git-subtree-dir: third_party/abseil_cpp git-subtree-mainline:ffb2ae54begit-subtree-split:768eb2ca28
		
			
				
	
	
		
			664 lines
		
	
	
	
		
			24 KiB
		
	
	
	
		
			C++
		
	
	
	
	
	
			
		
		
	
	
			664 lines
		
	
	
	
		
			24 KiB
		
	
	
	
		
			C++
		
	
	
	
	
	
| //
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| // Copyright 2017 The Abseil Authors.
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| //
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| // Licensed under the Apache License, Version 2.0 (the "License");
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| // you may not use this file except in compliance with the License.
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| // You may obtain a copy of the License at
 | |
| //
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| //      https://www.apache.org/licenses/LICENSE-2.0
 | |
| //
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| // 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.
 | |
| //
 | |
| // -----------------------------------------------------------------------------
 | |
| // File: config.h
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| // -----------------------------------------------------------------------------
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| //
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| // This header file defines a set of macros for checking the presence of
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| // important compiler and platform features. Such macros can be used to
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| // produce portable code by parameterizing compilation based on the presence or
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| // lack of a given feature.
 | |
| //
 | |
| // We define a "feature" as some interface we wish to program to: for example,
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| // a library function or system call. A value of `1` indicates support for
 | |
| // that feature; any other value indicates the feature support is undefined.
 | |
| //
 | |
| // Example:
 | |
| //
 | |
| // Suppose a programmer wants to write a program that uses the 'mmap()' system
 | |
| // call. The Abseil macro for that feature (`ABSL_HAVE_MMAP`) allows you to
 | |
| // selectively include the `mmap.h` header and bracket code using that feature
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| // in the macro:
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| //
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| //   #include "absl/base/config.h"
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| //
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| //   #ifdef ABSL_HAVE_MMAP
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| //   #include "sys/mman.h"
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| //   #endif  //ABSL_HAVE_MMAP
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| //
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| //   ...
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| //   #ifdef ABSL_HAVE_MMAP
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| //   void *ptr = mmap(...);
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| //   ...
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| //   #endif  // ABSL_HAVE_MMAP
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| 
 | |
| #ifndef ABSL_BASE_CONFIG_H_
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| #define ABSL_BASE_CONFIG_H_
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| 
 | |
| // Included for the __GLIBC__ macro (or similar macros on other systems).
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| #include <limits.h>
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| 
 | |
| #ifdef __cplusplus
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| // Included for __GLIBCXX__, _LIBCPP_VERSION
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| #include <cstddef>
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| #endif  // __cplusplus
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| 
 | |
| #if defined(__APPLE__)
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| // Included for TARGET_OS_IPHONE, __IPHONE_OS_VERSION_MIN_REQUIRED,
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| // __IPHONE_8_0.
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| #include <Availability.h>
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| #include <TargetConditionals.h>
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| #endif
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| 
 | |
| #include "absl/base/options.h"
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| #include "absl/base/policy_checks.h"
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| 
 | |
| // Helper macro to convert a CPP variable to a string literal.
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| #define ABSL_INTERNAL_DO_TOKEN_STR(x) #x
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| #define ABSL_INTERNAL_TOKEN_STR(x) ABSL_INTERNAL_DO_TOKEN_STR(x)
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| 
 | |
| // -----------------------------------------------------------------------------
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| // Abseil namespace annotations
 | |
| // -----------------------------------------------------------------------------
 | |
| 
 | |
| // ABSL_NAMESPACE_BEGIN/ABSL_NAMESPACE_END
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| //
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| // An annotation placed at the beginning/end of each `namespace absl` scope.
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| // This is used to inject an inline namespace.
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| //
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| // The proper way to write Abseil code in the `absl` namespace is:
 | |
| //
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| // namespace absl {
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| // ABSL_NAMESPACE_BEGIN
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| //
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| // void Foo();  // absl::Foo().
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| //
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| // ABSL_NAMESPACE_END
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| // }  // namespace absl
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| //
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| // Users of Abseil should not use these macros, because users of Abseil should
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| // not write `namespace absl {` in their own code for any reason.  (Abseil does
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| // not support forward declarations of its own types, nor does it support
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| // user-provided specialization of Abseil templates.  Code that violates these
 | |
| // rules may be broken without warning.)
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| #if !defined(ABSL_OPTION_USE_INLINE_NAMESPACE) || \
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|     !defined(ABSL_OPTION_INLINE_NAMESPACE_NAME)
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| #error options.h is misconfigured.
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| #endif
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| 
 | |
| // Check that ABSL_OPTION_INLINE_NAMESPACE_NAME is neither "head" nor ""
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| #if defined(__cplusplus) && ABSL_OPTION_USE_INLINE_NAMESPACE == 1
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| 
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| #define ABSL_INTERNAL_INLINE_NAMESPACE_STR \
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|   ABSL_INTERNAL_TOKEN_STR(ABSL_OPTION_INLINE_NAMESPACE_NAME)
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| 
 | |
| static_assert(ABSL_INTERNAL_INLINE_NAMESPACE_STR[0] != '\0',
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|               "options.h misconfigured: ABSL_OPTION_INLINE_NAMESPACE_NAME must "
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|               "not be empty.");
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| static_assert(ABSL_INTERNAL_INLINE_NAMESPACE_STR[0] != 'h' ||
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|                   ABSL_INTERNAL_INLINE_NAMESPACE_STR[1] != 'e' ||
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|                   ABSL_INTERNAL_INLINE_NAMESPACE_STR[2] != 'a' ||
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|                   ABSL_INTERNAL_INLINE_NAMESPACE_STR[3] != 'd' ||
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|                   ABSL_INTERNAL_INLINE_NAMESPACE_STR[4] != '\0',
 | |
|               "options.h misconfigured: ABSL_OPTION_INLINE_NAMESPACE_NAME must "
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|               "be changed to a new, unique identifier name.");
 | |
| 
 | |
| #endif
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| 
 | |
| #if ABSL_OPTION_USE_INLINE_NAMESPACE == 0
 | |
| #define ABSL_NAMESPACE_BEGIN
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| #define ABSL_NAMESPACE_END
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| #elif ABSL_OPTION_USE_INLINE_NAMESPACE == 1
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| #define ABSL_NAMESPACE_BEGIN \
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|   inline namespace ABSL_OPTION_INLINE_NAMESPACE_NAME {
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| #define ABSL_NAMESPACE_END }
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| #else
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| #error options.h is misconfigured.
 | |
| #endif
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| 
 | |
| // -----------------------------------------------------------------------------
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| // Compiler Feature Checks
 | |
| // -----------------------------------------------------------------------------
 | |
| 
 | |
| // ABSL_HAVE_BUILTIN()
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| //
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| // Checks whether the compiler supports a Clang Feature Checking Macro, and if
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| // so, checks whether it supports the provided builtin function "x" where x
 | |
| // is one of the functions noted in
 | |
| // https://clang.llvm.org/docs/LanguageExtensions.html
 | |
| //
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| // Note: Use this macro to avoid an extra level of #ifdef __has_builtin check.
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| // http://releases.llvm.org/3.3/tools/clang/docs/LanguageExtensions.html
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| #ifdef __has_builtin
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| #define ABSL_HAVE_BUILTIN(x) __has_builtin(x)
 | |
| #else
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| #define ABSL_HAVE_BUILTIN(x) 0
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| #endif
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| 
 | |
| #if defined(__is_identifier)
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| #define ABSL_INTERNAL_HAS_KEYWORD(x) !(__is_identifier(x))
 | |
| #else
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| #define ABSL_INTERNAL_HAS_KEYWORD(x) 0
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| #endif
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| 
 | |
| // ABSL_HAVE_TLS is defined to 1 when __thread should be supported.
 | |
| // We assume __thread is supported on Linux when compiled with Clang or compiled
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| // against libstdc++ with _GLIBCXX_HAVE_TLS defined.
 | |
| #ifdef ABSL_HAVE_TLS
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| #error ABSL_HAVE_TLS cannot be directly set
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| #elif defined(__linux__) && (defined(__clang__) || defined(_GLIBCXX_HAVE_TLS))
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| #define ABSL_HAVE_TLS 1
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| #endif
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| 
 | |
| // ABSL_HAVE_STD_IS_TRIVIALLY_DESTRUCTIBLE
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| //
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| // Checks whether `std::is_trivially_destructible<T>` is supported.
 | |
| //
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| // Notes: All supported compilers using libc++ support this feature, as does
 | |
| // gcc >= 4.8.1 using libstdc++, and Visual Studio.
 | |
| #ifdef ABSL_HAVE_STD_IS_TRIVIALLY_DESTRUCTIBLE
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| #error ABSL_HAVE_STD_IS_TRIVIALLY_DESTRUCTIBLE cannot be directly set
 | |
| #elif defined(_LIBCPP_VERSION) ||                                        \
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|     (!defined(__clang__) && defined(__GNUC__) && defined(__GLIBCXX__) && \
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|      (__GNUC__ > 4 || (__GNUC__ == 4 && __GNUC_MINOR__ >= 8))) ||        \
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|     defined(_MSC_VER)
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| #define ABSL_HAVE_STD_IS_TRIVIALLY_DESTRUCTIBLE 1
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| #endif
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| 
 | |
| // ABSL_HAVE_STD_IS_TRIVIALLY_CONSTRUCTIBLE
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| //
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| // Checks whether `std::is_trivially_default_constructible<T>` and
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| // `std::is_trivially_copy_constructible<T>` are supported.
 | |
| 
 | |
| // ABSL_HAVE_STD_IS_TRIVIALLY_ASSIGNABLE
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| //
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| // Checks whether `std::is_trivially_copy_assignable<T>` is supported.
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| 
 | |
| // Notes: Clang with libc++ supports these features, as does gcc >= 5.1 with
 | |
| // either libc++ or libstdc++, and Visual Studio (but not NVCC).
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| #if defined(ABSL_HAVE_STD_IS_TRIVIALLY_CONSTRUCTIBLE)
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| #error ABSL_HAVE_STD_IS_TRIVIALLY_CONSTRUCTIBLE cannot be directly set
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| #elif defined(ABSL_HAVE_STD_IS_TRIVIALLY_ASSIGNABLE)
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| #error ABSL_HAVE_STD_IS_TRIVIALLY_ASSIGNABLE cannot directly set
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| #elif (defined(__clang__) && defined(_LIBCPP_VERSION)) ||        \
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|     (!defined(__clang__) && defined(__GNUC__) &&                 \
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|      (__GNUC__ > 7 || (__GNUC__ == 7 && __GNUC_MINOR__ >= 4)) && \
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|      (defined(_LIBCPP_VERSION) || defined(__GLIBCXX__))) ||      \
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|     (defined(_MSC_VER) && !defined(__NVCC__))
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| #define ABSL_HAVE_STD_IS_TRIVIALLY_CONSTRUCTIBLE 1
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| #define ABSL_HAVE_STD_IS_TRIVIALLY_ASSIGNABLE 1
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| #endif
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| 
 | |
| // ABSL_HAVE_SOURCE_LOCATION_CURRENT
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| //
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| // Indicates whether `absl::SourceLocation::current()` will return useful
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| // information in some contexts.
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| #ifndef ABSL_HAVE_SOURCE_LOCATION_CURRENT
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| #if ABSL_INTERNAL_HAS_KEYWORD(__builtin_LINE) && \
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|     ABSL_INTERNAL_HAS_KEYWORD(__builtin_FILE)
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| #define ABSL_HAVE_SOURCE_LOCATION_CURRENT 1
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| #endif
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| #endif
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| 
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| // ABSL_HAVE_THREAD_LOCAL
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| //
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| // Checks whether C++11's `thread_local` storage duration specifier is
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| // supported.
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| #ifdef ABSL_HAVE_THREAD_LOCAL
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| #error ABSL_HAVE_THREAD_LOCAL cannot be directly set
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| #elif defined(__APPLE__)
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| // Notes:
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| // * Xcode's clang did not support `thread_local` until version 8, and
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| //   even then not for all iOS < 9.0.
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| // * Xcode 9.3 started disallowing `thread_local` for 32-bit iOS simulator
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| //   targeting iOS 9.x.
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| // * Xcode 10 moves the deployment target check for iOS < 9.0 to link time
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| //   making __has_feature unreliable there.
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| //
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| // Otherwise, `__has_feature` is only supported by Clang so it has be inside
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| // `defined(__APPLE__)` check.
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| #if __has_feature(cxx_thread_local) && \
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|     !(TARGET_OS_IPHONE && __IPHONE_OS_VERSION_MIN_REQUIRED < __IPHONE_9_0)
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| #define ABSL_HAVE_THREAD_LOCAL 1
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| #endif
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| #else  // !defined(__APPLE__)
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| #define ABSL_HAVE_THREAD_LOCAL 1
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| #endif
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| 
 | |
| // There are platforms for which TLS should not be used even though the compiler
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| // makes it seem like it's supported (Android NDK < r12b for example).
 | |
| // This is primarily because of linker problems and toolchain misconfiguration:
 | |
| // Abseil does not intend to support this indefinitely. Currently, the newest
 | |
| // toolchain that we intend to support that requires this behavior is the
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| // r11 NDK - allowing for a 5 year support window on that means this option
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| // is likely to be removed around June of 2021.
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| // TLS isn't supported until NDK r12b per
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| // https://developer.android.com/ndk/downloads/revision_history.html
 | |
| // Since NDK r16, `__NDK_MAJOR__` and `__NDK_MINOR__` are defined in
 | |
| // <android/ndk-version.h>. For NDK < r16, users should define these macros,
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| // e.g. `-D__NDK_MAJOR__=11 -D__NKD_MINOR__=0` for NDK r11.
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| #if defined(__ANDROID__) && defined(__clang__)
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| #if __has_include(<android/ndk-version.h>)
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| #include <android/ndk-version.h>
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| #endif  // __has_include(<android/ndk-version.h>)
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| #if defined(__ANDROID__) && defined(__clang__) && defined(__NDK_MAJOR__) && \
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|     defined(__NDK_MINOR__) &&                                               \
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|     ((__NDK_MAJOR__ < 12) || ((__NDK_MAJOR__ == 12) && (__NDK_MINOR__ < 1)))
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| #undef ABSL_HAVE_TLS
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| #undef ABSL_HAVE_THREAD_LOCAL
 | |
| #endif
 | |
| #endif  // defined(__ANDROID__) && defined(__clang__)
 | |
| 
 | |
| // ABSL_HAVE_INTRINSIC_INT128
 | |
| //
 | |
| // Checks whether the __int128 compiler extension for a 128-bit integral type is
 | |
| // supported.
 | |
| //
 | |
| // Note: __SIZEOF_INT128__ is defined by Clang and GCC when __int128 is
 | |
| // supported, but we avoid using it in certain cases:
 | |
| // * On Clang:
 | |
| //   * Building using Clang for Windows, where the Clang runtime library has
 | |
| //     128-bit support only on LP64 architectures, but Windows is LLP64.
 | |
| // * On Nvidia's nvcc:
 | |
| //   * nvcc also defines __GNUC__ and __SIZEOF_INT128__, but not all versions
 | |
| //     actually support __int128.
 | |
| #ifdef ABSL_HAVE_INTRINSIC_INT128
 | |
| #error ABSL_HAVE_INTRINSIC_INT128 cannot be directly set
 | |
| #elif defined(__SIZEOF_INT128__)
 | |
| #if (defined(__clang__) && !defined(_WIN32)) || \
 | |
|     (defined(__CUDACC__) && __CUDACC_VER_MAJOR__ >= 9) ||                \
 | |
|     (defined(__GNUC__) && !defined(__clang__) && !defined(__CUDACC__))
 | |
| #define ABSL_HAVE_INTRINSIC_INT128 1
 | |
| #elif defined(__CUDACC__)
 | |
| // __CUDACC_VER__ is a full version number before CUDA 9, and is defined to a
 | |
| // string explaining that it has been removed starting with CUDA 9. We use
 | |
| // nested #ifs because there is no short-circuiting in the preprocessor.
 | |
| // NOTE: `__CUDACC__` could be undefined while `__CUDACC_VER__` is defined.
 | |
| #if __CUDACC_VER__ >= 70000
 | |
| #define ABSL_HAVE_INTRINSIC_INT128 1
 | |
| #endif  // __CUDACC_VER__ >= 70000
 | |
| #endif  // defined(__CUDACC__)
 | |
| #endif  // ABSL_HAVE_INTRINSIC_INT128
 | |
| 
 | |
| // ABSL_HAVE_EXCEPTIONS
 | |
| //
 | |
| // Checks whether the compiler both supports and enables exceptions. Many
 | |
| // compilers support a "no exceptions" mode that disables exceptions.
 | |
| //
 | |
| // Generally, when ABSL_HAVE_EXCEPTIONS is not defined:
 | |
| //
 | |
| // * Code using `throw` and `try` may not compile.
 | |
| // * The `noexcept` specifier will still compile and behave as normal.
 | |
| // * The `noexcept` operator may still return `false`.
 | |
| //
 | |
| // For further details, consult the compiler's documentation.
 | |
| #ifdef ABSL_HAVE_EXCEPTIONS
 | |
| #error ABSL_HAVE_EXCEPTIONS cannot be directly set.
 | |
| 
 | |
| #elif defined(__clang__)
 | |
| 
 | |
| #if __clang_major__ > 3 || (__clang_major__ == 3 && __clang_minor__ >= 6)
 | |
| // Clang >= 3.6
 | |
| #if __has_feature(cxx_exceptions)
 | |
| #define ABSL_HAVE_EXCEPTIONS 1
 | |
| #endif  // __has_feature(cxx_exceptions)
 | |
| #else
 | |
| // Clang < 3.6
 | |
| // http://releases.llvm.org/3.6.0/tools/clang/docs/ReleaseNotes.html#the-exceptions-macro
 | |
| #if defined(__EXCEPTIONS) && __has_feature(cxx_exceptions)
 | |
| #define ABSL_HAVE_EXCEPTIONS 1
 | |
| #endif  // defined(__EXCEPTIONS) && __has_feature(cxx_exceptions)
 | |
| #endif  // __clang_major__ > 3 || (__clang_major__ == 3 && __clang_minor__ >= 6)
 | |
| 
 | |
| // Handle remaining special cases and default to exceptions being supported.
 | |
| #elif !(defined(__GNUC__) && (__GNUC__ < 5) && !defined(__EXCEPTIONS)) &&    \
 | |
|     !(defined(__GNUC__) && (__GNUC__ >= 5) && !defined(__cpp_exceptions)) && \
 | |
|     !(defined(_MSC_VER) && !defined(_CPPUNWIND))
 | |
| #define ABSL_HAVE_EXCEPTIONS 1
 | |
| #endif
 | |
| 
 | |
| // -----------------------------------------------------------------------------
 | |
| // Platform Feature Checks
 | |
| // -----------------------------------------------------------------------------
 | |
| 
 | |
| // Currently supported operating systems and associated preprocessor
 | |
| // symbols:
 | |
| //
 | |
| //   Linux and Linux-derived           __linux__
 | |
| //   Android                           __ANDROID__ (implies __linux__)
 | |
| //   Linux (non-Android)               __linux__ && !__ANDROID__
 | |
| //   Darwin (macOS and iOS)            __APPLE__
 | |
| //   Akaros (http://akaros.org)        __ros__
 | |
| //   Windows                           _WIN32
 | |
| //   NaCL                              __native_client__
 | |
| //   AsmJS                             __asmjs__
 | |
| //   WebAssembly                       __wasm__
 | |
| //   Fuchsia                           __Fuchsia__
 | |
| //
 | |
| // Note that since Android defines both __ANDROID__ and __linux__, one
 | |
| // may probe for either Linux or Android by simply testing for __linux__.
 | |
| 
 | |
| // ABSL_HAVE_MMAP
 | |
| //
 | |
| // Checks whether the platform has an mmap(2) implementation as defined in
 | |
| // POSIX.1-2001.
 | |
| #ifdef ABSL_HAVE_MMAP
 | |
| #error ABSL_HAVE_MMAP cannot be directly set
 | |
| #elif defined(__linux__) || defined(__APPLE__) || defined(__FreeBSD__) ||   \
 | |
|     defined(__ros__) || defined(__native_client__) || defined(__asmjs__) || \
 | |
|     defined(__wasm__) || defined(__Fuchsia__) || defined(__sun) || \
 | |
|     defined(__ASYLO__)
 | |
| #define ABSL_HAVE_MMAP 1
 | |
| #endif
 | |
| 
 | |
| // ABSL_HAVE_PTHREAD_GETSCHEDPARAM
 | |
| //
 | |
| // Checks whether the platform implements the pthread_(get|set)schedparam(3)
 | |
| // functions as defined in POSIX.1-2001.
 | |
| #ifdef ABSL_HAVE_PTHREAD_GETSCHEDPARAM
 | |
| #error ABSL_HAVE_PTHREAD_GETSCHEDPARAM cannot be directly set
 | |
| #elif defined(__linux__) || defined(__APPLE__) || defined(__FreeBSD__) || \
 | |
|     defined(__ros__)
 | |
| #define ABSL_HAVE_PTHREAD_GETSCHEDPARAM 1
 | |
| #endif
 | |
| 
 | |
| // ABSL_HAVE_SCHED_YIELD
 | |
| //
 | |
| // Checks whether the platform implements sched_yield(2) as defined in
 | |
| // POSIX.1-2001.
 | |
| #ifdef ABSL_HAVE_SCHED_YIELD
 | |
| #error ABSL_HAVE_SCHED_YIELD cannot be directly set
 | |
| #elif defined(__linux__) || defined(__ros__) || defined(__native_client__)
 | |
| #define ABSL_HAVE_SCHED_YIELD 1
 | |
| #endif
 | |
| 
 | |
| // ABSL_HAVE_SEMAPHORE_H
 | |
| //
 | |
| // Checks whether the platform supports the <semaphore.h> header and sem_init(3)
 | |
| // family of functions as standardized in POSIX.1-2001.
 | |
| //
 | |
| // Note: While Apple provides <semaphore.h> for both iOS and macOS, it is
 | |
| // explicitly deprecated and will cause build failures if enabled for those
 | |
| // platforms.  We side-step the issue by not defining it here for Apple
 | |
| // platforms.
 | |
| #ifdef ABSL_HAVE_SEMAPHORE_H
 | |
| #error ABSL_HAVE_SEMAPHORE_H cannot be directly set
 | |
| #elif defined(__linux__) || defined(__ros__)
 | |
| #define ABSL_HAVE_SEMAPHORE_H 1
 | |
| #endif
 | |
| 
 | |
| // ABSL_HAVE_ALARM
 | |
| //
 | |
| // Checks whether the platform supports the <signal.h> header and alarm(2)
 | |
| // function as standardized in POSIX.1-2001.
 | |
| #ifdef ABSL_HAVE_ALARM
 | |
| #error ABSL_HAVE_ALARM cannot be directly set
 | |
| #elif defined(__GOOGLE_GRTE_VERSION__)
 | |
| // feature tests for Google's GRTE
 | |
| #define ABSL_HAVE_ALARM 1
 | |
| #elif defined(__GLIBC__)
 | |
| // feature test for glibc
 | |
| #define ABSL_HAVE_ALARM 1
 | |
| #elif defined(_MSC_VER)
 | |
| // feature tests for Microsoft's library
 | |
| #elif defined(__MINGW32__)
 | |
| // mingw32 doesn't provide alarm(2):
 | |
| // https://osdn.net/projects/mingw/scm/git/mingw-org-wsl/blobs/5.2-trunk/mingwrt/include/unistd.h
 | |
| // mingw-w64 provides a no-op implementation:
 | |
| // https://sourceforge.net/p/mingw-w64/mingw-w64/ci/master/tree/mingw-w64-crt/misc/alarm.c
 | |
| #elif defined(__EMSCRIPTEN__)
 | |
| // emscripten doesn't support signals
 | |
| #elif defined(__Fuchsia__)
 | |
| // Signals don't exist on fuchsia.
 | |
| #elif defined(__native_client__)
 | |
| #else
 | |
| // other standard libraries
 | |
| #define ABSL_HAVE_ALARM 1
 | |
| #endif
 | |
| 
 | |
| // ABSL_IS_LITTLE_ENDIAN
 | |
| // ABSL_IS_BIG_ENDIAN
 | |
| //
 | |
| // Checks the endianness of the platform.
 | |
| //
 | |
| // Notes: uses the built in endian macros provided by GCC (since 4.6) and
 | |
| // Clang (since 3.2); see
 | |
| // https://gcc.gnu.org/onlinedocs/cpp/Common-Predefined-Macros.html.
 | |
| // Otherwise, if _WIN32, assume little endian. Otherwise, bail with an error.
 | |
| #if defined(ABSL_IS_BIG_ENDIAN)
 | |
| #error "ABSL_IS_BIG_ENDIAN cannot be directly set."
 | |
| #endif
 | |
| #if defined(ABSL_IS_LITTLE_ENDIAN)
 | |
| #error "ABSL_IS_LITTLE_ENDIAN cannot be directly set."
 | |
| #endif
 | |
| 
 | |
| #if (defined(__BYTE_ORDER__) && defined(__ORDER_LITTLE_ENDIAN__) && \
 | |
|      __BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__)
 | |
| #define ABSL_IS_LITTLE_ENDIAN 1
 | |
| #elif defined(__BYTE_ORDER__) && defined(__ORDER_BIG_ENDIAN__) && \
 | |
|     __BYTE_ORDER__ == __ORDER_BIG_ENDIAN__
 | |
| #define ABSL_IS_BIG_ENDIAN 1
 | |
| #elif defined(_WIN32)
 | |
| #define ABSL_IS_LITTLE_ENDIAN 1
 | |
| #else
 | |
| #error "absl endian detection needs to be set up for your compiler"
 | |
| #endif
 | |
| 
 | |
| // macOS 10.13 and iOS 10.11 don't let you use <any>, <optional>, or <variant>
 | |
| // even though the headers exist and are publicly noted to work.  See
 | |
| // https://github.com/abseil/abseil-cpp/issues/207 and
 | |
| // https://developer.apple.com/documentation/xcode_release_notes/xcode_10_release_notes
 | |
| // libc++ spells out the availability requirements in the file
 | |
| // llvm-project/libcxx/include/__config via the #define
 | |
| // _LIBCPP_AVAILABILITY_BAD_OPTIONAL_ACCESS.
 | |
| #if defined(__APPLE__) && defined(_LIBCPP_VERSION) && \
 | |
|   ((defined(__ENVIRONMENT_MAC_OS_X_VERSION_MIN_REQUIRED__) && \
 | |
|    __ENVIRONMENT_MAC_OS_X_VERSION_MIN_REQUIRED__ < 101400) || \
 | |
|   (defined(__ENVIRONMENT_IPHONE_OS_VERSION_MIN_REQUIRED__) && \
 | |
|    __ENVIRONMENT_IPHONE_OS_VERSION_MIN_REQUIRED__ < 120000) || \
 | |
|   (defined(__ENVIRONMENT_WATCH_OS_VERSION_MIN_REQUIRED__) && \
 | |
|    __ENVIRONMENT_WATCH_OS_VERSION_MIN_REQUIRED__ < 120000) || \
 | |
|   (defined(__ENVIRONMENT_TV_OS_VERSION_MIN_REQUIRED__) && \
 | |
|    __ENVIRONMENT_TV_OS_VERSION_MIN_REQUIRED__ < 50000))
 | |
| #define ABSL_INTERNAL_APPLE_CXX17_TYPES_UNAVAILABLE 1
 | |
| #else
 | |
| #define ABSL_INTERNAL_APPLE_CXX17_TYPES_UNAVAILABLE 0
 | |
| #endif
 | |
| 
 | |
| // ABSL_HAVE_STD_ANY
 | |
| //
 | |
| // Checks whether C++17 std::any is available by checking whether <any> exists.
 | |
| #ifdef ABSL_HAVE_STD_ANY
 | |
| #error "ABSL_HAVE_STD_ANY cannot be directly set."
 | |
| #endif
 | |
| 
 | |
| #ifdef __has_include
 | |
| #if __has_include(<any>) && __cplusplus >= 201703L && \
 | |
|     !ABSL_INTERNAL_APPLE_CXX17_TYPES_UNAVAILABLE
 | |
| #define ABSL_HAVE_STD_ANY 1
 | |
| #endif
 | |
| #endif
 | |
| 
 | |
| // ABSL_HAVE_STD_OPTIONAL
 | |
| //
 | |
| // Checks whether C++17 std::optional is available.
 | |
| #ifdef ABSL_HAVE_STD_OPTIONAL
 | |
| #error "ABSL_HAVE_STD_OPTIONAL cannot be directly set."
 | |
| #endif
 | |
| 
 | |
| #ifdef __has_include
 | |
| #if __has_include(<optional>) && __cplusplus >= 201703L && \
 | |
|     !ABSL_INTERNAL_APPLE_CXX17_TYPES_UNAVAILABLE
 | |
| #define ABSL_HAVE_STD_OPTIONAL 1
 | |
| #endif
 | |
| #endif
 | |
| 
 | |
| // ABSL_HAVE_STD_VARIANT
 | |
| //
 | |
| // Checks whether C++17 std::variant is available.
 | |
| #ifdef ABSL_HAVE_STD_VARIANT
 | |
| #error "ABSL_HAVE_STD_VARIANT cannot be directly set."
 | |
| #endif
 | |
| 
 | |
| #ifdef __has_include
 | |
| #if __has_include(<variant>) && __cplusplus >= 201703L && \
 | |
|     !ABSL_INTERNAL_APPLE_CXX17_TYPES_UNAVAILABLE
 | |
| #define ABSL_HAVE_STD_VARIANT 1
 | |
| #endif
 | |
| #endif
 | |
| 
 | |
| // ABSL_HAVE_STD_STRING_VIEW
 | |
| //
 | |
| // Checks whether C++17 std::string_view is available.
 | |
| #ifdef ABSL_HAVE_STD_STRING_VIEW
 | |
| #error "ABSL_HAVE_STD_STRING_VIEW cannot be directly set."
 | |
| #endif
 | |
| 
 | |
| #ifdef __has_include
 | |
| #if __has_include(<string_view>) && __cplusplus >= 201703L
 | |
| #define ABSL_HAVE_STD_STRING_VIEW 1
 | |
| #endif
 | |
| #endif
 | |
| 
 | |
| // For MSVC, `__has_include` is supported in VS 2017 15.3, which is later than
 | |
| // the support for <optional>, <any>, <string_view>, <variant>. So we use
 | |
| // _MSC_VER to check whether we have VS 2017 RTM (when <optional>, <any>,
 | |
| // <string_view>, <variant> is implemented) or higher. Also, `__cplusplus` is
 | |
| // not correctly set by MSVC, so we use `_MSVC_LANG` to check the language
 | |
| // version.
 | |
| // TODO(zhangxy): fix tests before enabling aliasing for `std::any`.
 | |
| #if defined(_MSC_VER) && _MSC_VER >= 1910 && \
 | |
|     ((defined(_MSVC_LANG) && _MSVC_LANG > 201402) || __cplusplus > 201402)
 | |
| // #define ABSL_HAVE_STD_ANY 1
 | |
| #define ABSL_HAVE_STD_OPTIONAL 1
 | |
| #define ABSL_HAVE_STD_VARIANT 1
 | |
| #define ABSL_HAVE_STD_STRING_VIEW 1
 | |
| #endif
 | |
| 
 | |
| // ABSL_USES_STD_ANY
 | |
| //
 | |
| // Indicates whether absl::any is an alias for std::any.
 | |
| #if !defined(ABSL_OPTION_USE_STD_ANY)
 | |
| #error options.h is misconfigured.
 | |
| #elif ABSL_OPTION_USE_STD_ANY == 0 || \
 | |
|     (ABSL_OPTION_USE_STD_ANY == 2 && !defined(ABSL_HAVE_STD_ANY))
 | |
| #undef ABSL_USES_STD_ANY
 | |
| #elif ABSL_OPTION_USE_STD_ANY == 1 || \
 | |
|     (ABSL_OPTION_USE_STD_ANY == 2 && defined(ABSL_HAVE_STD_ANY))
 | |
| #define ABSL_USES_STD_ANY 1
 | |
| #else
 | |
| #error options.h is misconfigured.
 | |
| #endif
 | |
| 
 | |
| // ABSL_USES_STD_OPTIONAL
 | |
| //
 | |
| // Indicates whether absl::optional is an alias for std::optional.
 | |
| #if !defined(ABSL_OPTION_USE_STD_OPTIONAL)
 | |
| #error options.h is misconfigured.
 | |
| #elif ABSL_OPTION_USE_STD_OPTIONAL == 0 || \
 | |
|     (ABSL_OPTION_USE_STD_OPTIONAL == 2 && !defined(ABSL_HAVE_STD_OPTIONAL))
 | |
| #undef ABSL_USES_STD_OPTIONAL
 | |
| #elif ABSL_OPTION_USE_STD_OPTIONAL == 1 || \
 | |
|     (ABSL_OPTION_USE_STD_OPTIONAL == 2 && defined(ABSL_HAVE_STD_OPTIONAL))
 | |
| #define ABSL_USES_STD_OPTIONAL 1
 | |
| #else
 | |
| #error options.h is misconfigured.
 | |
| #endif
 | |
| 
 | |
| // ABSL_USES_STD_VARIANT
 | |
| //
 | |
| // Indicates whether absl::variant is an alias for std::variant.
 | |
| #if !defined(ABSL_OPTION_USE_STD_VARIANT)
 | |
| #error options.h is misconfigured.
 | |
| #elif ABSL_OPTION_USE_STD_VARIANT == 0 || \
 | |
|     (ABSL_OPTION_USE_STD_VARIANT == 2 && !defined(ABSL_HAVE_STD_VARIANT))
 | |
| #undef ABSL_USES_STD_VARIANT
 | |
| #elif ABSL_OPTION_USE_STD_VARIANT == 1 || \
 | |
|     (ABSL_OPTION_USE_STD_VARIANT == 2 && defined(ABSL_HAVE_STD_VARIANT))
 | |
| #define ABSL_USES_STD_VARIANT 1
 | |
| #else
 | |
| #error options.h is misconfigured.
 | |
| #endif
 | |
| 
 | |
| // ABSL_USES_STD_STRING_VIEW
 | |
| //
 | |
| // Indicates whether absl::string_view is an alias for std::string_view.
 | |
| #if !defined(ABSL_OPTION_USE_STD_STRING_VIEW)
 | |
| #error options.h is misconfigured.
 | |
| #elif ABSL_OPTION_USE_STD_STRING_VIEW == 0 || \
 | |
|     (ABSL_OPTION_USE_STD_STRING_VIEW == 2 &&  \
 | |
|      !defined(ABSL_HAVE_STD_STRING_VIEW))
 | |
| #undef ABSL_USES_STD_STRING_VIEW
 | |
| #elif ABSL_OPTION_USE_STD_STRING_VIEW == 1 || \
 | |
|     (ABSL_OPTION_USE_STD_STRING_VIEW == 2 &&  \
 | |
|      defined(ABSL_HAVE_STD_STRING_VIEW))
 | |
| #define ABSL_USES_STD_STRING_VIEW 1
 | |
| #else
 | |
| #error options.h is misconfigured.
 | |
| #endif
 | |
| 
 | |
| // In debug mode, MSVC 2017's std::variant throws a EXCEPTION_ACCESS_VIOLATION
 | |
| // SEH exception from emplace for variant<SomeStruct> when constructing the
 | |
| // struct can throw. This defeats some of variant_test and
 | |
| // variant_exception_safety_test.
 | |
| #if defined(_MSC_VER) && _MSC_VER >= 1700 && defined(_DEBUG)
 | |
| #define ABSL_INTERNAL_MSVC_2017_DBG_MODE
 | |
| #endif
 | |
| 
 | |
| // ABSL_INTERNAL_MANGLED_NS
 | |
| // ABSL_INTERNAL_MANGLED_BACKREFERENCE
 | |
| //
 | |
| // Internal macros for building up mangled names in our internal fork of CCTZ.
 | |
| // This implementation detail is only needed and provided for the MSVC build.
 | |
| //
 | |
| // These macros both expand to string literals.  ABSL_INTERNAL_MANGLED_NS is
 | |
| // the mangled spelling of the `absl` namespace, and
 | |
| // ABSL_INTERNAL_MANGLED_BACKREFERENCE is a back-reference integer representing
 | |
| // the proper count to skip past the CCTZ fork namespace names.  (This number
 | |
| // is one larger when there is an inline namespace name to skip.)
 | |
| #if defined(_MSC_VER)
 | |
| #if ABSL_OPTION_USE_INLINE_NAMESPACE == 0
 | |
| #define ABSL_INTERNAL_MANGLED_NS "absl"
 | |
| #define ABSL_INTERNAL_MANGLED_BACKREFERENCE "5"
 | |
| #else
 | |
| #define ABSL_INTERNAL_MANGLED_NS \
 | |
|   ABSL_INTERNAL_TOKEN_STR(ABSL_OPTION_INLINE_NAMESPACE_NAME) "@absl"
 | |
| #define ABSL_INTERNAL_MANGLED_BACKREFERENCE "6"
 | |
| #endif
 | |
| #endif
 | |
| 
 | |
| #undef ABSL_INTERNAL_HAS_KEYWORD
 | |
| 
 | |
| // ABSL_DLL
 | |
| //
 | |
| // When building Abseil as a DLL, this macro expands to `__declspec(dllexport)`
 | |
| // so we can annotate symbols appropriately as being exported. When used in
 | |
| // headers consuming a DLL, this macro expands to `__declspec(dllimport)` so
 | |
| // that consumers know the symbol is defined inside the DLL. In all other cases,
 | |
| // the macro expands to nothing.
 | |
| #if defined(_MSC_VER)
 | |
| #if defined(ABSL_BUILD_DLL)
 | |
| #define ABSL_DLL __declspec(dllexport)
 | |
| #elif defined(ABSL_CONSUME_DLL)
 | |
| #define ABSL_DLL __declspec(dllimport)
 | |
| #else
 | |
| #define ABSL_DLL
 | |
| #endif
 | |
| #else
 | |
| #define ABSL_DLL
 | |
| #endif  // defined(_MSC_VER)
 | |
| 
 | |
| #endif  // ABSL_BASE_CONFIG_H_
 |