src/google/protobuf/port_def.inc

// Protocol Buffers - Google's data interchange format
// Copyright 2008 Google Inc.  All rights reserved.
// https://developers.google.com/protocol-buffers/
//
// Redistribution and use in source and binary forms, with or without
// modification, are permitted provided that the following conditions are
// met:
//
//     * Redistributions of source code must retain the above copyright
// notice, this list of conditions and the following disclaimer.
//     * Redistributions in binary form must reproduce the above
// copyright notice, this list of conditions and the following disclaimer
// in the documentation and/or other materials provided with the
// distribution.
//     * Neither the name of Google Inc. nor the names of its
// contributors may be used to endorse or promote products derived from
// this software without specific prior written permission.
//
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

// This file defines common macros that are used in protobuf.
//
// To hide these definitions from the outside world (and to prevent collisions
// if more than one version of protobuf is #included in the same project) you
// must follow this pattern when #including port_def.inc in a header file:
//
// #include "other_header.h"
// #include "message.h"
// // etc.
//
// #include "port_def.inc"  // MUST be last header included
//
// // Definitions for this header.
//
// #include "port_undef.inc"
//
// This is a textual header with no include guard, because we want to
// detect/prohibit anytime it is #included twice without a corresponding
// #undef.

// These macros are private and should always be
// ::util::RetrieveErrorSpace(*this) headers. If any of these errors fire, you
// should either properly #include port_undef.h at the end of your header that
// #includes port.h, or don't #include port.h twice in a .cc file.
#ifdef PROTOBUF_NAMESPACE
#error PROTOBUF_NAMESPACE was previously defined
#endif
#ifdef PROTOBUF_NAMESPACE_ID
#error PROTOBUF_NAMESPACE_ID was previously defined
#endif
#ifdef PROTOBUF_ALWAYS_INLINE
#error PROTOBUF_ALWAYS_INLINE was previously defined
#endif
#ifdef PROTOBUF_COLD
#error PROTOBUF_COLD was previously defined
#endif
#ifdef PROTOBUF_NOINLINE
#error PROTOBUF_NOINLINE was previously defined
#endif
#ifdef PROTOBUF_SECTION_VARIABLE
#error PROTOBUF_SECTION_VARIABLE was previously defined
#endif
#ifdef PROTOBUF_DEPRECATED
#error PROTOBUF_DEPRECATED was previously defined
#endif
#ifdef PROTOBUF_DEPRECATED_MSG
#error PROTOBUF_DEPRECATED_MSG was previously defined
#endif
#ifdef PROTOBUF_FUNC_ALIGN
#error PROTOBUF_FUNC_ALIGN was previously defined
#endif
#ifdef PROTOBUF_RETURNS_NONNULL
#error PROTOBUF_RETURNS_NONNULL was previously defined
#endif
#ifdef PROTOBUF_ATTRIBUTE_REINITIALIZES
#error PROTOBUF_ATTRIBUTE_REINITIALIZES was previously defined
#endif
#ifdef PROTOBUF_RTTI
#error PROTOBUF_RTTI was previously defined
#endif
#ifdef PROTOBUF_VERSION
#error PROTOBUF_VERSION was previously defined
#endif
#ifdef PROTOBUF_VERSION_SUFFIX
#error PROTOBUF_VERSION_SUFFIX was previously defined
#endif
#ifdef PROTOBUF_MIN_HEADER_VERSION_FOR_PROTOC
#error PROTOBUF_MIN_HEADER_VERSION_FOR_PROTOC was previously defined
#endif
#ifdef PROTOBUF_MIN_PROTOC_VERSION
#error PROTOBUF_MIN_PROTOC_VERSION was previously defined
#endif
#ifdef PROTOBUF_PREDICT_TRUE
#error PROTOBUF_PREDICT_TRUE was previously defined
#endif
#ifdef PROTOBUF_PREDICT_FALSE
#error PROTOBUF_PREDICT_FALSE was previously defined
#endif
#ifdef PROTOBUF_FIELD_OFFSET
#error PROTOBUF_FIELD_OFFSET was previously defined
#endif
#ifdef PROTOBUF_LL_FORMAT
#error PROTOBUF_LL_FORMAT was previously defined
#endif
#ifdef PROTOBUF_GUARDED_BY
#error PROTOBUF_GUARDED_BY was previously defined
#endif
#ifdef PROTOBUF_LONGLONG
#error PROTOBUF_LONGLONG was previously defined
#endif
#ifdef PROTOBUF_ULONGLONG
#error PROTOBUF_ULONGLONG was previously defined
#endif
#ifdef PROTOBUF_FALLTHROUGH_INTENDED
#error PROTOBUF_FALLTHROUGH_INTENDED was previously defined
#endif
#ifdef PROTOBUF_EXPORT
#error PROTOBUF_EXPORT was previously defined
#endif
#ifdef PROTOC_EXPORT
#error PROTOC_EXPORT was previously defined
#endif
#ifdef PROTOBUF_MUST_USE_RESULT
#error PROTOBUF_MUST_USE_RESULT was previously defined
#endif
#ifdef PROTOBUF_UNUSED
#error PROTOBUF_UNUSED was previously defined
#endif
#ifdef PROTOBUF_FINAL
#error PROTOBUF_FINAL was previously defined
#endif
#ifdef PROTOBUF_DISABLE_MSVC_UNION_WARNING
#error PROTOBUF_DISABLE_MSVC_UNION_WARNING was previously defined
#endif
#ifdef PROTOBUF_ENABLE_MSVC_UNION_WARNING
#error PROTOBUF_ENABLE_MSVC_UNION_WARNING was previously defined
#endif
#ifdef PROTOBUF_CONSTINIT
#error PROTOBUF_CONSTINIT was previously defined
#endif
#ifdef PROTOBUF_MAYBE_CONSTEXPR
#error PROTOBUF_MAYBE_CONSTEXPR was previously defined
#endif
#ifdef PROTOBUF_ATTRIBUTE_NO_DESTROY
#error PROTOBUF_ATTRIBUTE_NO_DESTROY was previously defined
#endif


#define PROTOBUF_NAMESPACE "google::protobuf"
#define PROTOBUF_NAMESPACE_ID google::protobuf
#define PROTOBUF_NAMESPACE_OPEN \
  namespace google {            \
  namespace protobuf {
#define PROTOBUF_NAMESPACE_CLOSE \
  } /* namespace protobuf */     \
  } /* namespace google */

#if defined(__GNUC__) || defined(__clang__)
#define PROTOBUF_DEPRECATED __attribute__((deprecated))
#define PROTOBUF_DEPRECATED_ENUM __attribute__((deprecated))
#define PROTOBUF_DEPRECATED_MSG(msg) __attribute__((deprecated(msg)))
#elif defined(_MSC_VER)
#define PROTOBUF_DEPRECATED __declspec(deprecated)
#define PROTOBUF_DEPRECATED_ENUM
#define PROTOBUF_DEPRECATED_MSG(msg) __declspec(deprecated(msg))
#endif

#define PROTOBUF_SECTION_VARIABLE(x)
#define PROTOBUF_MUST_USE_RESULT

// ----------------------------------------------------------------------------
// Annotations:  Some parts of the code have been annotated in ways that might
//   be useful to some compilers or tools, but are not supported universally.
//   You can #define these annotations yourself if the default implementation
//   is not right for you.

#ifdef GOOGLE_ATTRIBUTE_ALWAYS_INLINE
#define PROTOBUF_ALWAYS_INLINE GOOGLE_ATTRIBUTE_ALWAYS_INLINE
#else
#if defined(__GNUC__) && \
    (__GNUC__ > 3 || (__GNUC__ == 3 && __GNUC_MINOR__ >= 1))
// For functions we want to force inline.
// Introduced in gcc 3.1.
#define PROTOBUF_ALWAYS_INLINE __attribute__((always_inline))
#else
// Other compilers will have to figure it out for themselves.
#define PROTOBUF_ALWAYS_INLINE
#endif
#endif

#ifdef GOOGLE_ATTRIBUTE_NOINLINE
#define PROTOBUF_NOINLINE GOOGLE_ATTRIBUTE_NOINLINE
#else
#if defined(__GNUC__) && \
    (__GNUC__ > 3 || (__GNUC__ == 3 && __GNUC_MINOR__ >= 1))
// For functions we want to force not inline.
// Introduced in gcc 3.1.
#define PROTOBUF_NOINLINE __attribute__((noinline))
#elif defined(_MSC_VER) && (_MSC_VER >= 1400)
// Seems to have been around since at least Visual Studio 2005
#define PROTOBUF_NOINLINE __declspec(noinline)
#else
// Other compilers will have to figure it out for themselves.
#define PROTOBUF_NOINLINE
#endif
#endif

#ifdef GOOGLE_ATTRIBUTE_FUNC_ALIGN
#define PROTOBUF_FUNC_ALIGN GOOGLE_ATTRIBUTE_FUNC_ALIGN
#else
#if defined(__clang__) || \
    defined(__GNUC__) &&  \
        (__GNUC__ > 4 || (__GNUC__ == 4 && __GNUC_MINOR__ >= 3))
// Function alignment attribute introduced in gcc 4.3
#define PROTOBUF_FUNC_ALIGN(bytes) __attribute__((aligned(bytes)))
#else
#define PROTOBUF_FUNC_ALIGN(bytes)
#endif
#endif

#ifdef GOOGLE_PREDICT_TRUE
#define PROTOBUF_PREDICT_TRUE GOOGLE_PREDICT_TRUE
#else
#ifdef __GNUC__
// Provided at least since GCC 3.0.
#define PROTOBUF_PREDICT_TRUE(x) (__builtin_expect(!!(x), 1))
#else
#define PROTOBUF_PREDICT_TRUE(x) (x)
#endif
#endif

#ifdef GOOGLE_PREDICT_FALSE
#define PROTOBUF_PREDICT_FALSE GOOGLE_PREDICT_FALSE
#else
#ifdef __GNUC__
// Provided at least since GCC 3.0.
#define PROTOBUF_PREDICT_FALSE(x) (__builtin_expect(x, 0))
#else
#define PROTOBUF_PREDICT_FALSE(x) (x)
#endif
#endif

#ifdef GOOGLE_PROTOBUF_ATTRIBUTE_RETURNS_NONNULL
#define PROTOBUF_RETURNS_NONNULL GOOGLE_PROTOBUF_ATTRIBUTE_RETURNS_NONNULL
#else
#if defined(__has_attribute)
#if __has_attribute(returns_nonnull)
#define PROTOBUF_RETURNS_NONNULL __attribute__((returns_nonnull))
#endif
#endif
#endif
#ifndef PROTOBUF_RETURNS_NONNULL
#define PROTOBUF_RETURNS_NONNULL
#endif

#if defined(__has_cpp_attribute)
#if __has_cpp_attribute(clang::reinitializes)
#define PROTOBUF_ATTRIBUTE_REINITIALIZES [[clang::reinitializes]]
#endif
#endif
#ifndef PROTOBUF_ATTRIBUTE_REINITIALIZES
#define PROTOBUF_ATTRIBUTE_REINITIALIZES
#endif

#define PROTOBUF_GUARDED_BY(x)
#define PROTOBUF_COLD

// Copied from ABSL.
#if defined(__clang__) && defined(__has_warning)
#if __has_feature(cxx_attributes) && __has_warning("-Wimplicit-fallthrough")
#define PROTOBUF_FALLTHROUGH_INTENDED [[clang::fallthrough]]
#endif
#elif defined(__GNUC__) && __GNUC__ >= 7
#define PROTOBUF_FALLTHROUGH_INTENDED [[gnu::fallthrough]]
#endif

#ifndef PROTOBUF_FALLTHROUGH_INTENDED
#define PROTOBUF_FALLTHROUGH_INTENDED
#endif

#if defined(__has_cpp_attribute)
#define HAS_ATTRIBUTE(attr) __has_cpp_attribute(attr)
#else
#define HAS_ATTRIBUTE(attr) 0
#endif

#if HAS_ATTRIBUTE(unused) || (defined(__GNUC__) && !defined(__clang__))
#define PROTOBUF_UNUSED __attribute__((__unused__))
#else
#define PROTOBUF_UNUSED
#endif

#undef HAS_ATTRIBUTE

#ifdef _MSC_VER
#define PROTOBUF_LONGLONG(x) x##I64
#define PROTOBUF_ULONGLONG(x) x##UI64
#define PROTOBUF_LL_FORMAT "I64"  // As in printf("%I64d", ...)
#else
// By long long, we actually mean int64.
#define PROTOBUF_LONGLONG(x) x##LL
#define PROTOBUF_ULONGLONG(x) x##ULL
// Used to format real long long integers.
#define PROTOBUF_LL_FORMAT \
  "ll"  // As in "%lld". Note that "q" is poor form also.
#endif


// Shared google3/opensource definitions. //////////////////////////////////////

#define PROTOBUF_VERSION 3014000
#define PROTOBUF_MIN_HEADER_VERSION_FOR_PROTOC 3014000
#define PROTOBUF_MIN_PROTOC_VERSION 3014000
#define PROTOBUF_VERSION_SUFFIX ""

// The minimum library version which works with the current version of the
// headers.
#define GOOGLE_PROTOBUF_MIN_LIBRARY_VERSION 3014000

#if defined(GOOGLE_PROTOBUF_NO_RTTI) && GOOGLE_PROTOBUF_NO_RTTI
#define PROTOBUF_RTTI 0
#elif defined(__has_feature)
// https://clang.llvm.org/docs/LanguageExtensions.html#has-feature-and-has-extension
#define PROTOBUF_RTTI __has_feature(cxx_rtti)
#elif !defined(__cxx_rtti)
// https://en.cppreference.com/w/User:D41D8CD98F/feature_testing_macros#C.2B.2B98
#define PROTOBUF_RTTI 0
#elif defined(__GNUC__) && !defined(__GXX_RTTI)
#https:  // gcc.gnu.org/onlinedocs/cpp/Common-Predefined-Macros.html
#define PROTOBUF_RTTI 0
#else
#define PROTOBUF_RTTI 1
#endif

// Returns the offset of the given field within the given aggregate type.
// This is equivalent to the ANSI C offsetof() macro.  However, according
// to the C++ standard, offsetof() only works on POD types, and GCC
// enforces this requirement with a warning.  In practice, this rule is
// unnecessarily strict; there is probably no compiler or platform on
// which the offsets of the direct fields of a class are non-constant.
// Fields inherited from superclasses *can* have non-constant offsets,
// but that's not what this macro will be used for.
#if defined(__clang__)
// For Clang we use __builtin_offsetof() and suppress the warning,
// to avoid Control Flow Integrity and UBSan vptr sanitizers from
// crashing while trying to validate the invalid reinterpet_casts.
#define PROTOBUF_FIELD_OFFSET(TYPE, FIELD)                   \
  _Pragma("clang diagnostic push")                           \
  _Pragma("clang diagnostic ignored \"-Winvalid-offsetof\"") \
  __builtin_offsetof(TYPE, FIELD)                            \
  _Pragma("clang diagnostic pop")
#elif defined(__GNUC__) && \
          (__GNUC__ > 4 || (__GNUC__ == 4 && __GNUC_MINOR__ >= 8))
#define PROTOBUF_FIELD_OFFSET(TYPE, FIELD) __builtin_offsetof(TYPE, FIELD)
#else  // defined(__clang__)
// Note that we calculate relative to the pointer value 16 here since if we
// just use zero, GCC complains about dereferencing a NULL pointer.  We
// choose 16 rather than some other number just in case the compiler would
// be confused by an unaligned pointer.
#define PROTOBUF_FIELD_OFFSET(TYPE, FIELD)                                \
  static_cast< ::google::protobuf::uint32>(reinterpret_cast<const char*>(                   \
                             &reinterpret_cast<const TYPE*>(16)->FIELD) - \
                         reinterpret_cast<const char*>(16))
#endif

#if defined(PROTOBUF_USE_DLLS)
#if defined(_MSC_VER)
#ifdef LIBPROTOBUF_EXPORTS
#define PROTOBUF_EXPORT __declspec(dllexport)
#define PROTOBUF_EXPORT_TEMPLATE_DECLARE
#define PROTOBUF_EXPORT_TEMPLATE_DEFINE __declspec(dllexport)
#else
#define PROTOBUF_EXPORT __declspec(dllimport)
#define PROTOBUF_EXPORT_TEMPLATE_DECLARE
#define PROTOBUF_EXPORT_TEMPLATE_DEFINE __declspec(dllimport)
#endif
#ifdef LIBPROTOC_EXPORTS
#define PROTOC_EXPORT __declspec(dllexport)
#else
#define PROTOC_EXPORT __declspec(dllimport)
#endif
#else  // defined(_MSC_VER)
#ifdef LIBPROTOBUF_EXPORTS
#define PROTOBUF_EXPORT __attribute__((visibility("default")))
#define PROTOBUF_EXPORT_TEMPLATE_DECLARE __attribute__((visibility("default")))
#define PROTOBUF_EXPORT_TEMPLATE_DEFINE
#else
#define PROTOBUF_EXPORT
#define PROTOBUF_EXPORT_TEMPLATE_DECLARE
#define PROTOBUF_EXPORT_TEMPLATE_DEFINE
#endif
#ifdef LIBPROTOC_EXPORTS
#define PROTOC_EXPORT __attribute__((visibility("default")))
#else
#define PROTOC_EXPORT
#endif
#endif
#else  // defined(PROTOBUF_USE_DLLS)
#define PROTOBUF_EXPORT
#define PROTOC_EXPORT
#define PROTOBUF_EXPORT_TEMPLATE_DECLARE
#define PROTOBUF_EXPORT_TEMPLATE_DEFINE
#endif

// Windows declares several inconvenient macro names.  We #undef them and then
// restore them in port_undef.inc.
#ifdef _MSC_VER
#pragma push_macro("CREATE_NEW")
#undef CREATE_NEW
#pragma push_macro("DOUBLE_CLICK")
#undef DOUBLE_CLICK
#pragma push_macro("ERROR")
#undef ERROR
#pragma push_macro("ERROR_BUSY")
#undef ERROR_BUSY
#pragma push_macro("ERROR_NOT_FOUND")
#undef ERROR_NOT_FOUND
#pragma push_macro("GetMessage")
#undef GetMessage
#pragma push_macro("IGNORE")
#undef IGNORE
#pragma push_macro("IN")
#undef IN
#pragma push_macro("INPUT_KEYBOARD")
#undef INPUT_KEYBOARD
#pragma push_macro("NO_ERROR")
#undef NO_ERROR
#pragma push_macro("OUT")
#undef OUT
#pragma push_macro("OPTIONAL")
#undef OPTIONAL
#pragma push_macro("min")
#undef min
#pragma push_macro("max")
#undef max
#pragma push_macro("NEAR")
#undef NEAR
#pragma push_macro("NO_DATA")
#undef NO_DATA
#pragma push_macro("REASON_UNKNOWN")
#undef REASON_UNKNOWN
#pragma push_macro("SERVICE_DISABLED")
#undef SERVICE_DISABLED
#pragma push_macro("SEVERITY_ERROR")
#undef SEVERITY_ERROR
#pragma push_macro("STRICT")
#undef STRICT
#pragma push_macro("timezone")
#undef timezone
#endif  // _MSC_VER

#if defined(__clang__) || defined(__GNUC__) || defined(_MSC_VER)
// Don't let Objective-C Macros interfere with proto identifiers with the same 
// name.
#pragma push_macro("DEBUG")
#undef DEBUG
#pragma push_macro("TRUE")
#undef TRUE
#pragma push_macro("FALSE")
#undef FALSE
#endif // defined(__clang__) || defined(__GNUC__) || defined(_MSC_VER)

#if defined(__clang__)
#pragma clang diagnostic push
// TODO(gerbens) ideally we cleanup the code. But a cursory try shows many
// violations. So let's ignore for now.
#pragma clang diagnostic ignored "-Wshorten-64-to-32"
#elif defined(__GNUC__)
// GCC does not allow disabling diagnostics within an expression:
// https://gcc.gnu.org/bugzilla/show_bug.cgi?id=60875, so we disable this one
// globally even though it's only used for PROTOBUF_FIELD_OFFSET.
#pragma GCC diagnostic push
#pragma GCC diagnostic ignored "-Winvalid-offsetof"
#endif

// PROTOBUF_ASSUME(pred) tells the compiler that it can assume pred is true. To
// be safe, we also validate the assumption with a GOOGLE_DCHECK in unoptimized
// builds. The macro does not do anything useful if the compiler does not
// support __builtin_assume.
#ifdef __has_builtin
#if __has_builtin(__builtin_assume)
#define PROTOBUF_ASSUME(pred) \
  GOOGLE_DCHECK(pred);               \
  __builtin_assume(pred)
#else
#define PROTOBUF_ASSUME(pred) GOOGLE_DCHECK(pred)
#endif
#else
#define PROTOBUF_ASSUME(pred) GOOGLE_DCHECK(pred)
#endif

// Specify memory alignment for structs, classes, etc.
// Use like:
//   class PROTOBUF_ALIGNAS(16) MyClass { ... }
//   PROTOBUF_ALIGNAS(16) int array[4];
//
// In most places you can use the C++11 keyword "alignas", which is preferred.
//
// But compilers have trouble mixing __attribute__((...)) syntax with
// alignas(...) syntax.
//
// Doesn't work in clang or gcc:
//   struct alignas(16) __attribute__((packed)) S { char c; };
// Works in clang but not gcc:
//   struct __attribute__((packed)) alignas(16) S2 { char c; };
// Works in clang and gcc:
//   struct alignas(16) S3 { char c; } __attribute__((packed));
//
// There are also some attributes that must be specified *before* a class
// definition: visibility (used for exporting functions/classes) is one of
// these attributes. This means that it is not possible to use alignas() with a
// class that is marked as exported.
#if defined(_MSC_VER)
#define PROTOBUF_ALIGNAS(byte_alignment) __declspec(align(byte_alignment))
#elif defined(__GNUC__)
#define PROTOBUF_ALIGNAS(byte_alignment) \
  __attribute__((aligned(byte_alignment)))
#else
#define PROTOBUF_ALIGNAS(byte_alignment) alignas(byte_alignment)
#endif

#define PROTOBUF_FINAL final

#if defined(_MSC_VER)
#define PROTOBUF_THREAD_LOCAL __declspec(thread)
#else
#define PROTOBUF_THREAD_LOCAL __thread
#endif

// For enabling message owned arena, one major blocker is semantic change from
// moving to copying when there is ownership transfer (e.g., move ctor, swap,
// set allocated, release). This change not only causes performance regression
// but also breaks users code (e.g., dangling reference). For top-level
// messages, since it owns the arena, we can mitigate the issue by transferring
// ownership of arena. However, we cannot do that for nested messages. In order
// to tell how many usages of nested messages affected by message owned arena,
// we need to simulate the arena ownership.
// This experiment is purely for the purpose of gathering data. All code guarded
// by this flag is supposed to be removed after this experiment.
// #define PROTOBUF_MESSAGE_OWNED_ARENA_EXPERIMENT

#if defined(__cpp_constinit)
#define PROTOBUF_CONSTINIT constinit
#elif defined(__has_cpp_attribute)
#if __has_cpp_attribute(clang::require_constant_initialization)
#define PROTOBUF_CONSTINIT [[clang::require_constant_initialization]]
#endif
#endif
#ifndef PROTOBUF_CONSTINIT
#define PROTOBUF_CONSTINIT
#endif

// Some constructors can't be constexpr under MSVC, but given that MSVC will not
// do constant initialization of globals anyway we can omit `constexpr` from
// them. These constructors are marked with PROTOBUF_MAYBE_CONSTEXPR
#if defined(_MSC_VER)
#define PROTOBUF_MAYBE_CONSTEXPR
#else
#define PROTOBUF_MAYBE_CONSTEXPR constexpr
#endif

#if _MSC_VER
#define PROTOBUF_DISABLE_MSVC_UNION_WARNING \
  __pragma(warning(push)) \
  __pragma(warning(disable : 4582)) \
  __pragma(warning(disable : 4583))

#define PROTOBUF_ENABLE_MSVC_UNION_WARNING \
  __pragma(warning(pop))
#else
#define PROTOBUF_DISABLE_MSVC_UNION_WARNING
#define PROTOBUF_ENABLE_MSVC_UNION_WARNING
#endif

#if defined(__cpp_constinit)
#define PROTOBUF_CONSTINIT constinit
#elif defined(__has_cpp_attribute)
#if __has_cpp_attribute(clang::require_constant_initialization)
#define PROTOBUF_CONSTINIT [[clang::require_constant_initialization]]
#endif
#endif
#ifndef PROTOBUF_CONSTINIT
#define PROTOBUF_CONSTINIT
#endif

// Some globals with an empty non-trivial destructor are annotated with
// no_destroy for performance reasons. It reduces the cost of these globals in
// non-opt mode and under sanitizers.
#if defined(__has_cpp_attribute)
#if __has_cpp_attribute(clang::no_destroy)
#define PROTOBUF_ATTRIBUTE_NO_DESTROY [[clang::no_destroy]]
#endif
#endif
#if !defined(PROTOBUF_ATTRIBUTE_NO_DESTROY)
#define PROTOBUF_ATTRIBUTE_NO_DESTROY
#endif