfoSource>(new FileZoneInfoSource(std::move(fp)));
 }
 
 class AndroidZoneInfoSource : public FileZoneInfoSource {
@@ -663,8 +660,9 @@ class AndroidZoneInfoSource : public FileZoneInfoSource {
   std::string Version() const override { return version_; }
 
  private:
-  explicit AndroidZoneInfoSource(FILE* fp, std::size_t len, const char* vers)
-      : FileZoneInfoSource(fp, len), version_(vers) {}
+  explicit AndroidZoneInfoSource(FilePtr fp, std::size_t len,
+                                 std::string version)
+      : FileZoneInfoSource(std::move(fp), len), version_(std::move(version)) {}
   std::string version_;
 };
 
@@ -676,8 +674,8 @@ std::unique_ptr<ZoneInfoSource> AndroidZoneInfoSource::Open(
   // See Android's libc/tzcode/bionic.cpp for additional information.
   for (const char* tzdata : {"/data/misc/zoneinfo/current/tzdata",
                              "/system/usr/share/zoneinfo/tzdata"}) {
-    std::unique_ptr<FILE, int (*)(FILE*)> fp(FOpen(tzdata, "rb"), fclose);
-    if (fp.get() == nullptr) continue;
+    auto fp = FOpen(tzdata, "rb");
+    if (fp == nullptr) continue;
 
     char hbuf[24];  // covers header.zonetab_offset too
     if (fread(hbuf, 1, sizeof(hbuf), fp.get()) != sizeof(hbuf)) continue;
@@ -703,7 +701,7 @@ std::unique_ptr<ZoneInfoSource> AndroidZoneInfoSource::Open(
       if (strcmp(name.c_str() + pos, ebuf) == 0) {
         if (fseek(fp.get(), static_cast<long>(start), SEEK_SET) != 0) break;
         return std::unique_ptr<ZoneInfoSource>(new AndroidZoneInfoSource(
-            fp.release(), static_cast<std::size_t>(length), vers));
+            std::move(fp), static_cast<std::size_t>(length), vers));
       }
     }
   }
@@ -711,6 +709,69 @@ std::unique_ptr<ZoneInfoSource> AndroidZoneInfoSource::Open(
   return nullptr;
 }
 
+// A zoneinfo source for use inside Fuchsia components. This attempts to
+// read zoneinfo files from one of several known paths in a component's
+// incoming namespace. [Config data][1] is preferred, but package-specific
+// resources are also supported.
+//
+// Fuchsia's implementation supports `FileZoneInfoSource::Version()`.
+//
+// [1]:
+// https://fuchsia.dev/fuchsia-src/development/components/data#using_config_data_in_your_component
+class FuchsiaZoneInfoSource : public FileZoneInfoSource {
+ public:
+  static std::unique_ptr<ZoneInfoSource> Open(const std::string& name);
+  std::string Version() const override { return version_; }
+
+ private:
+  explicit FuchsiaZoneInfoSource(FilePtr fp, std::string version)
+      : FileZoneInfoSource(std::move(fp)), version_(std::move(version)) {}
+  std::string version_;
+};
+
+std::unique_ptr<ZoneInfoSource> FuchsiaZoneInfoSource::Open(
+    const std::string& name) {
+  // Use of the "file:" prefix is intended for testing purposes only.
+  const std::size_t pos = (name.compare(0, 5, "file:") == 0) ? 5 : 0;
+
+  // Prefixes where a Fuchsia component might find zoneinfo files,
+  // in descending order of preference.
+  const auto kTzdataPrefixes = {
+      "/config/data/tzdata/",
+      "/pkg/data/tzdata/",
+      "/data/tzdata/",
+  };
+  const auto kEmptyPrefix = {""};
+  const bool name_absolute = (pos != name.size() && name[pos] == '/');
+  const auto prefixes = name_absolute ? kEmptyPrefix : kTzdataPrefixes;
+
+  // Fuchsia builds place zoneinfo files at "<prefix><format><name>".
+  for (const std::string prefix : prefixes) {
+    std::string path = prefix;
+    if (!prefix.empty()) path += "zoneinfo/tzif2/";  // format
+    path.append(name, pos, std::string::npos);
+
+    auto fp = FOpen(path.c_str(), "rb");
+    if (fp == nullptr) continue;
+
+    std::string version;
+    if (!prefix.empty()) {
+      // Fuchsia builds place the version in "<prefix>revision.txt".
+      std::ifstream version_stream(prefix + "revision.txt");
+      if (version_stream.is_open()) {
+        // revision.txt should contain no newlines, but to be
+        // defensive we read just the first line.
+        std::getline(version_stream, version);
+      }
+    }
+
+    return std::unique_ptr<ZoneInfoSource>(
+        new FuchsiaZoneInfoSource(std::move(fp), std::move(version)));
+  }
+
+  return nullptr;
+}
+
 }  // namespace
 
 bool TimeZoneInfo::Load(const std::string& name) {
@@ -728,6 +789,7 @@ bool TimeZoneInfo::Load(const std::string& name) {
       name, [](const std::string& n) -> std::unique_ptr<ZoneInfoSource> {
         if (auto z = FileZoneInfoSource::Open(n)) return z;
         if (auto z = AndroidZoneInfoSource::Open(n)) return z;
+        if (auto z = FuchsiaZoneInfoSource::Open(n)) return z;
         return nullptr;
       });
   return zip != nullptr && Load(zip.get());
diff --git a/absl/time/internal/cctz/src/time_zone_lookup.cc b/absl/time/internal/cctz/src/time_zone_lookup.cc
index efdea64b..898d04c1 100644
--- a/absl/time/internal/cctz/src/time_zone_lookup.cc
+++ b/absl/time/internal/cctz/src/time_zone_lookup.cc
@@ -28,6 +28,13 @@
 #include <vector>
 #endif
 
+#if defined(__Fuchsia__)
+#include <fuchsia/intl/cpp/fidl.h>
+#include <lib/async-loop/cpp/loop.h>
+#include <lib/sys/cpp/component_context.h>
+#include <zircon/types.h>
+#endif
+
 #include <cstdlib>
 #include <cstring>
 #include <string>
@@ -140,6 +147,48 @@ time_zone local_time_zone() {
   }
   CFRelease(tz_default);
 #endif
+#if defined(__Fuchsia__)
+  std::string primary_tz;
+  [&]() {
+    // Note: We can't use the synchronous FIDL API here because it doesn't
+    // allow timeouts; if the FIDL call failed, local_time_zone() would never
+    // return.
+
+    const zx::duration kTimeout = zx::msec(500);
+
+    // Don't attach to the thread because otherwise the thread's dispatcher
+    // would be set to null when the loop is destroyed, causing any other FIDL
+    // code running on the same thread to crash.
+    async::Loop loop(&kAsyncLoopConfigNeverAttachToThread);
+    std::unique_ptr<sys::ComponentContext> context =
+        sys::ComponentContext::Create();
+
+    fuchsia::intl::PropertyProviderHandle handle;
+    zx_status_t status = context->svc()->Connect(handle.NewRequest());
+    if (status != ZX_OK) {
+      return;
+    }
+
+    fuchsia::intl::PropertyProviderPtr intl_provider;
+    status = intl_provider.Bind(std::move(handle), loop.dispatcher());
+    if (status != ZX_OK) {
+      return;
+    }
+
+    intl_provider->GetProfile(
+        [&loop, &primary_tz](fuchsia::intl::Profile profile) {
+          if (!profile.time_zones().empty()) {
+            primary_tz = profile.time_zones()[0].id;
+          }
+          loop.Quit();
+        });
+    loop.Run(zx::deadline_after(kTimeout));
+  }();
+
+  if (!primary_tz.empty()) {
+    zone = primary_tz.c_str();
+  }
+#endif
 
   // Allow ${TZ} to override to default zone.
   char* tz_env = nullptr;
diff --git a/absl/time/internal/cctz/src/time_zone_lookup_test.cc b/absl/time/internal/cctz/src/time_zone_lookup_test.cc
index 9a1a8d6e..27a53c5c 100644
--- a/absl/time/internal/cctz/src/time_zone_lookup_test.cc
+++ b/absl/time/internal/cctz/src/time_zone_lookup_test.cc
@@ -21,10 +21,14 @@
 #include <thread>
 #include <vector>
 
-#include "gtest/gtest.h"
 #include "absl/base/config.h"
-#include "absl/time/internal/cctz/include/cctz/civil_time.h"
 #include "absl/time/internal/cctz/include/cctz/time_zone.h"
+#if defined(__linux__)
+#include <features.h>
+#endif
+
+#include "gtest/gtest.h"
+#include "absl/time/internal/cctz/include/cctz/civil_time.h"
 
 namespace chrono = std::chrono;
 
@@ -579,6 +583,7 @@ const char* const kTimeZoneNames[] = {"Africa/Abidjan",
                                       "Pacific/Guam",
                                       "Pacific/Honolulu",
                                       "Pacific/Johnston",
+                                      "Pacific/Kanton",
                                       "Pacific/Kiritimati",
                                       "Pacific/Kosrae",
                                       "Pacific/Kwajalein",
@@ -717,6 +722,18 @@ TEST(TimeZones, LoadZonesConcurrently) {
 }
 #endif
 
+TEST(TimeZone, UTC) {
+  const time_zone utc = utc_time_zone();
+
+  time_zone loaded_utc;
+  EXPECT_TRUE(load_time_zone("UTC", &loaded_utc));
+  EXPECT_EQ(loaded_utc, utc);
+
+  time_zone loaded_utc0;
+  EXPECT_TRUE(load_time_zone("UTC0", &loaded_utc0));
+  EXPECT_EQ(loaded_utc0, utc);
+}
+
 TEST(TimeZone, NamedTimeZones) {
   const time_zone utc = utc_time_zone();
   EXPECT_EQ("UTC", utc.name());
@@ -1014,8 +1031,12 @@ TEST(MakeTime, SysSecondsLimits) {
 #endif
     const year_t min_tm_year = year_t{std::numeric_limits<int>::min()} + 1900;
     tp = convert(civil_second(min_tm_year, 1, 1, 0, 0, 0), cut);
+#if defined(__Fuchsia__)
+    // Fuchsia's gmtime_r() fails on extreme negative values (fxbug.dev/78527).
+#else
     EXPECT_EQ("-2147481748-01-01T00:00:00+00:00", format(RFC3339, tp, cut));
 #endif
+#endif
   }
 }
 
@@ -1026,7 +1047,7 @@ TEST(MakeTime, LocalTimeLibC) {
   //  1) we know how to change the time zone used by localtime()/mktime(),
   //  2) cctz and localtime()/mktime() will use similar-enough tzdata, and
   //  3) we have some idea about how mktime() behaves during transitions.
-#if defined(__linux__) && !defined(__ANDROID__)
+#if defined(__linux__) && defined(__GLIBC__) && !defined(__ANDROID__)
   const char* const ep = getenv("TZ");
   std::string tz_name = (ep != nullptr) ? ep : "";
   for (const char* const* np = kTimeZoneNames; *np != nullptr; ++np) {
@@ -1165,6 +1186,44 @@ TEST(PrevTransition, AmericaNewYork) {
   // We have a transition but we don't know which one.
 }
 
+TEST(NextTransition, Scan) {
+  for (const char* const* np = kTimeZoneNames; *np != nullptr; ++np) {
+    time_zone tz;
+    if (!load_time_zone(*np, &tz)) {
+      continue;  // tolerate kTimeZoneNames/zoneinfo skew
+    }
+    SCOPED_TRACE(testing::Message() << "In " << *np);
+
+    auto tp = time_point<absl::time_internal::cctz::seconds>::min();
+    time_zone::civil_transition trans;
+    while (tz.next_transition(tp, &trans)) {
+      time_zone::civil_lookup from_cl = tz.lookup(trans.from);
+      EXPECT_NE(from_cl.kind, time_zone::civil_lookup::REPEATED);
+      time_zone::civil_lookup to_cl = tz.lookup(trans.to);
+      EXPECT_NE(to_cl.kind, time_zone::civil_lookup::SKIPPED);
+
+      auto trans_tp = to_cl.trans;
+      time_zone::absolute_lookup trans_al = tz.lookup(trans_tp);
+      EXPECT_EQ(trans_al.cs, trans.to);
+      auto pre_trans_tp = trans_tp - absl::time_internal::cctz::seconds(1);
+      time_zone::absolute_lookup pre_trans_al = tz.lookup(pre_trans_tp);
+      EXPECT_EQ(pre_trans_al.cs + 1, trans.from);
+
+      auto offset_delta = trans_al.offset - pre_trans_al.offset;
+      EXPECT_EQ(offset_delta, trans.to - trans.from);
+      if (offset_delta == 0) {
+        // This "transition" is only an is_dst or abbr change.
+        EXPECT_EQ(to_cl.kind, time_zone::civil_lookup::UNIQUE);
+        if (trans_al.is_dst == pre_trans_al.is_dst) {
+          EXPECT_STRNE(trans_al.abbr, pre_trans_al.abbr);
+        }
+      }
+
+      tp = trans_tp;  // continue scan from transition
+    }
+  }
+}
+
 TEST(TimeZoneEdgeCase, AmericaNewYork) {
   const time_zone tz = LoadZone("America/New_York");
 
diff --git a/absl/time/internal/cctz/src/tzfile.h b/absl/time/internal/cctz/src/tzfile.h
index 269fa36c..31e85982 100644
--- a/absl/time/internal/cctz/src/tzfile.h
+++ b/absl/time/internal/cctz/src/tzfile.h
@@ -43,7 +43,7 @@
 
 struct tzhead {
   char tzh_magic[4];      /* TZ_MAGIC */
-  char tzh_version[1];    /* '\0' or '2' or '3' as of 2013 */
+  char tzh_version[1];    /* '\0' or '2'-'4' as of 2021 */
   char tzh_reserved[15];  /* reserved; must be zero */
   char tzh_ttisutcnt[4];  /* coded number of trans. time flags */
   char tzh_ttisstdcnt[4]; /* coded number of trans. time flags */
diff --git a/absl/time/internal/cctz/src/zone_info_source.cc b/absl/time/internal/cctz/src/zone_info_source.cc
index 72095339..5ab5a59e 100644
--- a/absl/time/internal/cctz/src/zone_info_source.cc
+++ b/absl/time/internal/cctz/src/zone_info_source.cc
@@ -65,7 +65,7 @@ ZoneInfoSourceFactory zone_info_source_factory __attribute__((weak)) =
 extern ZoneInfoSourceFactory zone_info_source_factory;
 extern ZoneInfoSourceFactory default_factory;
 ZoneInfoSourceFactory default_factory = DefaultFactory;
-#if defined(_M_IX86)
+#if defined(_M_IX86) || defined(_M_ARM)
 #pragma comment(                                                                                                         \
     linker,                                                                                                              \
     "/alternatename:?zone_info_source_factory@cctz_extension@time_internal@" ABSL_INTERNAL_MANGLED_NS                    \
@@ -83,8 +83,7 @@ ZoneInfoSourceFactory default_factory = DefaultFactory;
     "@@U?$default_delete@VZoneInfoSource@cctz@time_internal@" ABSL_INTERNAL_MANGLED_NS                                   \
     "@@@std@@@std@@ABV?$basic_string@DU?$char_traits@D@std@@V?$allocator@D@2@@2@@Z@" ABSL_INTERNAL_MANGLED_BACKREFERENCE \
     "@@ZA")
-#elif defined(_M_IA_64) || defined(_M_AMD64) || defined(_M_ARM) || \
-    defined(_M_ARM64)
+#elif defined(_M_IA_64) || defined(_M_AMD64) || defined(_M_ARM64)
 #pragma comment(                                                                                                          \
     linker,                                                                                                               \
     "/alternatename:?zone_info_source_factory@cctz_extension@time_internal@" ABSL_INTERNAL_MANGLED_NS                     \
diff --git a/absl/time/internal/cctz/testdata/README.zoneinfo b/absl/time/internal/cctz/testdata/README.zoneinfo
index 95fb4a91..a41c7b88 100644
--- a/absl/time/internal/cctz/testdata/README.zoneinfo
+++ b/absl/time/internal/cctz/testdata/README.zoneinfo
@@ -13,7 +13,12 @@ New versions can be generated using the following shell script.
   trap "rm -fr ${DESTDIR}" 0 2 15
   (
     cd ${DESTDIR}
-    git clone https://github.com/eggert/tz.git
+    if [ -n "${USE_GLOBAL_TZ}" ]
+    then
+      git clone -b global-tz https://github.com/JodaOrg/global-tz.git tz
+    else
+      git clone https://github.com/eggert/tz.git
+    fi
     make --directory=tz \
         install DESTDIR=${DESTDIR} \
                 DATAFORM=vanguard \
diff --git a/absl/time/internal/cctz/testdata/version b/absl/time/internal/cctz/testdata/version
index 1d590958..ca002de2 100644
--- a/absl/time/internal/cctz/testdata/version
+++ b/absl/time/internal/cctz/testdata/version
@@ -1 +1 @@
-2021a
+2022a
diff --git a/absl/time/internal/cctz/testdata/zoneinfo/Africa/Accra b/absl/time/internal/cctz/testdata/zoneinfo/Africa/Accra
index c39ae382..8906e88c 100644
--- a/absl/time/internal/cctz/testdata/zoneinfo/Africa/Accra
+++ b/absl/time/internal/cctz/testdata/zoneinfo/Africa/Accra
diff --git a/absl/time/internal/cctz/testdata/zoneinfo/America/Anguilla b/absl/time/internal/cctz/testdata/zoneinfo/America/Anguilla
index f4fe5903..47b4dc34 100644
--- a/absl/time/internal/cctz/testdata/zoneinfo/America/Anguilla
+++ b/absl/time/internal/cctz/testdata/zoneinfo/America/Anguilla
diff --git a/absl/time/internal/cctz/testdata/zoneinfo/America/Antigua b/absl/time/internal/cctz/testdata/zoneinfo/America/Antigua
index f4fe5903..47b4dc34 100644
--- a/absl/time/internal/cctz/testdata/zoneinfo/America/Antigua
+++ b/absl/time/internal/cctz/testdata/zoneinfo/America/Antigua
diff --git a/absl/time/internal/cctz/testdata/zoneinfo/America/Aruba b/absl/time/internal/cctz/testdata/zoneinfo/America/Aruba
index d6ddf7d8..47b4dc34 100644
--- a/absl/time/internal/cctz/testdata/zoneinfo/America/Aruba
+++ b/absl/time/internal/cctz/testdata/zoneinfo/America/Aruba
diff --git a/absl/time/internal/cctz/testdata/zoneinfo/America/Atikokan b/absl/time/internal/cctz/testdata/zoneinfo/America/Atikokan
index c8287152..9154643f 100644
--- a/absl/time/internal/cctz/testdata/zoneinfo/America/Atikokan
+++ b/absl/time/internal/cctz/testdata/zoneinfo/America/Atikokan
diff --git a/absl/time/internal/cctz/testdata/zoneinfo/America/Barbados b/absl/time/internal/cctz/testdata/zoneinfo/America/Barbados
index 9d3afa6a..720c9863 100644
--- a/absl/time/internal/cctz/testdata/zoneinfo/America/Barbados
+++ b/absl/time/internal/cctz/testdata/zoneinfo/America/Barbados
diff --git a/absl/time/internal/cctz/testdata/zoneinfo/America/Blanc-Sablon b/absl/time/internal/cctz/testdata/zoneinfo/America/Blanc-Sablon
index 7096b69a..47b4dc34 100644
--- a/absl/time/internal/cctz/testdata/zoneinfo/America/Blanc-Sablon
+++ b/absl/time/internal/cctz/testdata/zoneinfo/America/Blanc-Sablon
diff --git a/absl/time/internal/cctz/testdata/zoneinfo/America/Coral_Harbour b/absl/time/internal/cctz/testdata/zoneinfo/America/Coral_Harbour
index c8287152..9154643f 100644
--- a/absl/time/internal/cctz/testdata/zoneinfo/America/Coral_Harbour
+++ b/absl/time/internal/cctz/testdata/zoneinfo/America/Coral_Harbour
diff --git a/absl/time/internal/cctz/testdata/zoneinfo/America/Creston b/absl/time/internal/cctz/testdata/zoneinfo/America/Creston
index 9d69a0ab..c2bd2f94 100644
--- a/absl/time/internal/cctz/testdata/zoneinfo/America/Creston
+++ b/absl/time/internal/cctz/testdata/zoneinfo/America/Creston
diff --git a/absl/time/internal/cctz/testdata/zoneinfo/America/Curacao b/absl/time/internal/cctz/testdata/zoneinfo/America/Curacao
index d6ddf7d8..47b4dc34 100644
--- a/absl/time/internal/cctz/testdata/zoneinfo/America/Curacao
+++ b/absl/time/internal/cctz/testdata/zoneinfo/America/Curacao
diff --git a/absl/time/internal/cctz/testdata/zoneinfo/America/Dominica b/absl/time/internal/cctz/testdata/zoneinfo/America/Dominica
index f4fe5903..47b4dc34 100644
--- a/absl/time/internal/cctz/testdata/zoneinfo/America/Dominica
+++ b/absl/time/internal/cctz/testdata/zoneinfo/America/Dominica
diff --git a/absl/time/internal/cctz/testdata/zoneinfo/America/Grenada b/absl/time/internal/cctz/testdata/zoneinfo/America/Grenada
index f4fe5903..47b4dc34 100644
--- a/absl/time/internal/cctz/testdata/zoneinfo/America/Grenada
+++ b/absl/time/internal/cctz/testdata/zoneinfo/America/Grenada
diff --git a/absl/time/internal/cctz/testdata/zoneinfo/America/Guadeloupe b/absl/time/internal/cctz/testdata/zoneinfo/America/Guadeloupe
index f4fe5903..47b4dc34 100644
--- a/absl/time/internal/cctz/testdata/zoneinfo/America/Guadeloupe
+++ b/absl/time/internal/cctz/testdata/zoneinfo/America/Guadeloupe
diff --git a/absl/time/internal/cctz/testdata/zoneinfo/America/Guyana b/absl/time/internal/cctz/testdata/zoneinfo/America/Guyana
index ebd85d0f..bcc66881 100644
--- a/absl/time/internal/cctz/testdata/zoneinfo/America/Guyana
+++ b/absl/time/internal/cctz/testdata/zoneinfo/America/Guyana
diff --git a/absl/time/internal/cctz/testdata/zoneinfo/America/Kralendijk b/absl/time/internal/cctz/testdata/zoneinfo/America/Kralendijk
index d6ddf7d8..47b4dc34 100644
--- a/absl/time/internal/cctz/testdata/zoneinfo/America/Kralendijk
+++ b/absl/time/internal/cctz/testdata/zoneinfo/America/Kralendijk
diff --git a/absl/time/internal/cctz/testdata/zoneinfo/America/Lower_Princes b/absl/time/internal/cctz/testdata/zoneinfo/America/Lower_Princes
index d6ddf7d8..47b4dc34 100644
--- a/absl/time/internal/cctz/testdata/zoneinfo/America/Lower_Princes
+++ b/absl/time/internal/cctz/testdata/zoneinfo/America/Lower_Princes
diff --git a/absl/time/internal/cctz/testdata/zoneinfo/America/Marigot b/absl/time/internal/cctz/testdata/zoneinfo/America/Marigot
index f4fe5903..47b4dc34 100644
--- a/absl/time/internal/cctz/testdata/zoneinfo/America/Marigot
+++ b/absl/time/internal/cctz/testdata/zoneinfo/America/Marigot
diff --git a/absl/time/internal/cctz/testdata/zoneinfo/America/Montserrat b/absl/time/internal/cctz/testdata/zoneinfo/America/Montserrat
index f4fe5903..47b4dc34 100644
--- a/absl/time/internal/cctz/testdata/zoneinfo/America/Montserrat
+++ b/absl/time/internal/cctz/testdata/zoneinfo/America/Montserrat
diff --git a/absl/time/internal/cctz/testdata/zoneinfo/America/Nassau b/absl/time/internal/cctz/testdata/zoneinfo/America/Nassau
index 2ef2aa89..fe6be8ea 100644
--- a/absl/time/internal/cctz/testdata/zoneinfo/America/Nassau
+++ b/absl/time/internal/cctz/testdata/zoneinfo/America/Nassau
diff --git a/absl/time/internal/cctz/testdata/zoneinfo/America/Port_of_Spain b/absl/time/internal/cctz/testdata/zoneinfo/America/Port_of_Spain
index f4fe5903..47b4dc34 100644
--- a/absl/time/internal/cctz/testdata/zoneinfo/America/Port_of_Spain
+++ b/absl/time/internal/cctz/testdata/zoneinfo/America/Port_of_Spain
diff --git a/absl/time/internal/cctz/testdata/zoneinfo/America/Punta_Arenas b/absl/time/internal/cctz/testdata/zoneinfo/America/Punta_Arenas
index 5c9a20b9..c0421040 100644
--- a/absl/time/internal/cctz/testdata/zoneinfo/America/Punta_Arenas
+++ b/absl/time/internal/cctz/testdata/zoneinfo/America/Punta_Arenas
diff --git a/absl/time/internal/cctz/testdata/zoneinfo/America/Santiago b/absl/time/internal/cctz/testdata/zoneinfo/America/Santiago
index 8d603226..cde8dbbf 100644
--- a/absl/time/internal/cctz/testdata/zoneinfo/America/Santiago
+++ b/absl/time/internal/cctz/testdata/zoneinfo/America/Santiago
diff --git a/absl/time/internal/cctz/testdata/zoneinfo/America/St_Barthelemy b/absl/time/internal/cctz/testdata/zoneinfo/America/St_Barthelemy
index f4fe5903..47b4dc34 100644
--- a/absl/time/internal/cctz/testdata/zoneinfo/America/St_Barthelemy
+++ b/absl/time/internal/cctz/testdata/zoneinfo/America/St_Barthelemy
diff --git a/absl/time/internal/cctz/testdata/zoneinfo/America/St_Kitts b/absl/time/internal/cctz/testdata/zoneinfo/America/St_Kitts
index f4fe5903..47b4dc34 100644
--- a/absl/time/internal/cctz/testdata/zoneinfo/America/St_Kitts
+++ b/absl/time/internal/cctz/testdata/zoneinfo/America/St_Kitts
diff --git a/absl/time/internal/cctz/testdata/zoneinfo/America/St_Lucia b/absl/time/internal/cctz/testdata/zoneinfo/America/St_Lucia
index f4fe5903..47b4dc34 100644
--- a/absl/time/internal/cctz/testdata/zoneinfo/America/St_Lucia
+++ b/absl/time/internal/cctz/testdata/zoneinfo/America/St_Lucia
diff --git a/absl/time/internal/cctz/testdata/zoneinfo/America/St_Thomas b/absl/time/internal/cctz/testdata/zoneinfo/America/St_Thomas
index f4fe5903..47b4dc34 100644
--- a/absl/time/internal/cctz/testdata/zoneinfo/America/St_Thomas
+++ b/absl/time/internal/cctz/testdata/zoneinfo/America/St_Thomas
diff --git a/absl/time/internal/cctz/testdata/zoneinfo/America/St_Vincent b/absl/time/internal/cctz/testdata/zoneinfo/America/St_Vincent
index f4fe5903..47b4dc34 100644
--- a/absl/time/internal/cctz/testdata/zoneinfo/America/St_Vincent
+++ b/absl/time/internal/cctz/testdata/zoneinfo/America/St_Vincent
diff --git a/absl/time/internal/cctz/testdata/zoneinfo/America/Tortola b/absl/time/internal/cctz/testdata/zoneinfo/America/Tortola
index f4fe5903..47b4dc34 100644
--- a/absl/time/internal/cctz/testdata/zoneinfo/America/Tortola
+++ b/absl/time/internal/cctz/testdata/zoneinfo/America/Tortola
diff --git a/absl/time/internal/cctz/testdata/zoneinfo/America/Virgin b/absl/time/internal/cctz/testdata/zoneinfo/America/Virgin
index f4fe5903..47b4dc34 100644
--- a/absl/time/internal/cctz/testdata/zoneinfo/America/Virgin
+++ b/absl/time/internal/cctz/testdata/zoneinfo/America/Virgin
diff --git a/absl/time/internal/cctz/testdata/zoneinfo/Antarctica/DumontDUrville b/absl/time/internal/cctz/testdata/zoneinfo/Antarctica/DumontDUrville
index c0cfc85a..5d8fc3a1 100644
--- a/absl/time/internal/cctz/testdata/zoneinfo/Antarctica/DumontDUrville
+++ b/absl/time/internal/cctz/testdata/zoneinfo/Antarctica/DumontDUrville
diff --git a/absl/time/internal/cctz/testdata/zoneinfo/Antarctica/Syowa b/absl/time/internal/cctz/testdata/zoneinfo/Antarctica/Syowa
index 97d80d75..01c47ccb 100644
--- a/absl/time/internal/cctz/testdata/zoneinfo/Antarctica/Syowa
+++ b/absl/time/internal/cctz/testdata/zoneinfo/Antarctica/Syowa
diff --git a/absl/time/internal/cctz/testdata/zoneinfo/Asia/Amman b/absl/time/internal/cctz/testdata/zoneinfo/Asia/Amman
index 1bd09fef..d97d308d 100644
--- a/absl/time/internal/cctz/testdata/zoneinfo/Asia/Amman
+++ b/absl/time/internal/cctz/testdata/zoneinfo/Asia/Amman
diff --git a/absl/time/internal/cctz/testdata/zoneinfo/Asia/Gaza b/absl/time/internal/cctz/testdata/zoneinfo/Asia/Gaza
index 58e9fdf4..effc4df5 100644
--- a/absl/time/internal/cctz/testdata/zoneinfo/Asia/Gaza
+++ b/absl/time/internal/cctz/testdata/zoneinfo/Asia/Gaza
diff --git a/absl/time/internal/cctz/testdata/zoneinfo/Asia/Hebron b/absl/time/internal/cctz/testdata/zoneinfo/Asia/Hebron
index aeda06b5..aa52bd26 100644
--- a/absl/time/internal/cctz/testdata/zoneinfo/Asia/Hebron
+++ b/absl/time/internal/cctz/testdata/zoneinfo/Asia/Hebron
diff --git a/absl/time/internal/cctz/testdata/zoneinfo/Atlantic/Azores b/absl/time/internal/cctz/testdata/zoneinfo/Atlantic/Azores
index b7f75a9c..e6e2616e 100644
--- a/absl/time/internal/cctz/testdata/zoneinfo/Atlantic/Azores
+++ b/absl/time/internal/cctz/testdata/zoneinfo/Atlantic/Azores
diff --git a/absl/time/internal/cctz/testdata/zoneinfo/Atlantic/Madeira b/absl/time/internal/cctz/testdata/zoneinfo/Atlantic/Madeira
index 7c3a49c0..cf965c3f 100644
--- a/absl/time/internal/cctz/testdata/zoneinfo/Atlantic/Madeira
+++ b/absl/time/internal/cctz/testdata/zoneinfo/Atlantic/Madeira
diff --git a/absl/time/internal/cctz/testdata/zoneinfo/Chile/Continental b/absl/time/internal/cctz/testdata/zoneinfo/Chile/Continental
index 8d603226..cde8dbbf 100644
--- a/absl/time/internal/cctz/testdata/zoneinfo/Chile/Continental
+++ b/absl/time/internal/cctz/testdata/zoneinfo/Chile/Continental
diff --git a/absl/time/internal/cctz/testdata/zoneinfo/Europe/Kiev b/absl/time/internal/cctz/testdata/zoneinfo/Europe/Kiev
index 8f83cefb..4e026859 100644
--- a/absl/time/internal/cctz/testdata/zoneinfo/Europe/Kiev
+++ b/absl/time/internal/cctz/testdata/zoneinfo/Europe/Kiev
diff --git a/absl/time/internal/cctz/testdata/zoneinfo/Europe/Lisbon b/absl/time/internal/cctz/testdata/zoneinfo/Europe/Lisbon
index 64841661..f0c70b69 100644
--- a/absl/time/internal/cctz/testdata/zoneinfo/Europe/Lisbon
+++ b/absl/time/internal/cctz/testdata/zoneinfo/Europe/Lisbon
diff --git a/absl/time/internal/cctz/testdata/zoneinfo/Europe/Simferopol b/absl/time/internal/cctz/testdata/zoneinfo/Europe/Simferopol
index 88a6f3bd..40d23c02 100644
--- a/absl/time/internal/cctz/testdata/zoneinfo/Europe/Simferopol
+++ b/absl/time/internal/cctz/testdata/zoneinfo/Europe/Simferopol
diff --git a/absl/time/internal/cctz/testdata/zoneinfo/Europe/Uzhgorod b/absl/time/internal/cctz/testdata/zoneinfo/Europe/Uzhgorod
index a5755685..d4c35914 100644
--- a/absl/time/internal/cctz/testdata/zoneinfo/Europe/Uzhgorod
+++ b/absl/time/internal/cctz/testdata/zoneinfo/Europe/Uzhgorod
diff --git a/absl/time/internal/cctz/testdata/zoneinfo/Europe/Zaporozhye b/absl/time/internal/cctz/testdata/zoneinfo/Europe/Zaporozhye
index 4ea8dae4..71819a5a 100644
--- a/absl/time/internal/cctz/testdata/zoneinfo/Europe/Zaporozhye
+++ b/absl/time/internal/cctz/testdata/zoneinfo/Europe/Zaporozhye
diff --git a/absl/time/internal/cctz/testdata/zoneinfo/Pacific/Apia b/absl/time/internal/cctz/testdata/zoneinfo/Pacific/Apia
index 244af26f..a6b835aa 100644
--- a/absl/time/internal/cctz/testdata/zoneinfo/Pacific/Apia
+++ b/absl/time/internal/cctz/testdata/zoneinfo/Pacific/Apia
diff --git a/absl/time/internal/cctz/testdata/zoneinfo/Pacific/Enderbury b/absl/time/internal/cctz/testdata/zoneinfo/Pacific/Enderbury
index b22ab147..2b6a0608 100644
--- a/absl/time/internal/cctz/testdata/zoneinfo/Pacific/Enderbury
+++ b/absl/time/internal/cctz/testdata/zoneinfo/Pacific/Enderbury
diff --git a/absl/time/internal/cctz/testdata/zoneinfo/Pacific/Fiji b/absl/time/internal/cctz/testdata/zoneinfo/Pacific/Fiji
index e3934e42..8b2dd52b 100644
--- a/absl/time/internal/cctz/testdata/zoneinfo/Pacific/Fiji
+++ b/absl/time/internal/cctz/testdata/zoneinfo/Pacific/Fiji
diff --git a/absl/time/internal/cctz/testdata/zoneinfo/Pacific/Kanton b/absl/time/internal/cctz/testdata/zoneinfo/Pacific/Kanton
new file mode 100644
index 00000000..2b6a0608
--- /dev/null
+++ b/absl/time/internal/cctz/testdata/zoneinfo/Pacific/Kanton
diff --git a/absl/time/internal/cctz/testdata/zoneinfo/Pacific/Niue b/absl/time/internal/cctz/testdata/zoneinfo/Pacific/Niue
index 7b357935..be874e24 100644
--- a/absl/time/internal/cctz/testdata/zoneinfo/Pacific/Niue
+++ b/absl/time/internal/cctz/testdata/zoneinfo/Pacific/Niue
diff --git a/absl/time/internal/cctz/testdata/zoneinfo/Pacific/Rarotonga b/absl/time/internal/cctz/testdata/zoneinfo/Pacific/Rarotonga
index 143a1883..7220bda0 100644
--- a/absl/time/internal/cctz/testdata/zoneinfo/Pacific/Rarotonga
+++ b/absl/time/internal/cctz/testdata/zoneinfo/Pacific/Rarotonga
diff --git a/absl/time/internal/cctz/testdata/zoneinfo/Pacific/Tongatapu b/absl/time/internal/cctz/testdata/zoneinfo/Pacific/Tongatapu
index 54aeb0ff..f28c8401 100644
--- a/absl/time/internal/cctz/testdata/zoneinfo/Pacific/Tongatapu
+++ b/absl/time/internal/cctz/testdata/zoneinfo/Pacific/Tongatapu
diff --git a/absl/time/internal/cctz/testdata/zoneinfo/Portugal b/absl/time/internal/cctz/testdata/zoneinfo/Portugal
index 64841661..f0c70b69 100644
--- a/absl/time/internal/cctz/testdata/zoneinfo/Portugal
+++ b/absl/time/internal/cctz/testdata/zoneinfo/Portugal
diff --git a/absl/time/internal/cctz/testdata/zoneinfo/zone1970.tab b/absl/time/internal/cctz/testdata/zoneinfo/zone1970.tab
index 396e4d38..c614be81 100644
--- a/absl/time/internal/cctz/testdata/zoneinfo/zone1970.tab
+++ b/absl/time/internal/cctz/testdata/zoneinfo/zone1970.tab
@@ -40,11 +40,9 @@ AL	+4120+01950	Europe/Tirane
 AM	+4011+04430	Asia/Yerevan
 AQ	-6617+11031	Antarctica/Casey	Casey
 AQ	-6835+07758	Antarctica/Davis	Davis
-AQ	-6640+14001	Antarctica/DumontDUrville	Dumont-d'Urville
 AQ	-6736+06253	Antarctica/Mawson	Mawson
 AQ	-6448-06406	Antarctica/Palmer	Palmer
 AQ	-6734-06808	Antarctica/Rothera	Rothera
-AQ	-690022+0393524	Antarctica/Syowa	Syowa
 AQ	-720041+0023206	Antarctica/Troll	Troll
 AQ	-7824+10654	Antarctica/Vostok	Vostok
 AR	-3436-05827	America/Argentina/Buenos_Aires	Buenos Aires (BA, CF)
@@ -97,7 +95,6 @@ BR	+0249-06040	America/Boa_Vista	Roraima
 BR	-0308-06001	America/Manaus	Amazonas (east)
 BR	-0640-06952	America/Eirunepe	Amazonas (west)
 BR	-0958-06748	America/Rio_Branco	Acre
-BS	+2505-07721	America/Nassau
 BT	+2728+08939	Asia/Thimphu
 BY	+5354+02734	Europe/Minsk
 BZ	+1730-08812	America/Belize
@@ -106,13 +103,11 @@ CA	+4439-06336	America/Halifax	Atlantic - NS (most areas); PE
 CA	+4612-05957	America/Glace_Bay	Atlantic - NS (Cape Breton)
 CA	+4606-06447	America/Moncton	Atlantic - New Brunswick
 CA	+5320-06025	America/Goose_Bay	Atlantic - Labrador (most areas)
-CA	+5125-05707	America/Blanc-Sablon	AST - QC (Lower North Shore)
-CA	+4339-07923	America/Toronto	Eastern - ON, QC (most areas)
+CA,BS	+4339-07923	America/Toronto	Eastern - ON, QC (most areas), Bahamas
 CA	+4901-08816	America/Nipigon	Eastern - ON, QC (no DST 1967-73)
 CA	+4823-08915	America/Thunder_Bay	Eastern - ON (Thunder Bay)
 CA	+6344-06828	America/Iqaluit	Eastern - NU (most east areas)
 CA	+6608-06544	America/Pangnirtung	Eastern - NU (Pangnirtung)
-CA	+484531-0913718	America/Atikokan	EST - ON (Atikokan); NU (Coral H)
 CA	+4953-09709	America/Winnipeg	Central - ON (west); Manitoba
 CA	+4843-09434	America/Rainy_River	Central - ON (Rainy R, Ft Frances)
 CA	+744144-0944945	America/Resolute	Central - NU (Resolute)
@@ -123,7 +118,6 @@ CA	+5333-11328	America/Edmonton	Mountain - AB; BC (E); SK (W)
 CA	+690650-1050310	America/Cambridge_Bay	Mountain - NU (west)
 CA	+6227-11421	America/Yellowknife	Mountain - NT (central)
 CA	+682059-1334300	America/Inuvik	Mountain - NT (west)
-CA	+4906-11631	America/Creston	MST - BC (Creston)
 CA	+5946-12014	America/Dawson_Creek	MST - BC (Dawson Cr, Ft St John)
 CA	+5848-12242	America/Fort_Nelson	MST - BC (Ft Nelson)
 CA	+6043-13503	America/Whitehorse	MST - Yukon (east)
@@ -131,7 +125,7 @@ CA	+6404-13925	America/Dawson	MST - Yukon (west)
 CA	+4916-12307	America/Vancouver	Pacific - BC (most areas)
 CC	-1210+09655	Indian/Cocos
 CH,DE,LI	+4723+00832	Europe/Zurich	Swiss time
-CI,BF,GM,GN,ML,MR,SH,SL,SN,TG	+0519-00402	Africa/Abidjan
+CI,BF,GH,GM,GN,ML,MR,SH,SL,SN,TG	+0519-00402	Africa/Abidjan
 CK	-2114-15946	Pacific/Rarotonga
 CL	-3327-07040	America/Santiago	Chile (most areas)
 CL	-5309-07055	America/Punta_Arenas	Region of Magallanes
@@ -142,7 +136,6 @@ CO	+0436-07405	America/Bogota
 CR	+0956-08405	America/Costa_Rica
 CU	+2308-08222	America/Havana
 CV	+1455-02331	Atlantic/Cape_Verde
-CW,AW,BQ,SX	+1211-06900	America/Curacao
 CX	-1025+10543	Indian/Christmas
 CY	+3510+03322	Asia/Nicosia	Cyprus (most areas)
 CY	+3507+03357	Asia/Famagusta	Northern Cyprus
@@ -170,7 +163,6 @@ FR	+4852+00220	Europe/Paris
 GB,GG,IM,JE	+513030-0000731	Europe/London
 GE	+4143+04449	Asia/Tbilisi
 GF	+0456-05220	America/Cayenne
-GH	+0533-00013	Africa/Accra
 GI	+3608-00521	Europe/Gibraltar
 GL	+6411-05144	America/Nuuk	Greenland (most areas)
 GL	+7646-01840	America/Danmarkshavn	National Park (east coast)
@@ -204,7 +196,7 @@ JP	+353916+1394441	Asia/Tokyo
 KE,DJ,ER,ET,KM,MG,SO,TZ,UG,YT	-0117+03649	Africa/Nairobi
 KG	+4254+07436	Asia/Bishkek
 KI	+0125+17300	Pacific/Tarawa	Gilbert Islands
-KI	-0308-17105	Pacific/Enderbury	Phoenix Islands
+KI	-0247-17143	Pacific/Kanton	Phoenix Islands
 KI	+0152-15720	Pacific/Kiritimati	Line Islands
 KP	+3901+12545	Asia/Pyongyang
 KR	+3733+12658	Asia/Seoul
@@ -262,19 +254,19 @@ NR	-0031+16655	Pacific/Nauru
 NU	-1901-16955	Pacific/Niue
 NZ,AQ	-3652+17446	Pacific/Auckland	New Zealand time
 NZ	-4357-17633	Pacific/Chatham	Chatham Islands
-PA,KY	+0858-07932	America/Panama
+PA,CA,KY	+0858-07932	America/Panama	EST - Panama, Cayman, ON (Atikokan), NU (Coral H)
 PE	-1203-07703	America/Lima
 PF	-1732-14934	Pacific/Tahiti	Society Islands
 PF	-0900-13930	Pacific/Marquesas	Marquesas Islands
 PF	-2308-13457	Pacific/Gambier	Gambier Islands
-PG	-0930+14710	Pacific/Port_Moresby	Papua New Guinea (most areas)
+PG,AQ	-0930+14710	Pacific/Port_Moresby	Papua New Guinea (most areas), Dumont d'Urville
 PG	-0613+15534	Pacific/Bougainville	Bougainville
 PH	+1435+12100	Asia/Manila
 PK	+2452+06703	Asia/Karachi
 PL	+5215+02100	Europe/Warsaw
 PM	+4703-05620	America/Miquelon
 PN	-2504-13005	Pacific/Pitcairn
-PR	+182806-0660622	America/Puerto_Rico
+PR,AG,CA,AI,AW,BL,BQ,CW,DM,GD,GP,KN,LC,MF,MS,SX,TT,VC,VG,VI	+182806-0660622	America/Puerto_Rico	AST
 PS	+3130+03428	Asia/Gaza	Gaza Strip
 PS	+313200+0350542	Asia/Hebron	West Bank
 PT	+3843-00908	Europe/Lisbon	Portugal (mainland)
@@ -314,12 +306,12 @@ RU	+4658+14242	Asia/Sakhalin	MSK+08 - Sakhalin Island
 RU	+6728+15343	Asia/Srednekolymsk	MSK+08 - Sakha (E); North Kuril Is
 RU	+5301+15839	Asia/Kamchatka	MSK+09 - Kamchatka
 RU	+6445+17729	Asia/Anadyr	MSK+09 - Bering Sea
-SA,KW,YE	+2438+04643	Asia/Riyadh
+SA,AQ,KW,YE	+2438+04643	Asia/Riyadh	Arabia, Syowa
 SB	-0932+16012	Pacific/Guadalcanal
 SC	-0440+05528	Indian/Mahe
 SD	+1536+03232	Africa/Khartoum
 SE	+5920+01803	Europe/Stockholm
-SG	+0117+10351	Asia/Singapore
+SG,MY	+0117+10351	Asia/Singapore	Singapore, peninsular Malaysia
 SR	+0550-05510	America/Paramaribo
 SS	+0451+03137	Africa/Juba
 ST	+0020+00644	Africa/Sao_Tome
@@ -334,9 +326,8 @@ TK	-0922-17114	Pacific/Fakaofo
 TL	-0833+12535	Asia/Dili
 TM	+3757+05823	Asia/Ashgabat
 TN	+3648+01011	Africa/Tunis
-TO	-2110-17510	Pacific/Tongatapu
+TO	-210800-1751200	Pacific/Tongatapu
 TR	+4101+02858	Europe/Istanbul
-TT,AG,AI,BL,DM,GD,GP,KN,LC,MF,MS,VC,VG,VI	+1039-06131	America/Port_of_Spain
 TV	-0831+17913	Pacific/Funafuti
 TW	+2503+12130	Asia/Taipei
 UA	+5026+03031	Europe/Kiev	Ukraine (most areas)
@@ -362,7 +353,7 @@ US	+465042-1012439	America/North_Dakota/New_Salem	Central - ND (Morton rural)
 US	+471551-1014640	America/North_Dakota/Beulah	Central - ND (Mercer)
 US	+394421-1045903	America/Denver	Mountain (most areas)
 US	+433649-1161209	America/Boise	Mountain - ID (south); OR (east)
-US	+332654-1120424	America/Phoenix	MST - Arizona (except Navajo)
+US,CA	+332654-1120424	America/Phoenix	MST - Arizona (except Navajo), Creston BC
 US	+340308-1181434	America/Los_Angeles	Pacific
 US	+611305-1495401	America/Anchorage	Alaska (most areas)
 US	+581807-1342511	America/Juneau	Alaska - Juneau area