chore(3p/abseil_cpp): unvendor abseil_cpp r/3786

we weren't actually using these sources anymore, okay?

Change-Id: If701571d9716de308d3512e1eb22c35db0877a66
Reviewed-on: https://cl.tvl.fyi/c/depot/+/5248
Tested-by: BuildkiteCI
Reviewed-by: grfn <grfn@gws.fyi>
Autosubmit: tazjin <tazjin@tvl.su>

1 files changed, 0 insertions, 683 deletions

diff --git a/third_party/abseil_cpp/absl/base/attributes.h b/third_party/abseil_cpp/absl/base/attributes.h
deleted file mode 100644
index f1d3cfe4d188..000000000000
--- a/third_party/abseil_cpp/absl/base/attributes.h
+++ /dev/null
@@ -1,683 +0,0 @@
-// Copyright 2017 The Abseil Authors.
-//
-// Licensed under the Apache License, Version 2.0 (the "License");
-// you may not use this file except in compliance with the License.
-// You may obtain a copy of the License at
-//
-//      https://www.apache.org/licenses/LICENSE-2.0
-//
-// Unless required by applicable law or agreed to in writing, software
-// distributed under the License is distributed on an "AS IS" BASIS,
-// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-// See the License for the specific language governing permissions and
-// limitations under the License.
-//
-// This header file defines macros for declaring attributes for functions,
-// types, and variables.
-//
-// These macros are used within Abseil and allow the compiler to optimize, where
-// applicable, certain function calls.
-//
-// This file is used for both C and C++!
-//
-// Most macros here are exposing GCC or Clang features, and are stubbed out for
-// other compilers.
-//
-// GCC attributes documentation:
-//   https://gcc.gnu.org/onlinedocs/gcc-4.7.0/gcc/Function-Attributes.html
-//   https://gcc.gnu.org/onlinedocs/gcc-4.7.0/gcc/Variable-Attributes.html
-//   https://gcc.gnu.org/onlinedocs/gcc-4.7.0/gcc/Type-Attributes.html
-//
-// Most attributes in this file are already supported by GCC 4.7. However, some
-// 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).
-
-#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
-// `__has_attribute`, which is defined by GCC 5+ and Clang and evaluates to a
-// nonzero constant integer if the attribute is supported or 0 if not.
-//
-// It evaluates to zero if `__has_attribute` is not defined by the compiler.
-//
-// GCC: https://gcc.gnu.org/gcc-5/changes.html
-// Clang: https://clang.llvm.org/docs/LanguageExtensions.html
-#ifdef __has_attribute
-#define ABSL_HAVE_ATTRIBUTE(x) __has_attribute(x)
-#else
-#define ABSL_HAVE_ATTRIBUTE(x) 0
-#endif
-
-// ABSL_HAVE_CPP_ATTRIBUTE
-//
-// A function-like feature checking macro that accepts C++11 style attributes.
-// It's a wrapper around `__has_cpp_attribute`, defined by ISO C++ SD-6
-// (https://en.cppreference.com/w/cpp/experimental/feature_test). If we don't
-// find `__has_cpp_attribute`, will evaluate to 0.
-#if defined(__cplusplus) && defined(__has_cpp_attribute)
-// NOTE: requiring __cplusplus above should not be necessary, but
-// works around https://bugs.llvm.org/show_bug.cgi?id=23435.
-#define ABSL_HAVE_CPP_ATTRIBUTE(x) __has_cpp_attribute(x)
-#else
-#define ABSL_HAVE_CPP_ATTRIBUTE(x) 0
-#endif
-
-// -----------------------------------------------------------------------------
-// Function Attributes
-// -----------------------------------------------------------------------------
-//
-// GCC: https://gcc.gnu.org/onlinedocs/gcc/Function-Attributes.html
-// Clang: https://clang.llvm.org/docs/AttributeReference.html
-
-// ABSL_PRINTF_ATTRIBUTE
-// ABSL_SCANF_ATTRIBUTE
-//
-// Tells the compiler to perform `printf` format string checking if the
-// compiler supports it; see the 'format' attribute in
-// <https://gcc.gnu.org/onlinedocs/gcc-4.7.0/gcc/Function-Attributes.html>.
-//
-// Note: As the GCC manual states, "[s]ince non-static C++ methods
-// have an implicit 'this' argument, the arguments of such methods
-// should be counted from two, not one."
-#if ABSL_HAVE_ATTRIBUTE(format) || (defined(__GNUC__) && !defined(__clang__))
-#define ABSL_PRINTF_ATTRIBUTE(string_index, first_to_check) \
-  __attribute__((__format__(__printf__, string_index, first_to_check)))
-#define ABSL_SCANF_ATTRIBUTE(string_index, first_to_check) \
-  __attribute__((__format__(__scanf__, string_index, first_to_check)))
-#else
-#define ABSL_PRINTF_ATTRIBUTE(string_index, first_to_check)
-#define ABSL_SCANF_ATTRIBUTE(string_index, first_to_check)
-#endif
-
-// ABSL_ATTRIBUTE_ALWAYS_INLINE
-// ABSL_ATTRIBUTE_NOINLINE
-//
-// Forces functions to either inline or not inline. Introduced in gcc 3.1.
-#if ABSL_HAVE_ATTRIBUTE(always_inline) || \
-    (defined(__GNUC__) && !defined(__clang__))
-#define ABSL_ATTRIBUTE_ALWAYS_INLINE __attribute__((always_inline))
-#define ABSL_HAVE_ATTRIBUTE_ALWAYS_INLINE 1
-#else
-#define ABSL_ATTRIBUTE_ALWAYS_INLINE
-#endif
-
-#if ABSL_HAVE_ATTRIBUTE(noinline) || (defined(__GNUC__) && !defined(__clang__))
-#define ABSL_ATTRIBUTE_NOINLINE __attribute__((noinline))
-#define ABSL_HAVE_ATTRIBUTE_NOINLINE 1
-#else
-#define ABSL_ATTRIBUTE_NOINLINE
-#endif
-
-// ABSL_ATTRIBUTE_NO_TAIL_CALL
-//
-// Prevents the compiler from optimizing away stack frames for functions which
-// end in a call to another function.
-#if ABSL_HAVE_ATTRIBUTE(disable_tail_calls)
-#define ABSL_HAVE_ATTRIBUTE_NO_TAIL_CALL 1
-#define ABSL_ATTRIBUTE_NO_TAIL_CALL __attribute__((disable_tail_calls))
-#elif defined(__GNUC__) && !defined(__clang__)
-#define ABSL_HAVE_ATTRIBUTE_NO_TAIL_CALL 1
-#define ABSL_ATTRIBUTE_NO_TAIL_CALL \
-  __attribute__((optimize("no-optimize-sibling-calls")))
-#else
-#define ABSL_ATTRIBUTE_NO_TAIL_CALL
-#define ABSL_HAVE_ATTRIBUTE_NO_TAIL_CALL 0
-#endif
-
-// ABSL_ATTRIBUTE_WEAK
-//
-// Tags a function as weak for the purposes of compilation and linking.
-// Weak attributes currently do not work properly in LLVM's Windows backend,
-// so disable them there. See https://bugs.llvm.org/show_bug.cgi?id=37598
-// for further information.
-// The MinGW compiler doesn't complain about the weak attribute until the link
-// step, presumably because Windows doesn't use ELF binaries.
-#if (ABSL_HAVE_ATTRIBUTE(weak) ||                   \
-     (defined(__GNUC__) && !defined(__clang__))) && \
-    !(defined(__llvm__) && defined(_WIN32)) && !defined(__MINGW32__)
-#undef ABSL_ATTRIBUTE_WEAK
-#define ABSL_ATTRIBUTE_WEAK __attribute__((weak))
-#define ABSL_HAVE_ATTRIBUTE_WEAK 1
-#else
-#define ABSL_ATTRIBUTE_WEAK
-#define ABSL_HAVE_ATTRIBUTE_WEAK 0
-#endif
-
-// ABSL_ATTRIBUTE_NONNULL
-//
-// Tells the compiler either (a) that a particular function parameter
-// should be a non-null pointer, or (b) that all pointer arguments should
-// be non-null.
-//
-// Note: As the GCC manual states, "[s]ince non-static C++ methods
-// have an implicit 'this' argument, the arguments of such methods
-// should be counted from two, not one."
-//
-// Args are indexed starting at 1.
-//
-// For non-static class member functions, the implicit `this` argument
-// is arg 1, and the first explicit argument is arg 2. For static class member
-// functions, there is no implicit `this`, and the first explicit argument is
-// arg 1.
-//
-// Example:
-//
-//   /* arg_a cannot be null, but arg_b can */
-//   void Function(void* arg_a, void* arg_b) ABSL_ATTRIBUTE_NONNULL(1);
-//
-//   class C {
-//     /* arg_a cannot be null, but arg_b can */
-//     void Method(void* arg_a, void* arg_b) ABSL_ATTRIBUTE_NONNULL(2);
-//
-//     /* arg_a cannot be null, but arg_b can */
-//     static void StaticMethod(void* arg_a, void* arg_b)
-//     ABSL_ATTRIBUTE_NONNULL(1);
-//   };
-//
-// If no arguments are provided, then all pointer arguments should be non-null.
-//
-//  /* No pointer arguments may be null. */
-//  void Function(void* arg_a, void* arg_b, int arg_c) ABSL_ATTRIBUTE_NONNULL();
-//
-// NOTE: The GCC nonnull attribute actually accepts a list of arguments, but
-// ABSL_ATTRIBUTE_NONNULL does not.
-#if ABSL_HAVE_ATTRIBUTE(nonnull) || (defined(__GNUC__) && !defined(__clang__))
-#define ABSL_ATTRIBUTE_NONNULL(arg_index) __attribute__((nonnull(arg_index)))
-#else
-#define ABSL_ATTRIBUTE_NONNULL(...)
-#endif
-
-// ABSL_ATTRIBUTE_NORETURN
-//
-// Tells the compiler that a given function never returns.
-#if ABSL_HAVE_ATTRIBUTE(noreturn) || (defined(__GNUC__) && !defined(__clang__))
-#define ABSL_ATTRIBUTE_NORETURN __attribute__((noreturn))
-#elif defined(_MSC_VER)
-#define ABSL_ATTRIBUTE_NORETURN __declspec(noreturn)
-#else
-#define ABSL_ATTRIBUTE_NORETURN
-#endif
-
-// ABSL_ATTRIBUTE_NO_SANITIZE_ADDRESS
-//
-// Tells the AddressSanitizer (or other memory testing tools) to ignore a given
-// function. Useful for cases when a function reads random locations on stack,
-// calls _exit from a cloned subprocess, deliberately accesses buffer
-// 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 ABSL_HAVE_ATTRIBUTE(no_sanitize_address)
-#define ABSL_ATTRIBUTE_NO_SANITIZE_ADDRESS __attribute__((no_sanitize_address))
-#else
-#define ABSL_ATTRIBUTE_NO_SANITIZE_ADDRESS
-#endif
-
-// 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 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 ABSL_HAVE_ATTRIBUTE(no_sanitize_memory)
-#define ABSL_ATTRIBUTE_NO_SANITIZE_MEMORY __attribute__((no_sanitize_memory))
-#else
-#define ABSL_ATTRIBUTE_NO_SANITIZE_MEMORY
-#endif
-
-// ABSL_ATTRIBUTE_NO_SANITIZE_THREAD
-//
-// 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 ABSL_HAVE_ATTRIBUTE(no_sanitize_thread)
-#define ABSL_ATTRIBUTE_NO_SANITIZE_THREAD __attribute__((no_sanitize_thread))
-#else
-#define ABSL_ATTRIBUTE_NO_SANITIZE_THREAD
-#endif
-
-// ABSL_ATTRIBUTE_NO_SANITIZE_UNDEFINED
-//
-// Tells the UndefinedSanitizer to ignore a given function. Useful for cases
-// 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 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
-#define ABSL_ATTRIBUTE_NO_SANITIZE_UNDEFINED
-#endif
-
-// ABSL_ATTRIBUTE_NO_SANITIZE_CFI
-//
-// Tells the ControlFlowIntegrity sanitizer to not instrument a given function.
-// See https://clang.llvm.org/docs/ControlFlowIntegrity.html for details.
-#if ABSL_HAVE_ATTRIBUTE(no_sanitize)
-#define ABSL_ATTRIBUTE_NO_SANITIZE_CFI __attribute__((no_sanitize("cfi")))
-#else
-#define ABSL_ATTRIBUTE_NO_SANITIZE_CFI
-#endif
-
-// ABSL_ATTRIBUTE_NO_SANITIZE_SAFESTACK
-//
-// Tells the SafeStack to not instrument a given function.
-// See https://clang.llvm.org/docs/SafeStack.html for details.
-#if ABSL_HAVE_ATTRIBUTE(no_sanitize)
-#define ABSL_ATTRIBUTE_NO_SANITIZE_SAFESTACK \
-  __attribute__((no_sanitize("safe-stack")))
-#else
-#define ABSL_ATTRIBUTE_NO_SANITIZE_SAFESTACK
-#endif
-
-// ABSL_ATTRIBUTE_RETURNS_NONNULL
-//
-// Tells the compiler that a particular function never returns a null pointer.
-#if ABSL_HAVE_ATTRIBUTE(returns_nonnull) || \
-    (defined(__GNUC__) && \
-     (__GNUC__ > 5 || (__GNUC__ == 4 && __GNUC_MINOR__ >= 9)) && \
-     !defined(__clang__))
-#define ABSL_ATTRIBUTE_RETURNS_NONNULL __attribute__((returns_nonnull))
-#else
-#define ABSL_ATTRIBUTE_RETURNS_NONNULL
-#endif
-
-// ABSL_HAVE_ATTRIBUTE_SECTION
-//
-// Indicates whether labeled sections are supported. Weak symbol support is
-// a prerequisite. Labeled sections are not supported on Darwin/iOS.
-#ifdef ABSL_HAVE_ATTRIBUTE_SECTION
-#error ABSL_HAVE_ATTRIBUTE_SECTION cannot be directly set
-#elif (ABSL_HAVE_ATTRIBUTE(section) ||                \
-       (defined(__GNUC__) && !defined(__clang__))) && \
-    !defined(__APPLE__) && ABSL_HAVE_ATTRIBUTE_WEAK
-#define ABSL_HAVE_ATTRIBUTE_SECTION 1
-
-// ABSL_ATTRIBUTE_SECTION
-//
-// Tells the compiler/linker to put a given function into a section and define
-// `__start_ ## name` and `__stop_ ## name` symbols to bracket the section.
-// This functionality is supported by GNU linker.  Any function annotated with
-// `ABSL_ATTRIBUTE_SECTION` must not be inlined, or it will be placed into
-// whatever section its caller is placed into.
-//
-#ifndef ABSL_ATTRIBUTE_SECTION
-#define ABSL_ATTRIBUTE_SECTION(name) \
-  __attribute__((section(#name))) __attribute__((noinline))
-#endif
-
-
-// ABSL_ATTRIBUTE_SECTION_VARIABLE
-//
-// Tells the compiler/linker to put a given variable into a section and define
-// `__start_ ## name` and `__stop_ ## name` symbols to bracket the section.
-// This functionality is supported by GNU linker.
-#ifndef ABSL_ATTRIBUTE_SECTION_VARIABLE
-#define ABSL_ATTRIBUTE_SECTION_VARIABLE(name) __attribute__((section(#name)))
-#endif
-
-// ABSL_DECLARE_ATTRIBUTE_SECTION_VARS
-//
-// A weak section declaration to be used as a global declaration
-// for ABSL_ATTRIBUTE_SECTION_START|STOP(name) to compile and link
-// even without functions with ABSL_ATTRIBUTE_SECTION(name).
-// ABSL_DEFINE_ATTRIBUTE_SECTION should be in the exactly one file; it's
-// a no-op on ELF but not on Mach-O.
-//
-#ifndef ABSL_DECLARE_ATTRIBUTE_SECTION_VARS
-#define ABSL_DECLARE_ATTRIBUTE_SECTION_VARS(name) \
-  extern char __start_##name[] ABSL_ATTRIBUTE_WEAK;    \
-  extern char __stop_##name[] ABSL_ATTRIBUTE_WEAK
-#endif
-#ifndef ABSL_DEFINE_ATTRIBUTE_SECTION_VARS
-#define ABSL_INIT_ATTRIBUTE_SECTION_VARS(name)
-#define ABSL_DEFINE_ATTRIBUTE_SECTION_VARS(name)
-#endif
-
-// ABSL_ATTRIBUTE_SECTION_START
-//
-// Returns `void*` pointers to start/end of a section of code with
-// functions having ABSL_ATTRIBUTE_SECTION(name).
-// Returns 0 if no such functions exist.
-// One must ABSL_DECLARE_ATTRIBUTE_SECTION_VARS(name) for this to compile and
-// link.
-//
-#define ABSL_ATTRIBUTE_SECTION_START(name) \
-  (reinterpret_cast<void *>(__start_##name))
-#define ABSL_ATTRIBUTE_SECTION_STOP(name) \
-  (reinterpret_cast<void *>(__stop_##name))
-
-#else  // !ABSL_HAVE_ATTRIBUTE_SECTION
-
-#define ABSL_HAVE_ATTRIBUTE_SECTION 0
-
-// provide dummy definitions
-#define ABSL_ATTRIBUTE_SECTION(name)
-#define ABSL_ATTRIBUTE_SECTION_VARIABLE(name)
-#define ABSL_INIT_ATTRIBUTE_SECTION_VARS(name)
-#define ABSL_DEFINE_ATTRIBUTE_SECTION_VARS(name)
-#define ABSL_DECLARE_ATTRIBUTE_SECTION_VARS(name)
-#define ABSL_ATTRIBUTE_SECTION_START(name) (reinterpret_cast<void *>(0))
-#define ABSL_ATTRIBUTE_SECTION_STOP(name) (reinterpret_cast<void *>(0))
-
-#endif  // ABSL_ATTRIBUTE_SECTION
-
-// ABSL_ATTRIBUTE_STACK_ALIGN_FOR_OLD_LIBC
-//
-// Support for aligning the stack on 32-bit x86.
-#if ABSL_HAVE_ATTRIBUTE(force_align_arg_pointer) || \
-    (defined(__GNUC__) && !defined(__clang__))
-#if defined(__i386__)
-#define ABSL_ATTRIBUTE_STACK_ALIGN_FOR_OLD_LIBC \
-  __attribute__((force_align_arg_pointer))
-#define ABSL_REQUIRE_STACK_ALIGN_TRAMPOLINE (0)
-#elif defined(__x86_64__)
-#define ABSL_REQUIRE_STACK_ALIGN_TRAMPOLINE (1)
-#define ABSL_ATTRIBUTE_STACK_ALIGN_FOR_OLD_LIBC
-#else  // !__i386__ && !__x86_64
-#define ABSL_REQUIRE_STACK_ALIGN_TRAMPOLINE (0)
-#define ABSL_ATTRIBUTE_STACK_ALIGN_FOR_OLD_LIBC
-#endif  // __i386__
-#else
-#define ABSL_ATTRIBUTE_STACK_ALIGN_FOR_OLD_LIBC
-#define ABSL_REQUIRE_STACK_ALIGN_TRAMPOLINE (0)
-#endif
-
-// ABSL_MUST_USE_RESULT
-//
-// Tells the compiler to warn about unused results.
-//
-// When annotating a function, it must appear as the first part of the
-// declaration or definition. The compiler will warn if the return value from
-// such a function is unused:
-//
-//   ABSL_MUST_USE_RESULT Sprocket* AllocateSprocket();
-//   AllocateSprocket();  // Triggers a warning.
-//
-// When annotating a class, it is equivalent to annotating every function which
-// returns an instance.
-//
-//   class ABSL_MUST_USE_RESULT Sprocket {};
-//   Sprocket();  // Triggers a warning.
-//
-//   Sprocket MakeSprocket();
-//   MakeSprocket();  // Triggers a warning.
-//
-// Note that references and pointers are not instances:
-//
-//   Sprocket* SprocketPointer();
-//   SprocketPointer();  // Does *not* trigger a warning.
-//
-// ABSL_MUST_USE_RESULT allows using cast-to-void to suppress the unused result
-// warning. For that, warn_unused_result is used only for clang but not for gcc.
-// https://gcc.gnu.org/bugzilla/show_bug.cgi?id=66425
-//
-// Note: past advice was to place the macro after the argument list.
-#if ABSL_HAVE_ATTRIBUTE(nodiscard)
-#define ABSL_MUST_USE_RESULT [[nodiscard]]
-#elif defined(__clang__) && ABSL_HAVE_ATTRIBUTE(warn_unused_result)
-#define ABSL_MUST_USE_RESULT __attribute__((warn_unused_result))
-#else
-#define ABSL_MUST_USE_RESULT
-#endif
-
-// ABSL_ATTRIBUTE_HOT, ABSL_ATTRIBUTE_COLD
-//
-// Tells GCC that a function is hot or cold. GCC can use this information to
-// improve static analysis, i.e. a conditional branch to a cold function
-// is likely to be not-taken.
-// This annotation is used for function declarations.
-//
-// Example:
-//
-//   int foo() ABSL_ATTRIBUTE_HOT;
-#if ABSL_HAVE_ATTRIBUTE(hot) || (defined(__GNUC__) && !defined(__clang__))
-#define ABSL_ATTRIBUTE_HOT __attribute__((hot))
-#else
-#define ABSL_ATTRIBUTE_HOT
-#endif
-
-#if ABSL_HAVE_ATTRIBUTE(cold) || (defined(__GNUC__) && !defined(__clang__))
-#define ABSL_ATTRIBUTE_COLD __attribute__((cold))
-#else
-#define ABSL_ATTRIBUTE_COLD
-#endif
-
-// ABSL_XRAY_ALWAYS_INSTRUMENT, ABSL_XRAY_NEVER_INSTRUMENT, ABSL_XRAY_LOG_ARGS
-//
-// We define the ABSL_XRAY_ALWAYS_INSTRUMENT and ABSL_XRAY_NEVER_INSTRUMENT
-// macro used as an attribute to mark functions that must always or never be
-// instrumented by XRay. Currently, this is only supported in Clang/LLVM.
-//
-// For reference on the LLVM XRay instrumentation, see
-// http://llvm.org/docs/XRay.html.
-//
-// A function with the XRAY_ALWAYS_INSTRUMENT macro attribute in its declaration
-// will always get the XRay instrumentation sleds. These sleds may introduce
-// some binary size and runtime overhead and must be used sparingly.
-//
-// These attributes only take effect when the following conditions are met:
-//
-//   * The file/target is built in at least C++11 mode, with a Clang compiler
-//     that supports XRay attributes.
-//   * The file/target is built with the -fxray-instrument flag set for the
-//     Clang/LLVM compiler.
-//   * The function is defined in the translation unit (the compiler honors the
-//     attribute in either the definition or the declaration, and must match).
-//
-// There are cases when, even when building with XRay instrumentation, users
-// might want to control specifically which functions are instrumented for a
-// particular build using special-case lists provided to the compiler. These
-// special case lists are provided to Clang via the
-// -fxray-always-instrument=... and -fxray-never-instrument=... flags. The
-// attributes in source take precedence over these special-case lists.
-//
-// To disable the XRay attributes at build-time, users may define
-// ABSL_NO_XRAY_ATTRIBUTES. Do NOT define ABSL_NO_XRAY_ATTRIBUTES on specific
-// packages/targets, as this may lead to conflicting definitions of functions at
-// link-time.
-//
-// XRay isn't currently supported on Android:
-// https://github.com/android/ndk/issues/368
-#if ABSL_HAVE_CPP_ATTRIBUTE(clang::xray_always_instrument) && \
-    !defined(ABSL_NO_XRAY_ATTRIBUTES) && !defined(__ANDROID__)
-#define ABSL_XRAY_ALWAYS_INSTRUMENT [[clang::xray_always_instrument]]
-#define ABSL_XRAY_NEVER_INSTRUMENT [[clang::xray_never_instrument]]
-#if ABSL_HAVE_CPP_ATTRIBUTE(clang::xray_log_args)
-#define ABSL_XRAY_LOG_ARGS(N) \
-    [[clang::xray_always_instrument, clang::xray_log_args(N)]]
-#else
-#define ABSL_XRAY_LOG_ARGS(N) [[clang::xray_always_instrument]]
-#endif
-#else
-#define ABSL_XRAY_ALWAYS_INSTRUMENT
-#define ABSL_XRAY_NEVER_INSTRUMENT
-#define ABSL_XRAY_LOG_ARGS(N)
-#endif
-
-// ABSL_ATTRIBUTE_REINITIALIZES
-//
-// Indicates that a member function reinitializes the entire object to a known
-// state, independent of the previous state of the object.
-//
-// The clang-tidy check bugprone-use-after-move allows member functions marked
-// with this attribute to be called on objects that have been moved from;
-// without the attribute, this would result in a use-after-move warning.
-#if ABSL_HAVE_CPP_ATTRIBUTE(clang::reinitializes)
-#define ABSL_ATTRIBUTE_REINITIALIZES [[clang::reinitializes]]
-#else
-#define ABSL_ATTRIBUTE_REINITIALIZES
-#endif
-
-// -----------------------------------------------------------------------------
-// Variable Attributes
-// -----------------------------------------------------------------------------
-
-// ABSL_ATTRIBUTE_UNUSED
-//
-// Prevents the compiler from complaining about variables that appear unused.
-#if ABSL_HAVE_ATTRIBUTE(unused) || (defined(__GNUC__) && !defined(__clang__))
-#undef ABSL_ATTRIBUTE_UNUSED
-#define ABSL_ATTRIBUTE_UNUSED __attribute__((__unused__))
-#else
-#define ABSL_ATTRIBUTE_UNUSED
-#endif
-
-// ABSL_ATTRIBUTE_INITIAL_EXEC
-//
-// Tells the compiler to use "initial-exec" mode for a thread-local variable.
-// See http://people.redhat.com/drepper/tls.pdf for the gory details.
-#if ABSL_HAVE_ATTRIBUTE(tls_model) || (defined(__GNUC__) && !defined(__clang__))
-#define ABSL_ATTRIBUTE_INITIAL_EXEC __attribute__((tls_model("initial-exec")))
-#else
-#define ABSL_ATTRIBUTE_INITIAL_EXEC
-#endif
-
-// ABSL_ATTRIBUTE_PACKED
-//
-// Instructs the compiler not to use natural alignment for a tagged data
-// structure, but instead to reduce its alignment to 1. This attribute can
-// either be applied to members of a structure or to a structure in its
-// entirety. Applying this attribute (judiciously) to a structure in its
-// entirety to optimize the memory footprint of very commonly-used structs is
-// fine. Do not apply this attribute to a structure in its entirety if the
-// purpose is to control the offsets of the members in the structure. Instead,
-// apply this attribute only to structure members that need it.
-//
-// When applying ABSL_ATTRIBUTE_PACKED only to specific structure members the
-// natural alignment of structure members not annotated is preserved. Aligned
-// member accesses are faster than non-aligned member accesses even if the
-// targeted microprocessor supports non-aligned accesses.
-#if ABSL_HAVE_ATTRIBUTE(packed) || (defined(__GNUC__) && !defined(__clang__))
-#define ABSL_ATTRIBUTE_PACKED __attribute__((__packed__))
-#else
-#define ABSL_ATTRIBUTE_PACKED
-#endif
-
-// ABSL_ATTRIBUTE_FUNC_ALIGN
-//
-// Tells the compiler to align the function start at least to certain
-// alignment boundary
-#if ABSL_HAVE_ATTRIBUTE(aligned) || (defined(__GNUC__) && !defined(__clang__))
-#define ABSL_ATTRIBUTE_FUNC_ALIGN(bytes) __attribute__((aligned(bytes)))
-#else
-#define ABSL_ATTRIBUTE_FUNC_ALIGN(bytes)
-#endif
-
-// ABSL_FALLTHROUGH_INTENDED
-//
-// Annotates implicit fall-through between switch labels, allowing a case to
-// indicate intentional fallthrough and turn off warnings about any lack of a
-// `break` statement. The ABSL_FALLTHROUGH_INTENDED macro should be followed by
-// a semicolon and can be used in most places where `break` can, provided that
-// no statements exist between it and the next switch label.
-//
-// Example:
-//
-//  switch (x) {
-//    case 40:
-//    case 41:
-//      if (truth_is_out_there) {
-//        ++x;
-//        ABSL_FALLTHROUGH_INTENDED;  // Use instead of/along with annotations
-//                                    // in comments
-//      } else {
-//        return x;
-//      }
-//    case 42:
-//      ...
-//
-// Notes: when compiled with clang in C++11 mode, the ABSL_FALLTHROUGH_INTENDED
-// macro is expanded to the [[clang::fallthrough]] attribute, which is analysed
-// when  performing switch labels fall-through diagnostic
-// (`-Wimplicit-fallthrough`). See clang documentation on language extensions
-// for details:
-// https://clang.llvm.org/docs/AttributeReference.html#fallthrough-clang-fallthrough
-//
-// When used with unsupported compilers, the ABSL_FALLTHROUGH_INTENDED macro
-// has no effect on diagnostics. In any case this macro has no effect on runtime
-// behavior and performance of code.
-
-#ifdef ABSL_FALLTHROUGH_INTENDED
-#error "ABSL_FALLTHROUGH_INTENDED should not be defined."
-#endif
-
-// TODO(zhangxy): Use c++17 standard [[fallthrough]] macro, when supported.
-#if defined(__clang__) && defined(__has_warning)
-#if __has_feature(cxx_attributes) && __has_warning("-Wimplicit-fallthrough")
-#define ABSL_FALLTHROUGH_INTENDED [[clang::fallthrough]]
-#endif
-#elif defined(__GNUC__) && __GNUC__ >= 7
-#define ABSL_FALLTHROUGH_INTENDED [[gnu::fallthrough]]
-#endif
-
-#ifndef ABSL_FALLTHROUGH_INTENDED
-#define ABSL_FALLTHROUGH_INTENDED \
-  do {                            \
-  } while (0)
-#endif
-
-// ABSL_DEPRECATED()
-//
-// Marks a deprecated class, struct, enum, function, method and variable
-// declarations. The macro argument is used as a custom diagnostic message (e.g.
-// suggestion of a better alternative).
-//
-// Examples:
-//
-//   class ABSL_DEPRECATED("Use Bar instead") Foo {...};
-//
-//   ABSL_DEPRECATED("Use Baz() instead") void Bar() {...}
-//
-//   template <typename T>
-//   ABSL_DEPRECATED("Use DoThat() instead")
-//   void DoThis();
-//
-// Every usage of a deprecated entity will trigger a warning when compiled with
-// clang's `-Wdeprecated-declarations` option. This option is turned off by
-// default, but the warnings will be reported by clang-tidy.
-#if defined(__clang__) && __cplusplus >= 201103L
-#define ABSL_DEPRECATED(message) __attribute__((deprecated(message)))
-#endif
-
-#ifndef ABSL_DEPRECATED
-#define ABSL_DEPRECATED(message)
-#endif
-
-// ABSL_CONST_INIT
-//
-// A variable declaration annotated with the `ABSL_CONST_INIT` attribute will
-// not compile (on supported platforms) unless the variable has a constant
-// initializer. This is useful for variables with static and thread storage
-// duration, because it guarantees that they will not suffer from the so-called
-// "static init order fiasco".  Prefer to put this attribute on the most visible
-// declaration of the variable, if there's more than one, because code that
-// accesses the variable can then use the attribute for optimization.
-//
-// Example:
-//
-//   class MyClass {
-//    public:
-//     ABSL_CONST_INIT static MyType my_var;
-//   };
-//
-//   MyType MyClass::my_var = MakeMyType(...);
-//
-// Note that this attribute is redundant if the variable is declared constexpr.
-#if ABSL_HAVE_CPP_ATTRIBUTE(clang::require_constant_initialization)
-#define ABSL_CONST_INIT [[clang::require_constant_initialization]]
-#else
-#define ABSL_CONST_INIT
-#endif  // ABSL_HAVE_CPP_ATTRIBUTE(clang::require_constant_initialization)
-
-#endif  // ABSL_BASE_ATTRIBUTES_H_