Export of internal Abseil changes.

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6fdf24a197b964f9bacbebd0ceca305aef1654fc by Shaindel Schwartz <shaindel@google.com>:

Internal change

PiperOrigin-RevId: 231627312

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65f7faf52bff01384171efb85fee159378dedf70 by CJ Johnson <johnsoncj@google.com>:

Relocates the definitions of the InputIterator-accepting parts of the InlinedVector API into the top-level. The removed functions had no other callers so there was no reason to keep the layer of indirection in the form of the function call.

PiperOrigin-RevId: 231527459

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30e105b749b5ecc50fdaf26c7da589617efce425 by CJ Johnson <johnsoncj@google.com>:

Relocates closing brace for absl namespace in InlinedVector to the correct end location

PiperOrigin-RevId: 231477871

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063c1e8b9d1f032662c46d574e20ecc357b87d0c by Eric Fiselier <ericwf@google.com>:

Cleanup std::hash probing metafunctions.

Previously there were two different ways to probe for
std::hash. One in hash.h and another in type_traits.h,
and they were both implemented differently, and neither
correctly worked around bad STL implementations.

This patch unifies the implementations into a single IsHashable trait.
It also:

* Correctly checks for old libc++ versions where this won't work.
* Avoids undefined behavior which resulted from calling std::is_constructible
  incomplete types.
* Unifies the feature test macro used in the headers and the tests.

Additionally it also slightly changes the behavior of when absl::variant
is hashable. Previously we disable hashing when std::hash<T>()(key) was
formed but when std::hash<T> couldn't be destructed. This seems wrong. If a
user provides a evil specialization of std::hash, then it's OK for variant's
hash to blow up.

PiperOrigin-RevId: 231468345

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05d75dd4b07c893de9b104731644d0d207b01253 by Abseil Team <absl-team@google.com>:

Import of CCTZ from GitHub.

PiperOrigin-RevId: 231397518

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a0ee9032f9e04039f3410ed17fcf45ae1a3868f5 by CJ Johnson <johnsoncj@google.com>:

Remove unused EnableIfAtLeastInputIterator from InlinedVector

PiperOrigin-RevId: 231348903

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4dcd4e9a6780a81d7a6974c7bf22a037e6482b49 by Abseil Team <absl-team@google.com>:

Remove unnecessary register keyword from absl/base/internal/endian.h.

PiperOrigin-RevId: 231316570

--
c8584836caa3a10f90a8604a85d4b831310b72ee by Abseil Team <absl-team@google.com>:

Fix hashtablez_sampler compilation on older Android NDK builds

PiperOrigin-RevId: 231283542
GitOrigin-RevId: 6fdf24a197b964f9bacbebd0ceca305aef1654fc
Change-Id: I185b12fb8347e3ad0ffcb2cbb83a53450e5eb938

1 files changed, 1 insertions, 0 deletions

diff --git a/absl/types/optional.h b/absl/types/optional.h
index 7677fe52c0e5..fd185f353f3e 100644
--- a/absl/types/optional.h
+++ b/absl/types/optional.h
@@ -467,6 +467,7 @@ struct optional_hash_base<T, decltype(std::hash<absl::remove_const_t<T> >()(
   using argument_type = absl::optional<T>;
   using result_type = size_t;
   size_t operator()(const absl::optional<T>& opt) const {
+    absl::type_traits_internal::AssertHashEnabled<absl::remove_const_t<T>>();
     if (opt) {
       return std::hash<absl::remove_const_t<T> >()(*opt);
     } else {