Export of internal Abseil changes

--
0f6565955231dc74ebad62ef32a18c457afa2dc7 by Abseil Team <absl-team@google.com>:

Document guarantee that we do not move from rvalue arguments if no insertion happens with absl::raw_hash_map::try_emplace, as done with std::unordered_map::try_emplace.

PiperOrigin-RevId: 264430409

--
292e6b9e08fa689e8400d7f2db94cbcab29d5889 by CJ Johnson <johnsoncj@google.com>:

Removes use of aligned_storage in FixedArray and InlinedVector in favor of aligned char buffers.

PiperOrigin-RevId: 264385559

--
aa0b19ad11ae5702022feee0e2e6434cfb28c9e9 by Derek Mauro <dmauro@google.com>:

Make the unit tests for absl::any, absl::optional, and absl::variant
no-ops when these types are just aliases for the corresponding std::
types. We have no way to fix standard library implementation bugs, so
don't bother working around them.

Also disable the corresponding exception-safety tests as well when
exceptions are not enabled.

Fixes https://github.com/abseil/abseil-cpp/pull/360

PiperOrigin-RevId: 264382050

--
65896a911f36481b89b4712c83b91c90a76b64e8 by Abseil Team <absl-team@google.com>:

Improve documentation on erase

PiperOrigin-RevId: 264381266
GitOrigin-RevId: 0f6565955231dc74ebad62ef32a18c457afa2dc7
Change-Id: I74b9bd2ddf84526014104f17e87de70bd3fe65fa

8 files changed, 43 insertions, 4 deletions

diff --git a/absl/types/BUILD.bazel b/absl/types/BUILD.bazel
index 6dd4e142..037d499a 100644
--- a/absl/types/BUILD.bazel
+++ b/absl/types/BUILD.bazel
@@ -111,6 +111,7 @@ cc_test(
     linkopts = ABSL_EXCEPTIONS_FLAG_LINKOPTS + ABSL_DEFAULT_LINKOPTS,
     deps = [
         ":any",
+        "//absl/base:config",
         "//absl/base:exception_safety_testing",
         "@com_google_googletest//:gtest_main",
     ],
@@ -240,6 +241,7 @@ cc_test(
     linkopts = ABSL_EXCEPTIONS_FLAG_LINKOPTS + ABSL_DEFAULT_LINKOPTS,
     deps = [
         ":optional",
+        "//absl/base:config",
         "//absl/base:exception_safety_testing",
         "@com_google_googletest//:gtest_main",
     ],
diff --git a/absl/types/CMakeLists.txt b/absl/types/CMakeLists.txt
index ddae7f2a..1f7fde09 100644
--- a/absl/types/CMakeLists.txt
+++ b/absl/types/CMakeLists.txt
@@ -105,6 +105,7 @@ absl_cc_test(
     ${ABSL_EXCEPTIONS_FLAG_LINKOPTS}
   DEPS
     absl::any
+    absl::config
     absl::exception_safety_testing
     gmock_main
 )
@@ -256,6 +257,7 @@ absl_cc_test(
     ${ABSL_EXCEPTIONS_FLAG_LINKOPTS}
   DEPS
     absl::optional
+    absl::config
     absl::exception_safety_testing
     gmock_main
 )
diff --git a/absl/types/any_exception_safety_test.cc b/absl/types/any_exception_safety_test.cc
index 5d7d8a5c..17d7f5d7 100644
--- a/absl/types/any_exception_safety_test.cc
+++ b/absl/types/any_exception_safety_test.cc
@@ -14,6 +14,12 @@
 
 #include "absl/types/any.h"
 
+#include "absl/base/config.h"
+
+// This test is a no-op when absl::any is an alias for std::any and when
+// exceptions are not enabled.
+#if !defined(ABSL_HAVE_STD_ANY) && defined(ABSL_HAVE_EXCEPTIONS)
+
 #include <typeinfo>
 #include <vector>
 
@@ -136,8 +142,6 @@ TEST(AnyExceptionSafety, Assignment) {
   EXPECT_TRUE(strong_empty_any_tester.Test(move));
 }
 
-// libstdc++ std::any fails this test
-#if !defined(ABSL_HAVE_STD_ANY)
 TEST(AnyExceptionSafety, Emplace) {
   auto initial_val =
       absl::any{absl::in_place_type_t<Thrower>(), 1, testing::nothrow_ctor};
@@ -163,6 +167,7 @@ TEST(AnyExceptionSafety, Emplace) {
   EXPECT_TRUE(empty_tester.Test(emp_thrower));
   EXPECT_TRUE(empty_tester.Test(emp_throwervec));
 }
-#endif  // ABSL_HAVE_STD_ANY
 
 }  // namespace
+
+#endif  // #if !defined(ABSL_HAVE_STD_ANY) && defined(ABSL_HAVE_EXCEPTIONS)
diff --git a/absl/types/any_test.cc b/absl/types/any_test.cc
index 87104721..4a848ae4 100644
--- a/absl/types/any_test.cc
+++ b/absl/types/any_test.cc
@@ -14,6 +14,9 @@
 
 #include "absl/types/any.h"
 
+// This test is a no-op when absl::any is an alias for std::any.
+#if !defined(ABSL_HAVE_STD_ANY)
+
 #include <initializer_list>
 #include <type_traits>
 #include <utility>
@@ -774,3 +777,5 @@ TEST(AnyTest, FailedEmplace) {
 }
 
 }  // namespace
+
+#endif  // #if !defined(ABSL_HAVE_STD_ANY)
diff --git a/absl/types/optional_exception_safety_test.cc b/absl/types/optional_exception_safety_test.cc
index aaf8ebcd..f99e35c0 100644
--- a/absl/types/optional_exception_safety_test.cc
+++ b/absl/types/optional_exception_safety_test.cc
@@ -14,6 +14,12 @@
 
 #include "absl/types/optional.h"
 
+#include "absl/base/config.h"
+
+// This test is a no-op when absl::optional is an alias for std::optional and
+// when exceptions are not enabled.
+#if !defined(ABSL_HAVE_STD_OPTIONAL) && defined(ABSL_HAVE_EXCEPTIONS)
+
 #include "gtest/gtest.h"
 #include "absl/base/internal/exception_safety_testing.h"
 
@@ -280,3 +286,5 @@ TEST(OptionalExceptionSafety, NothrowMoveAssign) {
 }  // namespace
 
 }  // namespace absl
+
+#endif  // #if !defined(ABSL_HAVE_STD_OPTIONAL) && defined(ABSL_HAVE_EXCEPTIONS)
diff --git a/absl/types/optional_test.cc b/absl/types/optional_test.cc
index e6a36eb8..e005affb 100644
--- a/absl/types/optional_test.cc
+++ b/absl/types/optional_test.cc
@@ -14,6 +14,9 @@
 
 #include "absl/types/optional.h"
 
+// This test is a no-op when absl::optional is an alias for std::optional.
+#if !defined(ABSL_HAVE_STD_OPTIONAL)
+
 #include <string>
 #include <type_traits>
 #include <utility>
@@ -1654,3 +1657,5 @@ TEST(optionalTest, InPlaceTSFINAEBug) {
 #endif  // !defined(__EMSCRIPTEN__)
 
 }  // namespace
+
+#endif  // #if !defined(ABSL_HAVE_STD_OPTIONAL)
diff --git a/absl/types/variant_exception_safety_test.cc b/absl/types/variant_exception_safety_test.cc
index 76beb595..fd7e6c7f 100644
--- a/absl/types/variant_exception_safety_test.cc
+++ b/absl/types/variant_exception_safety_test.cc
@@ -14,6 +14,12 @@
 
 #include "absl/types/variant.h"
 
+#include "absl/base/config.h"
+
+// This test is a no-op when absl::variant is an alias for std::variant and when
+// exceptions are not enabled.
+#if !defined(ABSL_HAVE_STD_VARIANT) && defined(ABSL_HAVE_EXCEPTIONS)
+
 #include <iostream>
 #include <memory>
 #include <utility>
@@ -21,7 +27,6 @@
 
 #include "gmock/gmock.h"
 #include "gtest/gtest.h"
-#include "absl/base/config.h"
 #include "absl/base/internal/exception_safety_testing.h"
 #include "absl/memory/memory.h"
 
@@ -521,3 +526,5 @@ TEST(VariantExceptionSafetyTest, Swap) {
 }  // namespace absl
 
 #endif  // !defined(ABSL_INTERNAL_MSVC_2017_DBG_MODE)
+
+#endif  // #if !defined(ABSL_HAVE_STD_VARIANT) && defined(ABSL_HAVE_EXCEPTIONS)
diff --git a/absl/types/variant_test.cc b/absl/types/variant_test.cc
index 85201b3e..56a6e01c 100644
--- a/absl/types/variant_test.cc
+++ b/absl/types/variant_test.cc
@@ -19,6 +19,9 @@
 
 #include "absl/types/variant.h"
 
+// This test is a no-op when absl::variant is an alias for std::variant.
+#if !defined(ABSL_HAVE_STD_VARIANT)
+
 #include <algorithm>
 #include <cstddef>
 #include <functional>
@@ -2705,3 +2708,5 @@ TEST(VariantTest, MoveCtorBug) {
 
 }  // namespace
 }  // namespace absl
+
+#endif  // #if !defined(ABSL_HAVE_STD_VARIANT)