Export of internal Abseil changes.

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5f1cf6547231f1b1daad6d1b785df6b0b999b3c9 by Samuel Benzaquen <sbenza@google.com>:

Fix uninitialized member in the `iterator` class by using a union of the two
possible states of the iterator.
This silences a Wuninitialized warning in gcc>=7.

PiperOrigin-RevId: 228175148

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98b4e3204c0ec3cfd4cb037e24d443ea4b63fc84 by CJ Johnson <johnsoncj@google.com>:

Factors out the implementation of InlinedVector::swap(...) into a private member function

PiperOrigin-RevId: 228173383

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f1432ad3a8b05285c6d55bc4754cfae765485b7f by Abseil Team <absl-team@google.com>:

Import of CCTZ from GitHub.

PiperOrigin-RevId: 227891984

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03fc00c7a4efc6000e6d9125cb2e252bffda76fe by Andy Getzendanner <durandal@google.com>:

Add a missing linebreak to a comment and markdownify two unordered lists.

PiperOrigin-RevId: 227861389

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0d66c9afba4fc9aa52e61d9fb410e165018a7b48 by Abseil Team <absl-team@google.com>:

Add an API to register a new source for the cycle clock.

PiperOrigin-RevId: 227779218

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14d3f9b70c8818b8541e5fb2f6ca4c59d479de31 by Andy Getzendanner <durandal@google.com>:

Correct a typo in a stripping marker.

PiperOrigin-RevId: 227750014

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59df88740f4e315beb57a8772f8bcf7879440c74 by Matt Kulukundis <kfm@google.com>:

Switch thread local handling to be more cross platform

PiperOrigin-RevId: 227695133

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75deed5bfcb5c42534e933f104aa7d94e11e348d by Abseil Team <absl-team@google.com>:

Rollback workaround toolchain bug for incorrect handling of thread_local in inline
functions

PiperOrigin-RevId: 227689133

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54994bf0afec026e6e0e7a199df0bbb4b7d9a4aa by Derek Mauro <dmauro@google.com>:

Add -pthread to linkopts where it actually belongs, on the library
that uses it.
Fixes https://github.com/abseil/abseil-cpp/issues/240.

PiperOrigin-RevId: 227612492

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893875f3536b7e0a1bad993aa6b2e083abb3b25a by Derek Mauro <dmauro@google.com>:

Internal change

PiperOrigin-RevId: 227582833

--
506c9b8e9002ca3389c7040473b68d4cbf94bdcc by Matt Kulukundis <kfm@google.com>:

Workaround toolchain bug for incorrect handling of thread_local in inline
functions

PiperOrigin-RevId: 227561449

--
29ee90d96dfe3114cf93f9bb92ea0cc9e768a407 by Derek Mauro <dmauro@google.com>:

Internal change

PiperOrigin-RevId: 227054634
GitOrigin-RevId: 5f1cf6547231f1b1daad6d1b785df6b0b999b3c9
Change-Id: Ibc90566d92ee6e0ad7e150f513ec7f5d22ec0a94

1 files changed, 7 insertions, 4 deletions

diff --git a/absl/container/internal/hashtablez_sampler.h b/absl/container/internal/hashtablez_sampler.h
index 4aea3ffa..c42f1842 100644
--- a/absl/container/internal/hashtablez_sampler.h
+++ b/absl/container/internal/hashtablez_sampler.h
@@ -31,6 +31,7 @@
 #include <memory>
 #include <vector>
 
+#include "absl/base/internal/per_thread_tls.h"
 #include "absl/base/optimization.h"
 #include "absl/synchronization/mutex.h"
 #include "absl/utility/utility.h"
@@ -147,14 +148,16 @@ class HashtablezInfoHandle {
 
 // Returns an RAII sampling handle that manages registration and unregistation
 // with the global sampler.
+#if ABSL_PER_THREAD_TLS == 1
+extern ABSL_PER_THREAD_TLS_KEYWORD int64_t next_sample;
+#endif  // ABSL_PER_THREAD_TLS
+
 inline HashtablezInfoHandle Sample() {
-#if ABSL_HAVE_THREAD_LOCAL
-  thread_local int64_t next_sample = 0;
-#else   // ABSL_HAVE_THREAD_LOCAL
+#if ABSL_PER_THREAD_TLS == 0
   static auto* mu = new absl::Mutex;
   static int64_t next_sample = 0;
   absl::MutexLock l(mu);
-#endif  // ABSL_HAVE_THREAD_LOCAL
+#endif  // !ABSL_HAVE_THREAD_LOCAL
 
   if (ABSL_PREDICT_TRUE(--next_sample > 0)) {
     return HashtablezInfoHandle(nullptr);