Export of internal Abseil changes.

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28b634d3e8e879546e20006b81086a2b02390f1d by Abseil Team <absl-team@google.com>:

Indicate Solaris / Illumos has mmap support
https://github.com/abseil/abseil-cpp/pull/139
This change is **untested** as Abseil does not officially support Solaris/Illumos.

PiperOrigin-RevId: 205094615

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3c4cc80abcd91c6cd88209a61b50936d1c498bac by Xiaoyi Zhang <zhangxy@google.com>:

Make is_trivially_copy_assignable work with reference types.

PiperOrigin-RevId: 204982099

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98c6658b3d6cd5eddba9f498747dc84c172ffe05 by Abseil Team <absl-team@google.com>:

Fix typo in comments for c_mismatch.

PiperOrigin-RevId: 204962537

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deef8b23585f7831d67c1d4b1c9ef7f3e30d9028 by Matt Kulukundis <kfm@google.com>:

Internal change

PiperOrigin-RevId: 204956873
GitOrigin-RevId: 28b634d3e8e879546e20006b81086a2b02390f1d
Change-Id: I1da029f8cb83d83ee5a05f3b0c6a07bc3dd5368e

absl/algorithm/container.h

@@ -314,7 +314,7 @@ container_algorithm_internal::ContainerDifferenceType<const C> c_count_if(
 
 // c_mismatch()
 //
-// Container-based version of the <algorithm> `std::mismatchf()` function to
+// Container-based version of the <algorithm> `std::mismatch()` function to
 // return the first element where two ordered containers differ.
 template <typename C1, typename C2>
 container_algorithm_internal::ContainerIterPairType<C1, C2>

absl/container/inlined_vector_test.cc

@@ -1788,5 +1788,4 @@ TEST(AllocatorSupportTest, SizeAllocConstructor) {
     EXPECT_THAT(v, AllOf(SizeIs(len), Each(0)));
   }
 }
-
 }  // anonymous namespace

absl/meta/type_traits.h

@@ -263,8 +263,9 @@ struct is_trivially_copy_constructible
 // `is_trivially_assignable<T&, const T&>`.
 template <typename T>
 struct is_trivially_copy_assignable
-    : std::integral_constant<bool, __has_trivial_assign(T) &&
-                                   std::is_copy_assignable<T>::value> {
+    : std::integral_constant<
+          bool, __has_trivial_assign(typename std::remove_reference<T>::type) &&
+                    std::is_copy_assignable<T>::value> {
 #ifdef ABSL_HAVE_STD_IS_TRIVIALLY_ASSIGNABLE
  private:
   static constexpr bool compliant =

absl/meta/type_traits_test.cc

@@ -528,6 +528,10 @@ TEST(TypeTraitsTest, TestTrivialCopyAssign) {
   // Verify that arrays are not trivially copy assignable
   using int10 = int[10];
   EXPECT_FALSE(absl::is_trivially_copy_assignable<int10>::value);
+
+  // Verify that references are handled correctly
+  EXPECT_TRUE(absl::is_trivially_copy_assignable<Trivial&&>::value);
+  EXPECT_TRUE(absl::is_trivially_copy_assignable<Trivial&>::value);
 }
 
 #define ABSL_INTERNAL_EXPECT_ALIAS_EQUIVALENCE(trait_name, ...)          \