Export of internal Abseil changes

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a3e58c1870a9626039f4d178d2d599319bd9f8a8 by Matt Kulukundis <kfm@google.com>:

Allow MakeCordFromExternal to take a zero arg releaser.

PiperOrigin-RevId: 298650274

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01897c4a9bb99f3dc329a794019498ad345ddebd by Samuel Benzaquen <sbenza@google.com>:

Reduce library bloat for absl::Flag by moving the definition of base virtual functions to a .cc file.
This removes the duplicate symbols in user translation units and  has the side effect of moving the vtable definition too (re key function)

PiperOrigin-RevId: 298617920

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190f0d3782c63aed01046886d7fbc1be5bca2de9 by Derek Mauro <dmauro@google.com>:

Import GitHub #596: Unbreak stacktrace code for UWP apps

PiperOrigin-RevId: 298600834

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cd5cf6f8c87b35b85a9584e94da2a99057345b73 by Gennadiy Rozental <rogeeff@google.com>:

Use union of heap allocated pointer, one word atomic and two word atomic to represent flags value.

Any type T, which is trivially copy-able and with with sizeof(T) <= 8, will be stored in atomic int64_t.
Any type T, which is trivially copy-able and with with 8 < sizeof(T) <= 16, will be stored in atomic AlignedTwoWords.

We also introducing value storage type to distinguish these cases.

PiperOrigin-RevId: 298497200

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f8fe7bd53bfed601f002f521e34ab4bc083fc28b by Matthew Brown <matthewbr@google.com>:

Ensure a deep copy and proper equality on absl::Status::ErasePayload

PiperOrigin-RevId: 298482742

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a5c9ccddf4b04f444e3f7e27dbc14faf1fcb5373 by Gennadiy Rozental <rogeeff@google.com>:

Change ChunkIterator implementation to use fixed capacity collection of CordRep*. We can now assume that depth never exceeds 91. That makes comparison operator exception safe.

I've tested that with this CL we do not observe an overhead of chunk_end. Compiler optimized this iterator completely.

PiperOrigin-RevId: 298458472

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327ea5e8910bc388b03389c730763f9823abfce5 by Abseil Team <absl-team@google.com>:

Minor cleanups in b-tree code:
- Rename some variables: fix issues of different param names between definition/declaration, move away from `x` as a default meaningless variable name.
- Make init_leaf/init_internal be non-static methods (they already take the node as the first parameter).
- In internal_emplace/try_shrink, update root/rightmost the same way as in insert_unique/insert_multi.
- Replace a TODO with a comment.

PiperOrigin-RevId: 298432836

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8020ce9ec8558ee712d9733ae3d660ac1d3ffe1a by Abseil Team <absl-team@google.com>:

Guard against unnecessary copy in case the buffer is empty. This is important in cases were the user is explicitly tuning their chunks to match PiecewiseChunkSize().

PiperOrigin-RevId: 298366044

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89324441d1c0c697c90ba7d8fc63639805fcaa9d by Abseil Team <absl-team@google.com>:

Internal change

PiperOrigin-RevId: 298219363
GitOrigin-RevId: a3e58c1870a9626039f4d178d2d599319bd9f8a8
Change-Id: I28dffc684b6fd0292b94807b88ec6664d5d0e183

1 files changed, 103 insertions, 40 deletions

diff --git a/absl/flags/flag_test.cc b/absl/flags/flag_test.cc
index 4984d28403b2..1e01b49cc4f2 100644
--- a/absl/flags/flag_test.cc
+++ b/absl/flags/flag_test.cc
@@ -49,28 +49,6 @@ void* TestMakeDflt() {
 }
 void TestCallback() {}
 
-template <typename T>
-bool TestConstructionFor() {
-  constexpr flags::FlagHelpArg help_arg{flags::FlagHelpMsg("literal help"),
-                                        flags::FlagHelpKind::kLiteral};
-  constexpr flags::Flag<T> f1("f1", "file", help_arg, &TestMakeDflt<T>);
-  EXPECT_EQ(f1.Name(), "f1");
-  EXPECT_EQ(f1.Help(), "literal help");
-  EXPECT_EQ(f1.Filename(), "file");
-
-  ABSL_CONST_INIT static flags::Flag<T> f2(
-      "f2", "file",
-      {flags::FlagHelpMsg(&TestHelpMsg), flags::FlagHelpKind::kGenFunc},
-      &TestMakeDflt<T>);
-  flags::FlagRegistrar<T, false>(&f2).OnUpdate(TestCallback);
-
-  EXPECT_EQ(f2.Name(), "f2");
-  EXPECT_EQ(f2.Help(), "dynamic help");
-  EXPECT_EQ(f2.Filename(), "file");
-
-  return true;
-}
-
 struct UDT {
   UDT() = default;
   UDT(const UDT&) = default;
@@ -98,19 +76,103 @@ class FlagTest : public testing::Test {
   }
 };
 
+struct S1 {
+  S1() = default;
+  S1(const S1&) = default;
+  int32_t f1;
+  int64_t f2;
+};
+
+struct S2 {
+  S2() = default;
+  S2(const S2&) = default;
+  int64_t f1;
+  double f2;
+};
+
+TEST_F(FlagTest, Traits) {
+  EXPECT_EQ(flags::FlagValue::Kind<int>(),
+            flags::FlagValueStorageKind::kOneWordAtomic);
+  EXPECT_EQ(flags::FlagValue::Kind<bool>(),
+            flags::FlagValueStorageKind::kOneWordAtomic);
+  EXPECT_EQ(flags::FlagValue::Kind<double>(),
+            flags::FlagValueStorageKind::kOneWordAtomic);
+  EXPECT_EQ(flags::FlagValue::Kind<int64_t>(),
+            flags::FlagValueStorageKind::kOneWordAtomic);
+
+#if defined(ABSL_FLAGS_INTERNAL_ATOMIC_DOUBLE_WORD)
+  EXPECT_EQ(flags::FlagValue::Kind<S1>(),
+            flags::FlagValueStorageKind::kTwoWordsAtomic);
+  EXPECT_EQ(flags::FlagValue::Kind<S2>(),
+            flags::FlagValueStorageKind::kTwoWordsAtomic);
+#else
+  EXPECT_EQ(flags::FlagValue::Kind<S1>(),
+            flags::FlagValueStorageKind::kHeapAllocated);
+  EXPECT_EQ(flags::FlagValue::Kind<S2>(),
+            flags::FlagValueStorageKind::kHeapAllocated);
+#endif
+
+  EXPECT_EQ(flags::FlagValue::Kind<std::string>(),
+            flags::FlagValueStorageKind::kHeapAllocated);
+  EXPECT_EQ(flags::FlagValue::Kind<std::vector<std::string>>(),
+            flags::FlagValueStorageKind::kHeapAllocated);
+}
+
+// --------------------------------------------------------------------
+
+constexpr flags::FlagHelpArg help_arg{flags::FlagHelpMsg("literal help"),
+                                      flags::FlagHelpKind::kLiteral};
+
+using String = std::string;
+
+#define DEFINE_CONSTRUCTED_FLAG(T)                                          \
+  constexpr flags::Flag<T> f1##T("f1", "file", help_arg, &TestMakeDflt<T>); \
+  ABSL_CONST_INIT flags::Flag<T> f2##T(                                     \
+      "f2", "file",                                                         \
+      {flags::FlagHelpMsg(&TestHelpMsg), flags::FlagHelpKind::kGenFunc},    \
+      &TestMakeDflt<T>)
+
+#define TEST_CONSTRUCTED_FLAG(T) TestConstructionFor(f1##T, &f2##T);
+
+DEFINE_CONSTRUCTED_FLAG(bool);
+DEFINE_CONSTRUCTED_FLAG(int16_t);
+DEFINE_CONSTRUCTED_FLAG(uint16_t);
+DEFINE_CONSTRUCTED_FLAG(int32_t);
+DEFINE_CONSTRUCTED_FLAG(uint32_t);
+DEFINE_CONSTRUCTED_FLAG(int64_t);
+DEFINE_CONSTRUCTED_FLAG(uint64_t);
+DEFINE_CONSTRUCTED_FLAG(float);
+DEFINE_CONSTRUCTED_FLAG(double);
+DEFINE_CONSTRUCTED_FLAG(String);
+DEFINE_CONSTRUCTED_FLAG(UDT);
+
+template <typename T>
+bool TestConstructionFor(const flags::Flag<T>& f1, flags::Flag<T>* f2) {
+  EXPECT_EQ(f1.Name(), "f1");
+  EXPECT_EQ(f1.Help(), "literal help");
+  EXPECT_EQ(f1.Filename(), "file");
+
+  flags::FlagRegistrar<T, false>(f2).OnUpdate(TestCallback);
+
+  EXPECT_EQ(f2->Name(), "f2");
+  EXPECT_EQ(f2->Help(), "dynamic help");
+  EXPECT_EQ(f2->Filename(), "file");
+
+  return true;
+}
+
 TEST_F(FlagTest, TestConstruction) {
-  TestConstructionFor<bool>();
-  TestConstructionFor<int16_t>();
-  TestConstructionFor<uint16_t>();
-  TestConstructionFor<int32_t>();
-  TestConstructionFor<uint32_t>();
-  TestConstructionFor<int64_t>();
-  TestConstructionFor<uint64_t>();
-  TestConstructionFor<double>();
-  TestConstructionFor<float>();
-  TestConstructionFor<std::string>();
-
-  TestConstructionFor<UDT>();
+  TEST_CONSTRUCTED_FLAG(bool);
+  TEST_CONSTRUCTED_FLAG(int16_t);
+  TEST_CONSTRUCTED_FLAG(uint16_t);
+  TEST_CONSTRUCTED_FLAG(int32_t);
+  TEST_CONSTRUCTED_FLAG(uint32_t);
+  TEST_CONSTRUCTED_FLAG(int64_t);
+  TEST_CONSTRUCTED_FLAG(uint64_t);
+  TEST_CONSTRUCTED_FLAG(float);
+  TEST_CONSTRUCTED_FLAG(double);
+  TEST_CONSTRUCTED_FLAG(String);
+  TEST_CONSTRUCTED_FLAG(UDT);
 }
 
 // --------------------------------------------------------------------
@@ -391,17 +453,18 @@ TEST_F(FlagTest, TestCustomUDT) {
 using FlagDeathTest = FlagTest;
 
 TEST_F(FlagDeathTest, TestTypeMismatchValidations) {
-  EXPECT_DEBUG_DEATH(
-      static_cast<void>(absl::GetFlag(FLAGS_mistyped_int_flag)),
-      "Flag 'mistyped_int_flag' is defined as one type and declared "
-      "as another");
-  EXPECT_DEATH(absl::SetFlag(&FLAGS_mistyped_int_flag, 1),
+#if !defined(NDEBUG)
+  EXPECT_DEATH(static_cast<void>(absl::GetFlag(FLAGS_mistyped_int_flag)),
                "Flag 'mistyped_int_flag' is defined as one type and declared "
                "as another");
-
   EXPECT_DEATH(static_cast<void>(absl::GetFlag(FLAGS_mistyped_string_flag)),
                "Flag 'mistyped_string_flag' is defined as one type and "
                "declared as another");
+#endif
+
+  EXPECT_DEATH(absl::SetFlag(&FLAGS_mistyped_int_flag, 1),
+               "Flag 'mistyped_int_flag' is defined as one type and declared "
+               "as another");
   EXPECT_DEATH(
       absl::SetFlag(&FLAGS_mistyped_string_flag, std::vector<std::string>{}),
       "Flag 'mistyped_string_flag' is defined as one type and declared as "