Export of internal Abseil changes

-- 587e6db882749fa7faa12815e614afab04d218b9 by Derek Mauro <dmauro@google.com>: Use attribute detection for other sanitizer related attributes PiperOrigin-RevId: 324077073 -- 3ee55e4935b4235516b1fcac3c55945e510f7afc by Evan Brown <ezb@google.com>: Simplify CordRepExternal allocation/deallocation. I think this can save some memory when `Releaser` is empty and when on platforms where alignof(CordRepExternal) < (default `::operator new` alignment). We no longer need the API requirement that alignof(Releaser) <= (default `::operator new` alignment). Also remove another static_assert from a TODO in cord_internal.h and fix some warnings about calling std::move on a forwarding reference. PiperOrigin-RevId: 324053720 -- 9fc78436565eb3b204d4aa425ee3773354392f45 by Derek Mauro <dmauro@google.com>: Use auto-detected sanitizer attributes for ASAN, MSAN, and TSAN builds PiperOrigin-RevId: 323831461 GitOrigin-RevId: 587e6db882749fa7faa12815e614afab04d218b9 Change-Id: Ie0e4a2846d7f66988a2d81a5e50721b62fdb3d6d
2026-06-04 12:07:05 +08:00 · 2020-07-30 13:58:50 -07:00
parent 82302f1e05
commit 184cf25241
39 changed files with 180 additions and 235 deletions
--- a/absl/base/BUILD.bazel
+++ b/absl/base/BUILD.bazel
@@ -415,6 +415,7 @@ cc_library(
    deps = [
        ":base",
        ":base_internal",
+        ":config",
        ":core_headers",
        "//absl/synchronization",
        "@com_google_googletest//:gtest",
@@ -431,6 +432,7 @@ cc_test(
    deps = [
        ":base",
        ":base_internal",
+        ":config",
        ":core_headers",
        "//absl/synchronization",
        "@com_google_googletest//:gtest_main",
--- a/absl/base/CMakeLists.txt
+++ b/absl/base/CMakeLists.txt
@@ -384,6 +384,7 @@ absl_cc_library(
    ${ABSL_TEST_COPTS}
  DEPS
    absl::base
+    absl::config
    absl::base_internal
    absl::core_headers
    absl::synchronization
@@ -402,6 +403,7 @@ absl_cc_test(
  DEPS
    absl::base
    absl::base_internal
+    absl::config
    absl::core_headers
    absl::synchronization
    gtest_main
--- a/absl/base/attributes.h
+++ b/absl/base/attributes.h
@@ -32,34 +32,12 @@
 // of them are not supported in older version of Clang. Thus, we check
 // `__has_attribute()` first. If the check fails, we check if we are on GCC and
 // assume the attribute exists on GCC (which is verified on GCC 4.7).
-//
-// -----------------------------------------------------------------------------
-// Sanitizer Attributes
-// -----------------------------------------------------------------------------
-//
-// Sanitizer-related attributes are not "defined" in this file (and indeed
-// are not defined as such in any file). To utilize the following
-// sanitizer-related attributes within your builds, define the following macros
-// within your build using a `-D` flag, along with the given value for
-// `-fsanitize`:
-//
-//   * `ADDRESS_SANITIZER` + `-fsanitize=address` (Clang, GCC 4.8)
-//   * `MEMORY_SANITIZER` + `-fsanitize=memory` (Clang-only)
-//   * `THREAD_SANITIZER` + `-fsanitize=thread` (Clang, GCC 4.8+)
-//   * `UNDEFINED_BEHAVIOR_SANITIZER` + `-fsanitize=undefined` (Clang, GCC 4.9+)
-//   * `CONTROL_FLOW_INTEGRITY` + `-fsanitize=cfi` (Clang-only)
-//
-// Example:
-//
-//   // Enable branches in the Abseil code that are tagged for ASan:
-//   $ bazel build --copt=-DADDRESS_SANITIZER --copt=-fsanitize=address
-//     --linkopt=-fsanitize=address *target*
-//
-// Since these macro names are only supported by GCC and Clang, we only check
-// for `__GNUC__` (GCC or Clang) and the above macros.
+
 #ifndef ABSL_BASE_ATTRIBUTES_H_
 #define ABSL_BASE_ATTRIBUTES_H_

+#include "absl/base/config.h"
+
 // ABSL_HAVE_ATTRIBUTE
 //
 // A function-like feature checking macro that is a wrapper around
@@ -234,7 +212,7 @@
 // out of bounds or does other scary things with memory.
 // NOTE: GCC supports AddressSanitizer(asan) since 4.8.
 // https://gcc.gnu.org/gcc-4.8/changes.html
-#if defined(__GNUC__)
+#if ABSL_HAVE_ATTRIBUTE(no_sanitize_address)
 #define ABSL_ATTRIBUTE_NO_SANITIZE_ADDRESS __attribute__((no_sanitize_address))
 #else
 #define ABSL_ATTRIBUTE_NO_SANITIZE_ADDRESS
@@ -242,13 +220,13 @@

 // ABSL_ATTRIBUTE_NO_SANITIZE_MEMORY
 //
-// Tells the  MemorySanitizer to relax the handling of a given function. All
-// "Use of uninitialized value" warnings from such functions will be suppressed,
-// and all values loaded from memory will be considered fully initialized.
-// This attribute is similar to the ADDRESS_SANITIZER attribute above, but deals
-// with initialized-ness rather than addressability issues.
+// Tells the MemorySanitizer to relax the handling of a given function. All "Use
+// of uninitialized value" warnings from such functions will be suppressed, and
+// all values loaded from memory will be considered fully initialized.  This
+// attribute is similar to the ABSL_ATTRIBUTE_NO_SANITIZE_ADDRESS attribute
+// above, but deals with initialized-ness rather than addressability issues.
 // NOTE: MemorySanitizer(msan) is supported by Clang but not GCC.
-#if defined(__clang__)
+#if ABSL_HAVE_ATTRIBUTE(no_sanitize_memory)
 #define ABSL_ATTRIBUTE_NO_SANITIZE_MEMORY __attribute__((no_sanitize_memory))
 #else
 #define ABSL_ATTRIBUTE_NO_SANITIZE_MEMORY
@@ -259,7 +237,7 @@
 // Tells the ThreadSanitizer to not instrument a given function.
 // NOTE: GCC supports ThreadSanitizer(tsan) since 4.8.
 // https://gcc.gnu.org/gcc-4.8/changes.html
-#if defined(__GNUC__)
+#if ABSL_HAVE_ATTRIBUTE(no_sanitize_thread)
 #define ABSL_ATTRIBUTE_NO_SANITIZE_THREAD __attribute__((no_sanitize_thread))
 #else
 #define ABSL_ATTRIBUTE_NO_SANITIZE_THREAD
@@ -271,8 +249,10 @@
 // where certain behavior (eg. division by zero) is being used intentionally.
 // NOTE: GCC supports UndefinedBehaviorSanitizer(ubsan) since 4.9.
 // https://gcc.gnu.org/gcc-4.9/changes.html
-#if defined(__GNUC__) && \
-    (defined(UNDEFINED_BEHAVIOR_SANITIZER) || defined(ADDRESS_SANITIZER))
+#if ABSL_HAVE_ATTRIBUTE(no_sanitize_undefined)
+#define ABSL_ATTRIBUTE_NO_SANITIZE_UNDEFINED \
+  __attribute__((no_sanitize_undefined))
+#elif ABSL_HAVE_ATTRIBUTE(no_sanitize)
 #define ABSL_ATTRIBUTE_NO_SANITIZE_UNDEFINED \
  __attribute__((no_sanitize("undefined")))
 #else
@@ -283,7 +263,7 @@
 //
 // Tells the ControlFlowIntegrity sanitizer to not instrument a given function.
 // See https://clang.llvm.org/docs/ControlFlowIntegrity.html for details.
-#if defined(__GNUC__) && defined(CONTROL_FLOW_INTEGRITY)
+#if ABSL_HAVE_ATTRIBUTE(no_sanitize)
 #define ABSL_ATTRIBUTE_NO_SANITIZE_CFI __attribute__((no_sanitize("cfi")))
 #else
 #define ABSL_ATTRIBUTE_NO_SANITIZE_CFI
@@ -293,7 +273,7 @@
 //
 // Tells the SafeStack to not instrument a given function.
 // See https://clang.llvm.org/docs/SafeStack.html for details.
-#if defined(__GNUC__) && defined(SAFESTACK_SANITIZER)
+#if ABSL_HAVE_ATTRIBUTE(no_sanitize)
 #define ABSL_ATTRIBUTE_NO_SANITIZE_SAFESTACK \
  __attribute__((no_sanitize("safe-stack")))
 #else
--- a/absl/base/internal/dynamic_annotations.h
+++ b/absl/base/internal/dynamic_annotations.h
@@ -91,12 +91,9 @@
 #endif

 // Memory annotations are also made available to LLVM's Memory Sanitizer
-#if defined(MEMORY_SANITIZER) && defined(__has_feature) && \
-    !defined(__native_client__)
-#if __has_feature(memory_sanitizer)
+#if defined(ABSL_HAVE_MEMORY_SANITIZER) && !defined(__native_client__)
 #define ABSL_INTERNAL_MEMORY_ANNOTATIONS_ENABLED 1
 #endif
-#endif

 #ifndef ABSL_INTERNAL_MEMORY_ANNOTATIONS_ENABLED
 #define ABSL_INTERNAL_MEMORY_ANNOTATIONS_ENABLED 0
@@ -162,7 +159,7 @@
  ABSL_INTERNAL_GLOBAL_SCOPED(AnnotateRWLockCreate)(__FILE__, __LINE__, lock)

 // Report that a linker initialized lock has been created at address `lock`.
-#ifdef THREAD_SANITIZER
+#ifdef ABSL_HAVE_THREAD_SANITIZER
 #define ANNOTATE_RWLOCK_CREATE_STATIC(lock)               \
  ABSL_INTERNAL_GLOBAL_SCOPED(AnnotateRWLockCreateStatic) \
  (__FILE__, __LINE__, lock)
@@ -367,7 +364,7 @@
 // -------------------------------------------------------------------------
 // Address sanitizer annotations

-#ifdef ADDRESS_SANITIZER
+#ifdef ABSL_HAVE_ADDRESS_SANITIZER
 // Describe the current state of a contiguous container such as e.g.
 // std::vector or std::string. For more details see
 // sanitizer/common_interface_defs.h, which is provided by the compiler.
@@ -385,7 +382,7 @@
 #define ANNOTATE_CONTIGUOUS_CONTAINER(beg, end, old_mid, new_mid)
 #define ADDRESS_SANITIZER_REDZONE(name) static_assert(true, "")

-#endif  // ADDRESS_SANITIZER
+#endif  // ABSL_HAVE_ADDRESS_SANITIZER

 // -------------------------------------------------------------------------
 // Undefine the macros intended only for this file.
--- a/absl/base/internal/tsan_mutex_interface.h
+++ b/absl/base/internal/tsan_mutex_interface.h
@@ -19,6 +19,8 @@
 #ifndef ABSL_BASE_INTERNAL_TSAN_MUTEX_INTERFACE_H_
 #define ABSL_BASE_INTERNAL_TSAN_MUTEX_INTERFACE_H_

+#include "absl/base/config.h"
+
 // ABSL_INTERNAL_HAVE_TSAN_INTERFACE
 // Macro intended only for internal use.
 //
@@ -28,7 +30,7 @@
 #error "ABSL_INTERNAL_HAVE_TSAN_INTERFACE cannot be directly set."
 #endif

-#if defined(THREAD_SANITIZER) && defined(__has_include)
+#if defined(ABSL_HAVE_THREAD_SANITIZER) && defined(__has_include)
 #if __has_include(<sanitizer/tsan_interface.h>)
 #define ABSL_INTERNAL_HAVE_TSAN_INTERFACE 1
 #endif
--- a/absl/base/internal/unaligned_access.h
+++ b/absl/base/internal/unaligned_access.h
@@ -32,8 +32,8 @@
 // (namespaces, inline) which are absent or incompatible in C.
 #if defined(__cplusplus)

-#if defined(ADDRESS_SANITIZER) || defined(THREAD_SANITIZER) ||\
-    defined(MEMORY_SANITIZER)
+#if defined(ABSL_HAVE_ADDRESS_SANITIZER) || \
+    defined(ABSL_HAVE_THREAD_SANITIZER) || defined(ABSL_HAVE_MEMORY_SANITIZER)
 // Consider we have an unaligned load/store of 4 bytes from address 0x...05.
 // AddressSanitizer will treat it as a 3-byte access to the range 05:07 and
 // will miss a bug if 08 is the first unaddressable byte.
--- a/absl/base/spinlock_test_common.cc
+++ b/absl/base/spinlock_test_common.cc
@@ -25,6 +25,7 @@

 #include "gtest/gtest.h"
 #include "absl/base/attributes.h"
+#include "absl/base/config.h"
 #include "absl/base/internal/low_level_scheduling.h"
 #include "absl/base/internal/scheduling_mode.h"
 #include "absl/base/internal/spinlock.h"
@@ -104,7 +105,7 @@ static void ThreadedTest(SpinLock* spinlock) {
  }
 }

-#ifndef THREAD_SANITIZER
+#ifndef ABSL_HAVE_THREAD_SANITIZER
 static_assert(std::is_trivially_destructible<SpinLock>(), "");
 #endif

--- a/absl/container/BUILD.bazel
+++ b/absl/container/BUILD.bazel
@@ -60,6 +60,7 @@ cc_library(
    deps = [
        ":compressed_tuple",
        "//absl/algorithm",
+        "//absl/base:config",
        "//absl/base:core_headers",
        "//absl/base:dynamic_annotations",
        "//absl/base:throw_delegate",
@@ -368,6 +369,7 @@ cc_library(
    copts = ABSL_DEFAULT_COPTS,
    linkopts = ABSL_DEFAULT_LINKOPTS,
    deps = [
+        "//absl/base:config",
        "//absl/memory",
        "//absl/meta:type_traits",
        "//absl/utility",
@@ -620,6 +622,7 @@ cc_test(
        ":hashtable_debug",
        ":raw_hash_set",
        "//absl/base",
+        "//absl/base:config",
        "//absl/base:core_headers",
        "//absl/base:raw_logging_internal",
        "//absl/strings",
@@ -647,6 +650,7 @@ cc_library(
    copts = ABSL_DEFAULT_COPTS,
    linkopts = ABSL_DEFAULT_LINKOPTS,
    deps = [
+        "//absl/base:config",
        "//absl/base:core_headers",
        "//absl/meta:type_traits",
        "//absl/strings",
@@ -665,6 +669,7 @@ cc_test(
    visibility = ["//visibility:private"],
    deps = [
        ":layout",
+        "//absl/base:config",
        "//absl/base:core_headers",
        "//absl/base:raw_logging_internal",
        "//absl/types:span",
--- a/absl/container/CMakeLists.txt
+++ b/absl/container/CMakeLists.txt
@@ -131,6 +131,7 @@ absl_cc_library(
  DEPS
    absl::compressed_tuple
    absl::algorithm
+    absl::config
    absl::core_headers
    absl::dynamic_annotations
    absl::throw_delegate
@@ -423,6 +424,7 @@ absl_cc_library(
  COPTS
    ${ABSL_DEFAULT_COPTS}
  DEPS
+    absl::config
    absl::memory
    absl::type_traits
    absl::utility
@@ -696,6 +698,7 @@ absl_cc_test(
    absl::hashtable_debug
    absl::raw_hash_set
    absl::base
+    absl::config
    absl::core_headers
    absl::raw_logging_internal
    absl::strings
@@ -724,6 +727,7 @@ absl_cc_library(
  COPTS
    ${ABSL_DEFAULT_COPTS}
  DEPS
+    absl::config
    absl::core_headers
    absl::meta
    absl::strings
@@ -741,6 +745,7 @@ absl_cc_test(
    ${ABSL_TEST_COPTS}
  DEPS
    absl::layout
+    absl::config
    absl::core_headers
    absl::raw_logging_internal
    absl::span
--- a/absl/container/fixed_array.h
+++ b/absl/container/fixed_array.h
@@ -41,6 +41,7 @@
 #include <type_traits>

 #include "absl/algorithm/algorithm.h"
+#include "absl/base/config.h"
 #include "absl/base/dynamic_annotations.h"
 #include "absl/base/internal/throw_delegate.h"
 #include "absl/base/macros.h"
@@ -422,10 +423,10 @@ class FixedArray {
    void AnnotateConstruct(size_type n);
    void AnnotateDestruct(size_type n);

-#ifdef ADDRESS_SANITIZER
+#ifdef ABSL_HAVE_ADDRESS_SANITIZER
    void* RedzoneBegin() { return &redzone_begin_; }
    void* RedzoneEnd() { return &redzone_end_ + 1; }
-#endif  // ADDRESS_SANITIZER
+#endif  // ABSL_HAVE_ADDRESS_SANITIZER

   private:
    ABSL_ADDRESS_SANITIZER_REDZONE(redzone_begin_);
@@ -503,26 +504,26 @@ constexpr typename FixedArray<T, N, A>::size_type
 template <typename T, size_t N, typename A>
 void FixedArray<T, N, A>::NonEmptyInlinedStorage::AnnotateConstruct(
    typename FixedArray<T, N, A>::size_type n) {
-#ifdef ADDRESS_SANITIZER
+#ifdef ABSL_HAVE_ADDRESS_SANITIZER
  if (!n) return;
  ABSL_ANNOTATE_CONTIGUOUS_CONTAINER(data(), RedzoneEnd(), RedzoneEnd(),
                                     data() + n);
  ABSL_ANNOTATE_CONTIGUOUS_CONTAINER(RedzoneBegin(), data(), data(),
                                     RedzoneBegin());
-#endif                   // ADDRESS_SANITIZER
+#endif  // ABSL_HAVE_ADDRESS_SANITIZER
  static_cast<void>(n);  // Mark used when not in asan mode
 }

 template <typename T, size_t N, typename A>
 void FixedArray<T, N, A>::NonEmptyInlinedStorage::AnnotateDestruct(
    typename FixedArray<T, N, A>::size_type n) {
-#ifdef ADDRESS_SANITIZER
+#ifdef ABSL_HAVE_ADDRESS_SANITIZER
  if (!n) return;
  ABSL_ANNOTATE_CONTIGUOUS_CONTAINER(data(), RedzoneEnd(), data() + n,
                                     RedzoneEnd());
  ABSL_ANNOTATE_CONTIGUOUS_CONTAINER(RedzoneBegin(), data(), RedzoneBegin(),
                                     data());
-#endif                   // ADDRESS_SANITIZER
+#endif  // ABSL_HAVE_ADDRESS_SANITIZER
  static_cast<void>(n);  // Mark used when not in asan mode
 }
 ABSL_NAMESPACE_END
--- a/absl/container/fixed_array_test.cc
+++ b/absl/container/fixed_array_test.cc
@@ -27,6 +27,7 @@

 #include "gmock/gmock.h"
 #include "gtest/gtest.h"
+#include "absl/base/config.h"
 #include "absl/base/internal/exception_testing.h"
 #include "absl/base/options.h"
 #include "absl/container/internal/counting_allocator.h"
@@ -767,7 +768,7 @@ TEST(AllocatorSupportTest, SizeValAllocConstructor) {
  }
 }

-#ifdef ADDRESS_SANITIZER
+#ifdef ABSL_HAVE_ADDRESS_SANITIZER
 TEST(FixedArrayTest, AddressSanitizerAnnotations1) {
  absl::FixedArray<int, 32> a(10);
  int* raw = a.data();
@@ -814,7 +815,7 @@ TEST(FixedArrayTest, AddressSanitizerAnnotations4) {
  // so reading raw[21] should still trigger the correct warning.
  EXPECT_DEATH_IF_SUPPORTED(raw[21] = ThreeInts(), "container-overflow");
 }
-#endif  // ADDRESS_SANITIZER
+#endif  // ABSL_HAVE_ADDRESS_SANITIZER

 TEST(FixedArrayTest, AbslHashValueWorks) {
  using V = absl::FixedArray<int>;
--- a/absl/container/internal/container_memory.h
+++ b/absl/container/internal/container_memory.h
@@ -15,14 +15,6 @@
 #ifndef ABSL_CONTAINER_INTERNAL_CONTAINER_MEMORY_H_
 #define ABSL_CONTAINER_INTERNAL_CONTAINER_MEMORY_H_

-#ifdef ADDRESS_SANITIZER
-#include <sanitizer/asan_interface.h>
-#endif
-
-#ifdef MEMORY_SANITIZER
-#include <sanitizer/msan_interface.h>
-#endif
-
 #include <cassert>
 #include <cstddef>
 #include <memory>
@@ -30,10 +22,19 @@
 #include <type_traits>
 #include <utility>

+#include "absl/base/config.h"
 #include "absl/memory/memory.h"
 #include "absl/meta/type_traits.h"
 #include "absl/utility/utility.h"

+#ifdef ABSL_HAVE_ADDRESS_SANITIZER
+#include <sanitizer/asan_interface.h>
+#endif
+
+#ifdef ABSL_HAVE_MEMORY_SANITIZER
+#include <sanitizer/msan_interface.h>
+#endif
+
 namespace absl {
 ABSL_NAMESPACE_BEGIN
 namespace container_internal {
@@ -209,10 +210,10 @@ DecomposeValue(F&& f, Arg&& arg) {

 // Helper functions for asan and msan.
 inline void SanitizerPoisonMemoryRegion(const void* m, size_t s) {
-#ifdef ADDRESS_SANITIZER
+#ifdef ABSL_HAVE_ADDRESS_SANITIZER
  ASAN_POISON_MEMORY_REGION(m, s);
 #endif
-#ifdef MEMORY_SANITIZER
+#ifdef ABSL_HAVE_MEMORY_SANITIZER
  __msan_poison(m, s);
 #endif
  (void)m;
@@ -220,10 +221,10 @@ inline void SanitizerPoisonMemoryRegion(const void* m, size_t s) {
 }

 inline void SanitizerUnpoisonMemoryRegion(const void* m, size_t s) {
-#ifdef ADDRESS_SANITIZER
+#ifdef ABSL_HAVE_ADDRESS_SANITIZER
  ASAN_UNPOISON_MEMORY_REGION(m, s);
 #endif
-#ifdef MEMORY_SANITIZER
+#ifdef ABSL_HAVE_MEMORY_SANITIZER
  __msan_unpoison(m, s);
 #endif
  (void)m;
--- a/absl/container/internal/layout.h
+++ b/absl/container/internal/layout.h
@@ -163,6 +163,7 @@
 #include <assert.h>
 #include <stddef.h>
 #include <stdint.h>
+
 #include <ostream>
 #include <string>
 #include <tuple>
@@ -170,15 +171,16 @@
 #include <typeinfo>
 #include <utility>

-#ifdef ADDRESS_SANITIZER
-#include <sanitizer/asan_interface.h>
-#endif
-
+#include "absl/base/config.h"
 #include "absl/meta/type_traits.h"
 #include "absl/strings/str_cat.h"
 #include "absl/types/span.h"
 #include "absl/utility/utility.h"

+#ifdef ABSL_HAVE_ADDRESS_SANITIZER
+#include <sanitizer/asan_interface.h>
+#endif
+
 #if defined(__GXX_RTTI)
 #define ABSL_INTERNAL_HAS_CXA_DEMANGLE
 #endif
@@ -614,7 +616,7 @@ class LayoutImpl<std::tuple<Elements...>, absl::index_sequence<SizeSeq...>,
  void PoisonPadding(const Char* p) const {
    static_assert(N < NumOffsets, "Index out of bounds");
    (void)p;
-#ifdef ADDRESS_SANITIZER
+#ifdef ABSL_HAVE_ADDRESS_SANITIZER
    PoisonPadding<Char, N - 1>(p);
    // The `if` is an optimization. It doesn't affect the observable behaviour.
    if (ElementAlignment<N - 1>::value % ElementAlignment<N>::value) {
--- a/absl/container/internal/layout_test.cc
+++ b/absl/container/internal/layout_test.cc
@@ -17,6 +17,7 @@
 // We need ::max_align_t because some libstdc++ versions don't provide
 // std::max_align_t
 #include <stddef.h>
+
 #include <cstdint>
 #include <memory>
 #include <sstream>
@@ -24,6 +25,7 @@

 #include "gmock/gmock.h"
 #include "gtest/gtest.h"
+#include "absl/base/config.h"
 #include "absl/base/internal/raw_logging.h"
 #include "absl/types/span.h"

@@ -1314,7 +1316,7 @@ struct Region {
 };

 void ExpectRegionPoisoned(const unsigned char* p, size_t n, bool poisoned) {
-#ifdef ADDRESS_SANITIZER
+#ifdef ABSL_HAVE_ADDRESS_SANITIZER
  for (size_t i = 0; i != n; ++i) {
    EXPECT_EQ(poisoned, __asan_address_is_poisoned(p + i));
  }
--- a/absl/container/internal/raw_hash_set_test.cc
+++ b/absl/container/internal/raw_hash_set_test.cc
@@ -26,6 +26,7 @@
 #include "gmock/gmock.h"
 #include "gtest/gtest.h"
 #include "absl/base/attributes.h"
+#include "absl/base/config.h"
 #include "absl/base/internal/cycleclock.h"
 #include "absl/base/internal/raw_logging.h"
 #include "absl/container/internal/container_memory.h"
@@ -1839,7 +1840,7 @@ TEST(RawHashSamplerTest, DoNotSampleCustomAllocators) {
              0.00, 0.001);
 }

-#ifdef ADDRESS_SANITIZER
+#ifdef ABSL_HAVE_ADDRESS_SANITIZER
 TEST(Sanitizer, PoisoningUnused) {
  IntTable t;
  t.reserve(5);
@@ -1863,7 +1864,7 @@ TEST(Sanitizer, PoisoningOnErase) {
  t.erase(0);
  EXPECT_TRUE(__asan_address_is_poisoned(&v));
 }
-#endif  // ADDRESS_SANITIZER
+#endif  // ABSL_HAVE_ADDRESS_SANITIZER

 }  // namespace
 }  // namespace container_internal
--- a/absl/debugging/BUILD.bazel
+++ b/absl/debugging/BUILD.bazel
@@ -97,6 +97,7 @@ cc_test(
        ":stack_consumption",
        ":symbolize",
        "//absl/base",
+        "//absl/base:config",
        "//absl/base:core_headers",
        "//absl/base:raw_logging_internal",
        "//absl/memory",
@@ -204,6 +205,7 @@ cc_test(
    deps = [
        ":demangle_internal",
        ":stack_consumption",
+        "//absl/base:config",
        "//absl/base:core_headers",
        "//absl/base:raw_logging_internal",
        "//absl/memory",
--- a/absl/debugging/CMakeLists.txt
+++ b/absl/debugging/CMakeLists.txt
@@ -82,6 +82,7 @@ absl_cc_test(
    absl::stack_consumption
    absl::symbolize
    absl::base
+    absl::config
    absl::core_headers
    absl::memory
    absl::raw_logging_internal
@@ -189,6 +190,7 @@ absl_cc_test(
  DEPS
    absl::demangle_internal
    absl::stack_consumption
+    absl::config
    absl::core_headers
    absl::memory
    absl::raw_logging_internal
--- a/absl/debugging/failure_signal_handler.cc
+++ b/absl/debugging/failure_signal_handler.cc
@@ -136,8 +136,8 @@ static bool SetupAlternateStackOnce() {
  const size_t page_mask = sysconf(_SC_PAGESIZE) - 1;
 #endif
  size_t stack_size = (std::max(SIGSTKSZ, 65536) + page_mask) & ~page_mask;
-#if defined(ADDRESS_SANITIZER) || defined(MEMORY_SANITIZER) || \
-    defined(THREAD_SANITIZER)
+#if defined(ABSL_HAVE_ADDRESS_SANITIZER) || \
+    defined(ABSL_HAVE_MEMORY_SANITIZER) || defined(ABSL_HAVE_THREAD_SANITIZER)
  // Account for sanitizer instrumentation requiring additional stack space.
  stack_size *= 5;
 #endif
--- a/absl/debugging/internal/demangle_test.cc
+++ b/absl/debugging/internal/demangle_test.cc
@@ -18,6 +18,7 @@
 #include <string>

 #include "gtest/gtest.h"
+#include "absl/base/config.h"
 #include "absl/base/internal/raw_logging.h"
 #include "absl/debugging/internal/stack_consumption.h"
 #include "absl/memory/memory.h"
@@ -82,9 +83,10 @@ TEST(Demangle, Clones) {
 // Tests that verify that Demangle footprint is within some limit.
 // They are not to be run under sanitizers as the sanitizers increase
 // stack consumption by about 4x.
-#if defined(ABSL_INTERNAL_HAVE_DEBUGGING_STACK_CONSUMPTION) &&   \
-    !defined(ADDRESS_SANITIZER) && !defined(MEMORY_SANITIZER) && \
-    !defined(THREAD_SANITIZER)
+#if defined(ABSL_INTERNAL_HAVE_DEBUGGING_STACK_CONSUMPTION) && \
+    !defined(ABSL_HAVE_ADDRESS_SANITIZER) &&                   \
+    !defined(ABSL_HAVE_MEMORY_SANITIZER) &&                    \
+    !defined(ABSL_HAVE_THREAD_SANITIZER)

 static const char *g_mangled;
 static char g_demangle_buffer[4096];
--- a/absl/debugging/symbolize_test.cc
+++ b/absl/debugging/symbolize_test.cc
@@ -27,6 +27,7 @@
 #include "gtest/gtest.h"
 #include "absl/base/attributes.h"
 #include "absl/base/casts.h"
+#include "absl/base/config.h"
 #include "absl/base/internal/per_thread_tls.h"
 #include "absl/base/internal/raw_logging.h"
 #include "absl/base/optimization.h"
@@ -220,8 +221,8 @@ static const char *SymbolizeStackConsumption(void *pc, int *stack_consumed) {
 static int GetStackConsumptionUpperLimit() {
  // Symbolize stack consumption should be within 2kB.
  int stack_consumption_upper_limit = 2048;
-#if defined(ADDRESS_SANITIZER) || defined(MEMORY_SANITIZER) || \
-    defined(THREAD_SANITIZER)
+#if defined(ABSL_HAVE_ADDRESS_SANITIZER) || \
+    defined(ABSL_HAVE_MEMORY_SANITIZER) || defined(ABSL_HAVE_THREAD_SANITIZER)
  // Account for sanitizer instrumentation requiring additional stack space.
  stack_consumption_upper_limit *= 5;
 #endif
--- a/absl/strings/BUILD.bazel
+++ b/absl/strings/BUILD.bazel
@@ -258,6 +258,8 @@ cc_library(
    visibility = ["//visibility:private"],
    deps = [
        ":strings",
+        "//absl/base:base_internal",
+        "//absl/container:compressed_tuple",
        "//absl/meta:type_traits",
    ],
 )
@@ -277,7 +279,6 @@ cc_library(
        ":str_format",
        ":strings",
        "//absl/base",
-        "//absl/base:base_internal",
        "//absl/base:core_headers",
        "//absl/base:endian",
        "//absl/base:raw_logging_internal",
--- a/absl/strings/CMakeLists.txt
+++ b/absl/strings/CMakeLists.txt
@@ -548,6 +548,7 @@ absl_cc_library(
  DEPS
    absl::base
    absl::base_internal
+    absl::compressed_tuple
    absl::core_headers
    absl::endian
    absl::fixed_array
--- a/absl/strings/cord.cc
+++ b/absl/strings/cord.cc
@@ -61,48 +61,6 @@ enum CordRepKind {
  FLAT          = 3,
 };

-namespace {
-
-// Type used with std::allocator for allocating and deallocating
-// `CordRepExternal`. std::allocator is used because it opaquely handles the
-// different new / delete overloads available on a given platform.
-struct alignas(absl::cord_internal::ExternalRepAlignment()) ExternalAllocType {
-  unsigned char value[absl::cord_internal::ExternalRepAlignment()];
-};
-
-// Returns the number of objects to pass in to std::allocator<ExternalAllocType>
-// allocate() and deallocate() to create enough room for `CordRepExternal` with
-// `releaser_size` bytes on the end.
-constexpr size_t GetExternalAllocNumObjects(size_t releaser_size) {
-  // Be sure to round up since `releaser_size` could be smaller than
-  // `sizeof(ExternalAllocType)`.
-  return (sizeof(CordRepExternal) + releaser_size + sizeof(ExternalAllocType) -
-          1) /
-         sizeof(ExternalAllocType);
-}
-
-// Allocates enough memory for `CordRepExternal` and a releaser with size
-// `releaser_size` bytes.
-void* AllocateExternal(size_t releaser_size) {
-  return std::allocator<ExternalAllocType>().allocate(
-      GetExternalAllocNumObjects(releaser_size));
-}
-
-// Deallocates the memory for a `CordRepExternal` assuming it was allocated with
-// a releaser of given size and alignment.
-void DeallocateExternal(CordRepExternal* p, size_t releaser_size) {
-  std::allocator<ExternalAllocType>().deallocate(
-      reinterpret_cast<ExternalAllocType*>(p),
-      GetExternalAllocNumObjects(releaser_size));
-}
-
-// Returns a pointer to the type erased releaser for the given CordRepExternal.
-void* GetExternalReleaser(CordRepExternal* rep) {
-  return rep + 1;
-}
-
-}  // namespace
-
 namespace cord_internal {

 inline CordRepConcat* CordRep::concat() {
@@ -304,11 +262,7 @@ static void UnrefInternal(CordRep* rep) {
      }
    } else if (rep->tag == EXTERNAL) {
      CordRepExternal* rep_external = rep->external();
-      absl::string_view data(rep_external->base, rep->length);
-      void* releaser = GetExternalReleaser(rep_external);
-      size_t releaser_size = rep_external->releaser_invoker(releaser, data);
-      rep_external->~CordRepExternal();
-      DeallocateExternal(rep_external, releaser_size);
+      rep_external->releaser_invoker(rep_external);
      rep = nullptr;
    } else if (rep->tag == SUBSTRING) {
      CordRepSubstring* rep_substring = rep->substring();
@@ -458,18 +412,12 @@ static CordRep* NewTree(const char* data,

 namespace cord_internal {

-ExternalRepReleaserPair NewExternalWithUninitializedReleaser(
-    absl::string_view data, ExternalReleaserInvoker invoker,
-    size_t releaser_size) {
+void InitializeCordRepExternal(absl::string_view data, CordRepExternal* rep) {
  assert(!data.empty());
-
-  void* raw_rep = AllocateExternal(releaser_size);
-  auto* rep = new (raw_rep) CordRepExternal();
  rep->length = data.size();
  rep->tag = EXTERNAL;
  rep->base = data.data();
-  rep->releaser_invoker = invoker;
-  return {VerifyTree(rep), GetExternalReleaser(rep)};
+  VerifyTree(rep);
 }

 }  // namespace cord_internal
@@ -721,12 +669,12 @@ Cord::Cord(T&& src) {
      std::string data;
    };
    const absl::string_view original_data = src;
-    CordRepExternal* rep =
-        static_cast<CordRepExternal*>(absl::cord_internal::NewExternalRep(
-            original_data, StringReleaser{std::move(src)}));
+    auto* rep = static_cast<
+        ::absl::cord_internal::CordRepExternalImpl<StringReleaser>*>(
+        absl::cord_internal::NewExternalRep(
+            original_data, StringReleaser{std::forward<T>(src)}));
    // Moving src may have invalidated its data pointer, so adjust it.
-    rep->base =
-        static_cast<StringReleaser*>(GetExternalReleaser(rep))->data.data();
+    rep->base = rep->template get<0>().data.data();
    contents_.set_tree(rep);
  }
 }
@@ -775,7 +723,7 @@ Cord& Cord::operator=(T&& src) {
  if (src.size() <= kMaxBytesToCopy) {
    *this = absl::string_view(src);
  } else {
-    *this = Cord(std::move(src));
+    *this = Cord(std::forward<T>(src));
  }
  return *this;
 }
@@ -898,7 +846,7 @@ void Cord::Append(T&& src) {
  if (src.size() <= kMaxBytesToCopy) {
    Append(absl::string_view(src));
  } else {
-    Append(Cord(std::move(src)));
+    Append(Cord(std::forward<T>(src)));
  }
 }

@@ -938,7 +886,7 @@ inline void Cord::Prepend(T&& src) {
  if (src.size() <= kMaxBytesToCopy) {
    Prepend(absl::string_view(src));
  } else {
-    Prepend(Cord(std::move(src)));
+    Prepend(Cord(std::forward<T>(src)));
  }
 }

--- a/absl/strings/cord.h
+++ b/absl/strings/cord.h
@@ -71,7 +71,6 @@
 #include <type_traits>

 #include "absl/base/internal/endian.h"
-#include "absl/base/internal/invoke.h"
 #include "absl/base/internal/per_thread_tls.h"
 #include "absl/base/macros.h"
 #include "absl/base/port.h"
@@ -173,10 +172,6 @@ class Cord {
  //
  //   * be move constructible
  //   * support `void operator()(absl::string_view) const` or `void operator()`
-  //   * not have alignment requirement greater than what is guaranteed by
-  //     `::operator new`. This alignment is dictated by
-  //     `alignof(std::max_align_t)` (pre-C++17 code) or
-  //     `__STDCPP_DEFAULT_NEW_ALIGNMENT__` (C++17 code).
  //
  // Example:
  //
@@ -842,47 +837,15 @@ inline void SmallMemmove(char* dst, const char* src, size_t n,
  }
 }

-struct ExternalRepReleaserPair {
-  CordRep* rep;
-  void* releaser_address;
-};
-
-// Allocates a new external `CordRep` and returns a pointer to it and a pointer
-// to `releaser_size` bytes where the desired releaser can be constructed.
+// Does non-template-specific `CordRepExternal` initialization.
 // Expects `data` to be non-empty.
-ExternalRepReleaserPair NewExternalWithUninitializedReleaser(
-    absl::string_view data, ExternalReleaserInvoker invoker,
-    size_t releaser_size);
-
-struct Rank1 {};
-struct Rank0 : Rank1 {};
-
-template <typename Releaser, typename = ::absl::base_internal::invoke_result_t<
-                                 Releaser, absl::string_view>>
-void InvokeReleaser(Rank0, Releaser&& releaser, absl::string_view data) {
-  ::absl::base_internal::invoke(std::forward<Releaser>(releaser), data);
-}
-
-template <typename Releaser,
-          typename = ::absl::base_internal::invoke_result_t<Releaser>>
-void InvokeReleaser(Rank1, Releaser&& releaser, absl::string_view) {
-  ::absl::base_internal::invoke(std::forward<Releaser>(releaser));
-}
+void InitializeCordRepExternal(absl::string_view data, CordRepExternal* rep);

 // Creates a new `CordRep` that owns `data` and `releaser` and returns a pointer
 // to it, or `nullptr` if `data` was empty.
 template <typename Releaser>
 // NOLINTNEXTLINE - suppress clang-tidy raw pointer return.
 CordRep* NewExternalRep(absl::string_view data, Releaser&& releaser) {
-  static_assert(
-#if defined(__STDCPP_DEFAULT_NEW_ALIGNMENT__)
-      alignof(Releaser) <= __STDCPP_DEFAULT_NEW_ALIGNMENT__,
-#else
-      alignof(Releaser) <= alignof(max_align_t),
-#endif
-      "Releasers with alignment requirement greater than what is returned by "
-      "default `::operator new()` are not supported.");
-
  using ReleaserType = absl::decay_t<Releaser>;
  if (data.empty()) {
    // Never create empty external nodes.
@@ -891,18 +854,10 @@ CordRep* NewExternalRep(absl::string_view data, Releaser&& releaser) {
    return nullptr;
  }

-  auto releaser_invoker = [](void* type_erased_releaser, absl::string_view d) {
-    auto* my_releaser = static_cast<ReleaserType*>(type_erased_releaser);
-    InvokeReleaser(Rank0{}, std::move(*my_releaser), d);
-    my_releaser->~ReleaserType();
-    return sizeof(Releaser);
-  };
-
-  ExternalRepReleaserPair external = NewExternalWithUninitializedReleaser(
-      data, releaser_invoker, sizeof(releaser));
-  ::new (external.releaser_address)
-      ReleaserType(std::forward<Releaser>(releaser));
-  return external.rep;
+  CordRepExternal* rep = new CordRepExternalImpl<ReleaserType>(
+      std::forward<Releaser>(releaser), 0);
+  InitializeCordRepExternal(data, rep);
+  return rep;
 }

 // Overload for function reference types that dispatches using a function
--- a/absl/strings/internal/cord_internal.h
+++ b/absl/strings/internal/cord_internal.h
@@ -21,6 +21,8 @@
 #include <cstdint>
 #include <type_traits>

+#include "absl/base/internal/invoke.h"
+#include "absl/container/internal/compressed_tuple.h"
 #include "absl/meta/type_traits.h"
 #include "absl/strings/string_view.h"

@@ -114,35 +116,56 @@ struct CordRepSubstring : public CordRep {
  CordRep* child;
 };

-// TODO(strel): replace the following logic (and related functions in cord.cc)
-// with container_internal::Layout.
-
-// Alignment requirement for CordRepExternal so that the type erased releaser
-// will be stored at a suitably aligned address.
-constexpr size_t ExternalRepAlignment() {
-#if defined(__STDCPP_DEFAULT_NEW_ALIGNMENT__)
-  return __STDCPP_DEFAULT_NEW_ALIGNMENT__;
-#else
-  return alignof(max_align_t);
-#endif
-}
-
-// Type for function pointer that will invoke and destroy the type-erased
-// releaser function object. Accepts a pointer to the releaser and the
-// `string_view` that were passed in to `NewExternalRep` below. The return value
-// is the size of the `Releaser` type.
-using ExternalReleaserInvoker = size_t (*)(void*, absl::string_view);
+// Type for function pointer that will invoke the releaser function and also
+// delete the `CordRepExternalImpl` corresponding to the passed in
+// `CordRepExternal`.
+using ExternalReleaserInvoker = void (*)(CordRepExternal*);

 // External CordReps are allocated together with a type erased releaser. The
 // releaser is stored in the memory directly following the CordRepExternal.
-struct alignas(ExternalRepAlignment()) CordRepExternal : public CordRep {
+struct CordRepExternal : public CordRep {
  const char* base;
  // Pointer to function that knows how to call and destroy the releaser.
  ExternalReleaserInvoker releaser_invoker;
 };

-// TODO(strel): look into removing, it doesn't seem like anything relies on this
-static_assert(sizeof(CordRepConcat) == sizeof(CordRepSubstring), "");
+struct Rank1 {};
+struct Rank0 : Rank1 {};
+
+template <typename Releaser, typename = ::absl::base_internal::invoke_result_t<
+                                 Releaser, absl::string_view>>
+void InvokeReleaser(Rank0, Releaser&& releaser, absl::string_view data) {
+  ::absl::base_internal::invoke(std::forward<Releaser>(releaser), data);
+}
+
+template <typename Releaser,
+          typename = ::absl::base_internal::invoke_result_t<Releaser>>
+void InvokeReleaser(Rank1, Releaser&& releaser, absl::string_view) {
+  ::absl::base_internal::invoke(std::forward<Releaser>(releaser));
+}
+
+// We use CompressedTuple so that we can benefit from EBCO.
+template <typename Releaser>
+struct CordRepExternalImpl
+    : public CordRepExternal,
+      public ::absl::container_internal::CompressedTuple<Releaser> {
+  // The extra int arg is so that we can avoid interfering with copy/move
+  // constructors while still benefitting from perfect forwarding.
+  template <typename T>
+  CordRepExternalImpl(T&& releaser, int)
+      : CordRepExternalImpl::CompressedTuple(std::forward<T>(releaser)) {
+    this->releaser_invoker = &Release;
+  }
+
+  ~CordRepExternalImpl() {
+    InvokeReleaser(Rank0{}, std::move(this->template get<0>()),
+                   absl::string_view(base, length));
+  }
+
+  static void Release(CordRepExternal* rep) {
+    delete static_cast<CordRepExternalImpl*>(rep);
+  }
+};

 }  // namespace cord_internal
 ABSL_NAMESPACE_END
--- a/absl/strings/string_view_test.cc
+++ b/absl/strings/string_view_test.cc
@@ -1177,7 +1177,7 @@ TEST(FindOneCharTest, EdgeCases) {
  EXPECT_EQ(absl::string_view::npos, a.rfind('x'));
 }

-#ifndef THREAD_SANITIZER  // Allocates too much memory for tsan.
+#ifndef ABSL_HAVE_THREAD_SANITIZER  // Allocates too much memory for tsan.
 TEST(HugeStringView, TwoPointTwoGB) {
  if (sizeof(size_t) <= 4)
    return;
@@ -1191,7 +1191,7 @@ TEST(HugeStringView, TwoPointTwoGB) {
  sp.remove_suffix(2);
  EXPECT_EQ(size - 1 - 2, sp.length());
 }
-#endif  // THREAD_SANITIZER
+#endif  // ABSL_HAVE_THREAD_SANITIZER

 #if !defined(NDEBUG) && !defined(ABSL_USES_STD_STRING_VIEW)
 TEST(NonNegativeLenTest, NonNegativeLen) {
--- a/absl/synchronization/BUILD.bazel
+++ b/absl/synchronization/BUILD.bazel
@@ -190,6 +190,7 @@ cc_test(
        ":synchronization",
        ":thread_pool",
        "//absl/base",
+        "//absl/base:config",
        "//absl/base:core_headers",
        "//absl/base:raw_logging_internal",
        "//absl/memory",
@@ -211,6 +212,7 @@ cc_library(
        ":synchronization",
        ":thread_pool",
        "//absl/base",
+        "//absl/base:config",
        "@com_github_google_benchmark//:benchmark_main",
    ],
    alwayslink = 1,
@@ -249,6 +251,7 @@ cc_library(
    deps = [
        ":synchronization",
        "//absl/base",
+        "//absl/base:config",
        "//absl/strings",
        "//absl/time",
        "@com_google_googletest//:gtest",
--- a/absl/synchronization/CMakeLists.txt
+++ b/absl/synchronization/CMakeLists.txt
@@ -149,6 +149,7 @@ absl_cc_test(
    absl::synchronization
    absl::thread_pool
    absl::base
+    absl::config
    absl::core_headers
    absl::memory
    absl::raw_logging_internal
@@ -179,6 +180,7 @@ absl_cc_library(
  DEPS
    absl::synchronization
    absl::base
+    absl::config
    absl::strings
    absl::time
    gmock
--- a/absl/synchronization/internal/mutex_nonprod.cc
+++ b/absl/synchronization/internal/mutex_nonprod.cc
@@ -27,6 +27,7 @@

 #include <algorithm>

+#include "absl/base/config.h"
 #include "absl/base/internal/raw_logging.h"
 #include "absl/time/time.h"

@@ -278,7 +279,7 @@ bool CondVar::WaitWithTimeout(Mutex* mu, absl::Duration timeout) {

 void CondVar::EnableDebugLog(const char*) {}

-#ifdef THREAD_SANITIZER
+#ifdef ABSL_HAVE_THREAD_SANITIZER
 extern "C" void __tsan_read1(void *addr);
 #else
 #define __tsan_read1(addr)  // do nothing if TSan not enabled
--- a/absl/synchronization/internal/per_thread_sem_test.cc
+++ b/absl/synchronization/internal/per_thread_sem_test.cc
@@ -23,6 +23,7 @@
 #include <thread>              // NOLINT(build/c++11)

 #include "gtest/gtest.h"
+#include "absl/base/config.h"
 #include "absl/base/internal/cycleclock.h"
 #include "absl/base/internal/thread_identity.h"
 #include "absl/strings/str_cat.h"
--- a/absl/synchronization/internal/waiter.h
+++ b/absl/synchronization/internal/waiter.h
@@ -100,7 +100,7 @@ class Waiter {
  }

  // How many periods to remain idle before releasing resources
-#ifndef THREAD_SANITIZER
+#ifndef ABSL_HAVE_THREAD_SANITIZER
  static constexpr int kIdlePeriods = 60;
 #else
  // Memory consumption under ThreadSanitizer is a serious concern,
--- a/absl/synchronization/mutex.cc
+++ b/absl/synchronization/mutex.cc
@@ -77,7 +77,7 @@ ABSL_NAMESPACE_BEGIN

 namespace {

-#if defined(THREAD_SANITIZER)
+#if defined(ABSL_HAVE_THREAD_SANITIZER)
 constexpr OnDeadlockCycle kDeadlockDetectionDefault = OnDeadlockCycle::kIgnore;
 #else
 constexpr OnDeadlockCycle kDeadlockDetectionDefault = OnDeadlockCycle::kAbort;
@@ -705,7 +705,7 @@ static constexpr bool kDebugMode = false;
 static constexpr bool kDebugMode = true;
 #endif

-#ifdef THREAD_SANITIZER
+#ifdef ABSL_HAVE_THREAD_SANITIZER
 static unsigned TsanFlags(Mutex::MuHow how) {
  return how == kShared ? __tsan_mutex_read_lock : 0;
 }
@@ -1767,7 +1767,7 @@ static inline bool EvalConditionAnnotated(const Condition *cond, Mutex *mu,
  // All memory accesses are ignored inside of mutex operations + for unlock
  // operation tsan considers that we've already released the mutex.
  bool res = false;
-#ifdef THREAD_SANITIZER
+#ifdef ABSL_HAVE_THREAD_SANITIZER
  const int flags = read_lock ? __tsan_mutex_read_lock : 0;
  const int tryflags = flags | (trylock ? __tsan_mutex_try_lock : 0);
 #endif
@@ -2683,7 +2683,7 @@ void ReleasableMutexLock::Release() {
  this->mu_ = nullptr;
 }

-#ifdef THREAD_SANITIZER
+#ifdef ABSL_HAVE_THREAD_SANITIZER
 extern "C" void __tsan_read1(void *addr);
 #else
 #define __tsan_read1(addr)  // do nothing if TSan not enabled
--- a/absl/synchronization/mutex_benchmark.cc
+++ b/absl/synchronization/mutex_benchmark.cc
@@ -16,6 +16,7 @@
 #include <mutex>  // NOLINT(build/c++11)
 #include <vector>

+#include "absl/base/config.h"
 #include "absl/base/internal/cycleclock.h"
 #include "absl/base/internal/spinlock.h"
 #include "absl/synchronization/blocking_counter.h"
@@ -213,7 +214,7 @@ void BM_ConditionWaiters(benchmark::State& state) {
 }

 // Some configurations have higher thread limits than others.
-#if defined(__linux__) && !defined(THREAD_SANITIZER)
+#if defined(__linux__) && !defined(ABSL_HAVE_THREAD_SANITIZER)
 constexpr int kMaxConditionWaiters = 8192;
 #else
 constexpr int kMaxConditionWaiters = 1024;
--- a/absl/synchronization/mutex_test.cc
+++ b/absl/synchronization/mutex_test.cc
@@ -30,6 +30,7 @@

 #include "gtest/gtest.h"
 #include "absl/base/attributes.h"
+#include "absl/base/config.h"
 #include "absl/base/internal/raw_logging.h"
 #include "absl/base/internal/sysinfo.h"
 #include "absl/memory/memory.h"
@@ -815,7 +816,7 @@ TEST(Mutex, MutexReaderDecrementBug) ABSL_NO_THREAD_SAFETY_ANALYSIS {

 // Test that we correctly handle the situation when a lock is
 // held and then destroyed (w/o unlocking).
-#ifdef THREAD_SANITIZER
+#ifdef ABSL_HAVE_THREAD_SANITIZER
 // TSAN reports errors when locked Mutexes are destroyed.
 TEST(Mutex, DISABLED_LockedMutexDestructionBug) NO_THREAD_SAFETY_ANALYSIS {
 #else
@@ -1067,7 +1068,7 @@ class ScopedDisableBazelTestWarnings {
 const char ScopedDisableBazelTestWarnings::kVarName[] =
    "TEST_WARNINGS_OUTPUT_FILE";

-#ifdef THREAD_SANITIZER
+#ifdef ABSL_HAVE_THREAD_SANITIZER
 // This test intentionally creates deadlocks to test the deadlock detector.
 TEST(Mutex, DISABLED_DeadlockDetectorBazelWarning) {
 #else
@@ -1119,7 +1120,7 @@ TEST(Mutex, DeadlockDetectorStessTest) ABSL_NO_THREAD_SAFETY_ANALYSIS {
  }
 }

-#ifdef THREAD_SANITIZER
+#ifdef ABSL_HAVE_THREAD_SANITIZER
 // TSAN reports errors when locked Mutexes are destroyed.
 TEST(Mutex, DISABLED_DeadlockIdBug) NO_THREAD_SAFETY_ANALYSIS {
 #else
--- a/absl/time/BUILD.bazel
+++ b/absl/time/BUILD.bazel
@@ -70,6 +70,7 @@ cc_library(
    ],
    deps = [
        ":time",
+        "//absl/base:config",
        "//absl/base:raw_logging_internal",
        "//absl/time/internal/cctz:time_zone",
        "@com_google_googletest//:gtest",
--- a/absl/time/CMakeLists.txt
+++ b/absl/time/CMakeLists.txt
@@ -99,6 +99,7 @@ absl_cc_library(
    ${ABSL_DEFAULT_COPTS}
  DEPS
    absl::time
+    absl::config
    absl::raw_logging_internal
    absl::time_zone
    gmock
--- a/absl/time/internal/test_util.cc
+++ b/absl/time/internal/test_util.cc
@@ -18,6 +18,7 @@
 #include <cstddef>
 #include <cstring>

+#include "absl/base/config.h"
 #include "absl/base/internal/raw_logging.h"
 #include "absl/time/internal/cctz/include/cctz/zone_info_source.h"

--- a/ci/linux_clang-latest_libcxx_asan_bazel.sh
+++ b/ci/linux_clang-latest_libcxx_asan_bazel.sh
@@ -78,8 +78,6 @@ for std in ${STD}; do
        /usr/local/bin/bazel test ... \
          --compilation_mode="${compilation_mode}" \
          --copt="${exceptions_mode}" \
-          --copt="-DADDRESS_SANITIZER" \
-          --copt="-DUNDEFINED_BEHAVIOR_SANITIZER" \
          --copt="-fsanitize=address" \
          --copt="-fsanitize=float-divide-by-zero" \
          --copt="-fsanitize=nullability" \
--- a/ci/linux_clang-latest_libcxx_tsan_bazel.sh
+++ b/ci/linux_clang-latest_libcxx_tsan_bazel.sh
@@ -79,8 +79,6 @@ for std in ${STD}; do
          --build_tag_filters="-notsan" \
          --compilation_mode="${compilation_mode}" \
          --copt="${exceptions_mode}" \
-          --copt="-DDYNAMIC_ANNOTATIONS_ENABLED=1" \
-          --copt="-DTHREAD_SANITIZER" \
          --copt="-fsanitize=thread" \
          --copt="-fno-sanitize-blacklist" \
          --copt=-Werror \