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-rw-r--r--absl/base/config.h2
-rw-r--r--absl/container/btree_test.cc2
-rw-r--r--absl/container/inlined_vector_benchmark.cc37
-rw-r--r--absl/meta/type_traits_test.cc22
-rw-r--r--absl/random/internal/BUILD.bazel5
-rw-r--r--absl/random/internal/randen_hwaes.cc128
-rw-r--r--absl/random/internal/uniform_helper.h3
-rw-r--r--absl/strings/string_view.h2
-rw-r--r--absl/time/internal/cctz/src/time_zone_impl.cc13
9 files changed, 98 insertions, 116 deletions
diff --git a/absl/base/config.h b/absl/base/config.h
index 1c3cb08e746d..90d98214d09d 100644
--- a/absl/base/config.h
+++ b/absl/base/config.h
@@ -125,7 +125,7 @@
 #error ABSL_HAVE_STD_IS_TRIVIALLY_ASSIGNABLE cannot directly set
 #elif (defined(__clang__) && defined(_LIBCPP_VERSION)) ||        \
     (!defined(__clang__) && defined(__GNUC__) &&                 \
-     (__GNUC__ > 5 || (__GNUC__ == 5 && __GNUC_MINOR__ >= 1)) && \
+     (__GNUC__ > 7 || (__GNUC__ == 7 && __GNUC_MINOR__ >= 4)) && \
      (defined(_LIBCPP_VERSION) || defined(__GLIBCXX__))) ||      \
     (defined(_MSC_VER) && !defined(__NVCC__))
 #define ABSL_HAVE_STD_IS_TRIVIALLY_CONSTRUCTIBLE 1
diff --git a/absl/container/btree_test.cc b/absl/container/btree_test.cc
index a330cca32b90..3ac97f89a8b7 100644
--- a/absl/container/btree_test.cc
+++ b/absl/container/btree_test.cc
@@ -323,6 +323,7 @@ class unique_checker : public base_checker<TreeType, CheckerType> {
   unique_checker(const unique_checker &x) : super_type(x) {}
   template <class InputIterator>
   unique_checker(InputIterator b, InputIterator e) : super_type(b, e) {}
+  unique_checker& operator=(const unique_checker&) = default;
 
   // Insertion routines.
   std::pair<iterator, bool> insert(const value_type &x) {
@@ -370,6 +371,7 @@ class multi_checker : public base_checker<TreeType, CheckerType> {
   multi_checker(const multi_checker &x) : super_type(x) {}
   template <class InputIterator>
   multi_checker(InputIterator b, InputIterator e) : super_type(b, e) {}
+  multi_checker& operator=(const multi_checker&) = default;
 
   // Insertion routines.
   iterator insert(const value_type &x) {
diff --git a/absl/container/inlined_vector_benchmark.cc b/absl/container/inlined_vector_benchmark.cc
index b99bbd62544f..3f2b4ed28a57 100644
--- a/absl/container/inlined_vector_benchmark.cc
+++ b/absl/container/inlined_vector_benchmark.cc
@@ -25,42 +25,45 @@
 namespace {
 
 void BM_InlinedVectorFill(benchmark::State& state) {
+  const int len = state.range(0);
   absl::InlinedVector<int, 8> v;
-  int val = 10;
+  v.reserve(len);
   for (auto _ : state) {
+    v.resize(0);  // Use resize(0) as InlinedVector releases storage on clear().
+    for (int i = 0; i < len; ++i) {
+      v.push_back(i);
+    }
     benchmark::DoNotOptimize(v);
-    v.push_back(val);
   }
 }
-BENCHMARK(BM_InlinedVectorFill)->Range(0, 1024);
+BENCHMARK(BM_InlinedVectorFill)->Range(1, 256);
 
 void BM_InlinedVectorFillRange(benchmark::State& state) {
   const int len = state.range(0);
-  std::unique_ptr<int[]> ia(new int[len]);
-  for (int i = 0; i < len; i++) {
-    ia[i] = i;
-  }
-  auto* from = ia.get();
-  auto* to = from + len;
+  const std::vector<int> src(len, len);
+  absl::InlinedVector<int, 8> v;
+  v.reserve(len);
   for (auto _ : state) {
-    benchmark::DoNotOptimize(from);
-    benchmark::DoNotOptimize(to);
-    absl::InlinedVector<int, 8> v(from, to);
+    benchmark::DoNotOptimize(src);
+    v.assign(src.begin(), src.end());
     benchmark::DoNotOptimize(v);
   }
 }
-BENCHMARK(BM_InlinedVectorFillRange)->Range(0, 1024);
+BENCHMARK(BM_InlinedVectorFillRange)->Range(1, 256);
 
 void BM_StdVectorFill(benchmark::State& state) {
+  const int len = state.range(0);
   std::vector<int> v;
-  int val = 10;
+  v.reserve(len);
   for (auto _ : state) {
+    v.clear();
+    for (int i = 0; i < len; ++i) {
+      v.push_back(i);
+    }
     benchmark::DoNotOptimize(v);
-    benchmark::DoNotOptimize(val);
-    v.push_back(val);
   }
 }
-BENCHMARK(BM_StdVectorFill)->Range(0, 1024);
+BENCHMARK(BM_StdVectorFill)->Range(1, 256);
 
 // The purpose of the next two benchmarks is to verify that
 // absl::InlinedVector is efficient when moving is more efficent than
diff --git a/absl/meta/type_traits_test.cc b/absl/meta/type_traits_test.cc
index a7a9c5c917ff..6fbb42f82e06 100644
--- a/absl/meta/type_traits_test.cc
+++ b/absl/meta/type_traits_test.cc
@@ -546,6 +546,28 @@ TEST(TypeTraitsTest, TestTrivialDefaultCtor) {
 #endif
 }
 
+// GCC prior to 7.4 had a bug in its trivially-constructible traits
+// (https://gcc.gnu.org/bugzilla/show_bug.cgi?id=80654).
+// This test makes sure that we do not depend on the trait in these cases when
+// implementing absl triviality traits.
+
+template <class T>
+struct BadConstructors {
+  BadConstructors() { static_assert(T::value, ""); }
+
+  BadConstructors(BadConstructors&&) { static_assert(T::value, ""); }
+
+  BadConstructors(const BadConstructors&) { static_assert(T::value, ""); }
+};
+
+TEST(TypeTraitsTest, TestTrivialityBadConstructors) {
+  using BadType = BadConstructors<int>;
+
+  EXPECT_FALSE(absl::is_trivially_default_constructible<BadType>::value);
+  EXPECT_FALSE(absl::is_trivially_move_constructible<BadType>::value);
+  EXPECT_FALSE(absl::is_trivially_copy_constructible<BadType>::value);
+}
+
 TEST(TypeTraitsTest, TestTrivialMoveCtor) {
   // Verify that arithmetic types and pointers have trivial move
   // constructors.
diff --git a/absl/random/internal/BUILD.bazel b/absl/random/internal/BUILD.bazel
index 7416e93642bd..d9581d00e587 100644
--- a/absl/random/internal/BUILD.bazel
+++ b/absl/random/internal/BUILD.bazel
@@ -306,7 +306,10 @@ cc_library(
     # anyway and thus there wouldn't be any gain from using it as a module.
     features = ["-header_modules"],
     linkopts = ABSL_DEFAULT_LINKOPTS,
-    deps = [":platform"],
+    deps = [
+        ":platform",
+        "//absl/base:core_headers",
+    ],
 )
 
 cc_binary(
diff --git a/absl/random/internal/randen_hwaes.cc b/absl/random/internal/randen_hwaes.cc
index 6b82d1d07ad8..7d5b2b74128b 100644
--- a/absl/random/internal/randen_hwaes.cc
+++ b/absl/random/internal/randen_hwaes.cc
@@ -22,39 +22,9 @@
 #include <cstdint>
 #include <cstring>
 
+#include "absl/base/attributes.h"
 #include "absl/random/internal/platform.h"
 
-// ABSL_HAVE_ATTRIBUTE
-#if !defined(ABSL_HAVE_ATTRIBUTE)
-#ifdef __has_attribute
-#define ABSL_HAVE_ATTRIBUTE(x) __has_attribute(x)
-#else
-#define ABSL_HAVE_ATTRIBUTE(x) 0
-#endif
-#endif
-
-#if ABSL_HAVE_ATTRIBUTE(always_inline) || \
-    (defined(__GNUC__) && !defined(__clang__))
-#define ABSL_RANDOM_INTERNAL_ATTRIBUTE_ALWAYS_INLINE \
-  __attribute__((always_inline))
-#elif defined(_MSC_VER)
-// We can achieve something similar to attribute((always_inline)) with MSVC by
-// using the __forceinline keyword, however this is not perfect. MSVC is
-// much less aggressive about inlining, and even with the __forceinline keyword.
-#define ABSL_RANDOM_INTERNAL_ATTRIBUTE_ALWAYS_INLINE __forceinline
-#else
-#define ABSL_RANDOM_INTERNAL_ATTRIBUTE_ALWAYS_INLINE
-#endif
-
-// ABSL_ATTRIBUTE_FLATTEN enables much more aggressive inlining within
-// the indicated function.
-#undef ABSL_ATTRIBUTE_FLATTEN
-#if ABSL_HAVE_ATTRIBUTE(flatten) || (defined(__GNUC__) && !defined(__clang__))
-#define ABSL_ATTRIBUTE_FLATTEN __attribute__((flatten))
-#else
-#define ABSL_ATTRIBUTE_FLATTEN
-#endif
-
 // ABSL_RANDEN_HWAES_IMPL indicates whether this file will contain
 // a hardware accelerated implementation of randen, or whether it
 // will contain stubs that exit the process.
@@ -146,18 +116,6 @@ void RandenHwAes::Generate(const void*, void*) {
 
 #include "absl/random/internal/randen_traits.h"
 
-// ABSL_FUNCTION_ALIGN32 defines a 32-byte alignment attribute
-// for the functions in this file.
-//
-// NOTE: Determine whether we actually have any wins from ALIGN32
-// using microbenchmarks. If not, remove.
-#undef ABSL_FUNCTION_ALIGN32
-#if ABSL_HAVE_ATTRIBUTE(aligned) || (defined(__GNUC__) && !defined(__clang__))
-#define ABSL_FUNCTION_ALIGN32 __attribute__((aligned(32)))
-#else
-#define ABSL_FUNCTION_ALIGN32
-#endif
-
 // TARGET_CRYPTO defines a crypto attribute for each architecture.
 //
 // NOTE: Evaluate whether we should eliminate ABSL_TARGET_CRYPTO.
@@ -191,8 +149,7 @@ using Vector128 = __vector unsigned long long;  // NOLINT(runtime/int)
 
 namespace {
 
-inline ABSL_TARGET_CRYPTO ABSL_RANDOM_INTERNAL_ATTRIBUTE_ALWAYS_INLINE Vector128
-ReverseBytes(const Vector128& v) {
+inline ABSL_TARGET_CRYPTO Vector128 ReverseBytes(const Vector128& v) {
   // Reverses the bytes of the vector.
   const __vector unsigned char perm = {15, 14, 13, 12, 11, 10, 9, 8,
                                        7,  6,  5,  4,  3,  2,  1, 0};
@@ -202,26 +159,26 @@ ReverseBytes(const Vector128& v) {
 // WARNING: these load/store in native byte order. It is OK to load and then
 // store an unchanged vector, but interpreting the bits as a number or input
 // to AES will have undefined results.
-inline ABSL_TARGET_CRYPTO ABSL_RANDOM_INTERNAL_ATTRIBUTE_ALWAYS_INLINE Vector128
+inline ABSL_TARGET_CRYPTO Vector128
 Vector128Load(const void* ABSL_RANDOM_INTERNAL_RESTRICT from) {
   return vec_vsx_ld(0, reinterpret_cast<const Vector128*>(from));
 }
 
-inline ABSL_TARGET_CRYPTO ABSL_RANDOM_INTERNAL_ATTRIBUTE_ALWAYS_INLINE void
-Vector128Store(const Vector128& v, void* ABSL_RANDOM_INTERNAL_RESTRICT to) {
+inline ABSL_TARGET_CRYPTO void Vector128Store(
+    const Vector128& v, void* ABSL_RANDOM_INTERNAL_RESTRICT to) {
   vec_vsx_st(v, 0, reinterpret_cast<Vector128*>(to));
 }
 
 // One round of AES. "round_key" is a public constant for breaking the
 // symmetry of AES (ensures previously equal columns differ afterwards).
-inline ABSL_TARGET_CRYPTO ABSL_RANDOM_INTERNAL_ATTRIBUTE_ALWAYS_INLINE Vector128
-AesRound(const Vector128& state, const Vector128& round_key) {
+inline ABSL_TARGET_CRYPTO Vector128 AesRound(const Vector128& state,
+                                             const Vector128& round_key) {
   return Vector128(__builtin_crypto_vcipher(state, round_key));
 }
 
 // Enables native loads in the round loop by pre-swapping.
-inline ABSL_TARGET_CRYPTO ABSL_RANDOM_INTERNAL_ATTRIBUTE_ALWAYS_INLINE void
-SwapEndian(uint64_t* ABSL_RANDOM_INTERNAL_RESTRICT state) {
+inline ABSL_TARGET_CRYPTO void SwapEndian(
+    uint64_t* ABSL_RANDOM_INTERNAL_RESTRICT state) {
   using absl::random_internal::RandenTraits;
   constexpr size_t kLanes = 2;
   constexpr size_t kFeistelBlocks = RandenTraits::kFeistelBlocks;
@@ -273,20 +230,20 @@ using Vector128 = uint8x16_t;
 
 namespace {
 
-inline ABSL_TARGET_CRYPTO ABSL_RANDOM_INTERNAL_ATTRIBUTE_ALWAYS_INLINE Vector128
+inline ABSL_TARGET_CRYPTO Vector128
 Vector128Load(const void* ABSL_RANDOM_INTERNAL_RESTRICT from) {
   return vld1q_u8(reinterpret_cast<const uint8_t*>(from));
 }
 
-inline ABSL_TARGET_CRYPTO ABSL_RANDOM_INTERNAL_ATTRIBUTE_ALWAYS_INLINE void
-Vector128Store(const Vector128& v, void* ABSL_RANDOM_INTERNAL_RESTRICT to) {
+inline ABSL_TARGET_CRYPTO void Vector128Store(
+    const Vector128& v, void* ABSL_RANDOM_INTERNAL_RESTRICT to) {
   vst1q_u8(reinterpret_cast<uint8_t*>(to), v);
 }
 
 // One round of AES. "round_key" is a public constant for breaking the
 // symmetry of AES (ensures previously equal columns differ afterwards).
-inline ABSL_TARGET_CRYPTO ABSL_RANDOM_INTERNAL_ATTRIBUTE_ALWAYS_INLINE Vector128
-AesRound(const Vector128& state, const Vector128& round_key) {
+inline ABSL_TARGET_CRYPTO Vector128 AesRound(const Vector128& state,
+                                             const Vector128& round_key) {
   // It is important to always use the full round function - omitting the
   // final MixColumns reduces security [https://eprint.iacr.org/2010/041.pdf]
   // and does not help because we never decrypt.
@@ -297,8 +254,8 @@ AesRound(const Vector128& state, const Vector128& round_key) {
   return vaesmcq_u8(vaeseq_u8(state, uint8x16_t{})) ^ round_key;
 }
 
-inline ABSL_TARGET_CRYPTO ABSL_RANDOM_INTERNAL_ATTRIBUTE_ALWAYS_INLINE void
-SwapEndian(uint64_t* ABSL_RANDOM_INTERNAL_RESTRICT) {}
+inline ABSL_TARGET_CRYPTO void SwapEndian(
+    uint64_t* ABSL_RANDOM_INTERNAL_RESTRICT) {}
 
 }  // namespace
 
@@ -313,16 +270,11 @@ namespace {
 class Vector128 {
  public:
   // Convert from/to intrinsics.
-  inline ABSL_RANDOM_INTERNAL_ATTRIBUTE_ALWAYS_INLINE explicit Vector128(
-      const __m128i& Vector128)
-      : data_(Vector128) {}
+  inline explicit Vector128(const __m128i& Vector128) : data_(Vector128) {}
 
-  inline ABSL_RANDOM_INTERNAL_ATTRIBUTE_ALWAYS_INLINE __m128i data() const {
-    return data_;
-  }
+  inline __m128i data() const { return data_; }
 
-  inline ABSL_RANDOM_INTERNAL_ATTRIBUTE_ALWAYS_INLINE Vector128& operator^=(
-      const Vector128& other) {
+  inline Vector128& operator^=(const Vector128& other) {
     data_ = _mm_xor_si128(data_, other.data());
     return *this;
   }
@@ -331,29 +283,29 @@ class Vector128 {
   __m128i data_;
 };
 
-inline ABSL_TARGET_CRYPTO ABSL_RANDOM_INTERNAL_ATTRIBUTE_ALWAYS_INLINE Vector128
+inline ABSL_TARGET_CRYPTO Vector128
 Vector128Load(const void* ABSL_RANDOM_INTERNAL_RESTRICT from) {
   return Vector128(_mm_load_si128(reinterpret_cast<const __m128i*>(from)));
 }
 
-inline ABSL_TARGET_CRYPTO ABSL_RANDOM_INTERNAL_ATTRIBUTE_ALWAYS_INLINE void
-Vector128Store(const Vector128& v, void* ABSL_RANDOM_INTERNAL_RESTRICT to) {
+inline ABSL_TARGET_CRYPTO void Vector128Store(
+    const Vector128& v, void* ABSL_RANDOM_INTERNAL_RESTRICT to) {
   _mm_store_si128(reinterpret_cast<__m128i * ABSL_RANDOM_INTERNAL_RESTRICT>(to),
                   v.data());
 }
 
 // One round of AES. "round_key" is a public constant for breaking the
 // symmetry of AES (ensures previously equal columns differ afterwards).
-inline ABSL_TARGET_CRYPTO ABSL_RANDOM_INTERNAL_ATTRIBUTE_ALWAYS_INLINE Vector128
-AesRound(const Vector128& state, const Vector128& round_key) {
+inline ABSL_TARGET_CRYPTO Vector128 AesRound(const Vector128& state,
+                                             const Vector128& round_key) {
   // It is important to always use the full round function - omitting the
   // final MixColumns reduces security [https://eprint.iacr.org/2010/041.pdf]
   // and does not help because we never decrypt.
   return Vector128(_mm_aesenc_si128(state.data(), round_key.data()));
 }
 
-inline ABSL_TARGET_CRYPTO ABSL_RANDOM_INTERNAL_ATTRIBUTE_ALWAYS_INLINE void
-SwapEndian(uint64_t* ABSL_RANDOM_INTERNAL_RESTRICT) {}
+inline ABSL_TARGET_CRYPTO void SwapEndian(
+    uint64_t* ABSL_RANDOM_INTERNAL_RESTRICT) {}
 
 }  // namespace
 
@@ -450,8 +402,8 @@ constexpr size_t kLanes = 2;
 
 // Block shuffles applies a shuffle to the entire state between AES rounds.
 // Improved odd-even shuffle from "New criterion for diffusion property".
-inline ABSL_RANDOM_INTERNAL_ATTRIBUTE_ALWAYS_INLINE ABSL_TARGET_CRYPTO void
-BlockShuffle(uint64_t* ABSL_RANDOM_INTERNAL_RESTRICT state) {
+inline ABSL_TARGET_CRYPTO void BlockShuffle(
+    uint64_t* ABSL_RANDOM_INTERNAL_RESTRICT state) {
   static_assert(kFeistelBlocks == 16, "Expecting 16 FeistelBlocks.");
 
   constexpr size_t shuffle[kFeistelBlocks] = {7,  2, 13, 4,  11, 8,  3, 6,
@@ -499,10 +451,9 @@ BlockShuffle(uint64_t* ABSL_RANDOM_INTERNAL_RESTRICT state) {
 // per 16 bytes (vs. 10 for AES-CTR). Computing eight round functions in
 // parallel hides the 7-cycle AESNI latency on HSW. Note that the Feistel
 // XORs are 'free' (included in the second AES instruction).
-inline ABSL_RANDOM_INTERNAL_ATTRIBUTE_ALWAYS_INLINE ABSL_TARGET_CRYPTO const
-    u64x2*
-    FeistelRound(uint64_t* ABSL_RANDOM_INTERNAL_RESTRICT state,
-                 const u64x2* ABSL_RANDOM_INTERNAL_RESTRICT keys) {
+inline ABSL_TARGET_CRYPTO const u64x2* FeistelRound(
+    uint64_t* ABSL_RANDOM_INTERNAL_RESTRICT state,
+    const u64x2* ABSL_RANDOM_INTERNAL_RESTRICT keys) {
   static_assert(kFeistelBlocks == 16, "Expecting 16 FeistelBlocks.");
 
   // MSVC does a horrible job at unrolling loops.
@@ -561,9 +512,9 @@ inline ABSL_RANDOM_INTERNAL_ATTRIBUTE_ALWAYS_INLINE ABSL_TARGET_CRYPTO const
 // Indistinguishable from ideal by chosen-ciphertext adversaries using less than
 // 2^64 queries if the round function is a PRF. This is similar to the b=8 case
 // of Simpira v2, but more efficient than its generic construction for b=16.
-inline ABSL_RANDOM_INTERNAL_ATTRIBUTE_ALWAYS_INLINE ABSL_TARGET_CRYPTO void
-Permute(const void* ABSL_RANDOM_INTERNAL_RESTRICT keys,
-        uint64_t* ABSL_RANDOM_INTERNAL_RESTRICT state) {
+inline ABSL_TARGET_CRYPTO void Permute(
+    const void* ABSL_RANDOM_INTERNAL_RESTRICT keys,
+    uint64_t* ABSL_RANDOM_INTERNAL_RESTRICT state) {
   const u64x2* ABSL_RANDOM_INTERNAL_RESTRICT keys128 =
       static_cast<const u64x2*>(keys);
 
@@ -584,16 +535,15 @@ namespace random_internal {
 
 bool HasRandenHwAesImplementation() { return true; }
 
-const void* ABSL_TARGET_CRYPTO ABSL_FUNCTION_ALIGN32 ABSL_ATTRIBUTE_FLATTEN
-RandenHwAes::GetKeys() {
+const void* ABSL_TARGET_CRYPTO RandenHwAes::GetKeys() {
   // Round keys for one AES per Feistel round and branch.
   // The canonical implementation uses first digits of Pi.
   return round_keys;
 }
 
 // NOLINTNEXTLINE
-void ABSL_TARGET_CRYPTO ABSL_FUNCTION_ALIGN32 ABSL_ATTRIBUTE_FLATTEN
-RandenHwAes::Absorb(const void* seed_void, void* state_void) {
+void ABSL_TARGET_CRYPTO RandenHwAes::Absorb(const void* seed_void,
+                                            void* state_void) {
   uint64_t* ABSL_RANDOM_INTERNAL_RESTRICT state =
       reinterpret_cast<uint64_t*>(state_void);
   const uint64_t* ABSL_RANDOM_INTERNAL_RESTRICT seed =
@@ -669,8 +619,8 @@ RandenHwAes::Absorb(const void* seed_void, void* state_void) {
 }
 
 // NOLINTNEXTLINE
-void ABSL_TARGET_CRYPTO ABSL_FUNCTION_ALIGN32 ABSL_ATTRIBUTE_FLATTEN
-RandenHwAes::Generate(const void* keys, void* state_void) {
+void ABSL_TARGET_CRYPTO RandenHwAes::Generate(const void* keys,
+                                              void* state_void) {
   static_assert(kCapacityBytes == sizeof(Vector128), "Capacity mismatch");
 
   uint64_t* ABSL_RANDOM_INTERNAL_RESTRICT state =
diff --git a/absl/random/internal/uniform_helper.h b/absl/random/internal/uniform_helper.h
index 21646489643a..ebcc3744b188 100644
--- a/absl/random/internal/uniform_helper.h
+++ b/absl/random/internal/uniform_helper.h
@@ -35,9 +35,6 @@ struct IntervalClosedClosedT {};
 struct IntervalClosedOpenT {};
 struct IntervalOpenClosedT {};
 struct IntervalOpenOpenT {};
-}  // namespace random_internal
-
-namespace random_internal {
 
 // The functions
 //    uniform_lower_bound(tag, a, b)
diff --git a/absl/strings/string_view.h b/absl/strings/string_view.h
index 25a4d1edeafe..a1b5a17b52b3 100644
--- a/absl/strings/string_view.h
+++ b/absl/strings/string_view.h
@@ -342,7 +342,7 @@ class string_view {
     size_type rlen = (std::min)(length_ - pos, n);
     if (rlen > 0) {
       const char* start = ptr_ + pos;
-      std::copy(start, start + rlen, buf);
+      traits_type::copy(buf, start, rlen);
     }
     return rlen;
   }
diff --git a/absl/time/internal/cctz/src/time_zone_impl.cc b/absl/time/internal/cctz/src/time_zone_impl.cc
index 3cbc674653dd..a26151d3e917 100644
--- a/absl/time/internal/cctz/src/time_zone_impl.cc
+++ b/absl/time/internal/cctz/src/time_zone_impl.cc
@@ -33,7 +33,12 @@ using TimeZoneImplByName =
 TimeZoneImplByName* time_zone_map = nullptr;
 
 // Mutual exclusion for time_zone_map.
-std::mutex time_zone_mutex;
+std::mutex& TimeZoneMutex() {
+  // This mutex is intentionally "leaked" to avoid the static deinitialization
+  // order fiasco (std::mutex's destructor is not trivial on many platforms).
+  static std::mutex* time_zone_mutex = new std::mutex;
+  return *time_zone_mutex;
+}
 
 }  // namespace
 
@@ -54,7 +59,7 @@ bool time_zone::Impl::LoadTimeZone(const std::string& name, time_zone* tz) {
   // Then check, under a shared lock, whether the time zone has already
   // been loaded. This is the common path. TODO: Move to shared_mutex.
   {
-    std::lock_guard<std::mutex> lock(time_zone_mutex);
+    std::lock_guard<std::mutex> lock(TimeZoneMutex());
     if (time_zone_map != nullptr) {
       TimeZoneImplByName::const_iterator itr = time_zone_map->find(name);
       if (itr != time_zone_map->end()) {
@@ -65,7 +70,7 @@ bool time_zone::Impl::LoadTimeZone(const std::string& name, time_zone* tz) {
   }
 
   // Now check again, under an exclusive lock.
-  std::lock_guard<std::mutex> lock(time_zone_mutex);
+  std::lock_guard<std::mutex> lock(TimeZoneMutex());
   if (time_zone_map == nullptr) time_zone_map = new TimeZoneImplByName;
   const Impl*& impl = (*time_zone_map)[name];
   if (impl == nullptr) {
@@ -84,7 +89,7 @@ bool time_zone::Impl::LoadTimeZone(const std::string& name, time_zone* tz) {
 }
 
 void time_zone::Impl::ClearTimeZoneMapTestOnly() {
-  std::lock_guard<std::mutex> lock(time_zone_mutex);
+  std::lock_guard<std::mutex> lock(TimeZoneMutex());
   if (time_zone_map != nullptr) {
     // Existing time_zone::Impl* entries are in the wild, so we simply
     // leak them.  Future requests will result in reloading the data.