features.h

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#ifndef LELY_FEATURES_H_
#define LELY_FEATURES_H_
 
#if defined(__STDC_VERSION__) && __STDC_VERSION__ < 199901L
#error This file requires compiler and library support for the ISO C99 standard.
#endif
 
#if defined(__cplusplus) && __cplusplus < 201103L
#error This file requires compiler and library support for the ISO C++11 standard.
#endif
 
#ifdef _MSC_VER
#if _MSC_VER < 1900
#error This file requires Microsoft Visual C++ 2015 or later.
#endif
// Disable warnings about deprecated POSIX functions.
#pragma warning(disable : 4996)
#endif
 
#ifdef _WIN32
// Windows 7 is the minimum supported version.
#if !defined(NTDDI_VERSION) || (NTDDI_VERSION < NTDDI_WIN7)
#undef NTDDI_VERSION
#define NTDDI_VERSION NTDDI_WIN7
#endif
#if !defined(_WIN32_WINNT) || _WIN32_WINNT < _WIN32_WINNT_WIN7
#undef _WIN32_WINNT
#define _WIN32_WINNT _WIN32_WINNT_WIN7
#endif
#if !defined(WINVER) || WINVER < _WIN32_WINNT
#undef WINVER
#define WINVER _WIN32_WINNT
#endif
#ifndef WIN32_LEAN_AND_MEAN
#define WIN32_LEAN_AND_MEAN
#endif
#include <windef.h>
#endif
 
// <limits.h> is guaranteed to be present, even in freestanding environments,
// and will typically include <features.h>, which we need but cannot portably
// include directly.
#include <limits.h>
 
// Include a (platform-specific) header which defines the POSIX feature test
// macros.
#ifdef __GLIBC__
#include <bits/posix_opt.h>
#elif defined(__NEWLIB__)
#include <sys/features.h>
#endif
 
#ifndef CLANG_PREREQ
#if defined(__clang__) && defined(__clang_major__) && defined(__clang_minor__)
#define CLANG_PREREQ(major, minor) \
        ((__clang_major__ << 16) + __clang_minor__ >= ((major) << 16) + (minor))
#else
#define CLANG_PREREQ(major, minor) 0
#endif
#endif
 
#ifndef GNUC_PREREQ
#if defined(__GNUC__) && defined(__GNUC_MINOR__)
#define GNUC_PREREQ(major, minor) \
        ((__GNUC__ << 16) + __GNUC_MINOR__ >= ((major) << 16) + (minor))
#else
#define GNUC_PREREQ(major, minor) 0
#endif
#endif
 
#ifndef __has_attribute
#define __has_attribute(x) 0
#endif
 
#ifndef __has_builtin
#define __has_builtin(x) 0
#endif
 
#ifndef __has_declspec_attribute
#define __has_declspec_attribute(x) 0
#endif
 
#ifndef __has_extension
#define __has_extension __has_feature
#endif
 
#ifndef __has_feature
#define __has_feature(x) 0
#endif
 
#ifndef __has_include
#define __has_include(x) 1
#endif
 
#ifndef __STDC_CONSTANT_MACROS
#define __STDC_CONSTANT_MACROS 1
#endif
 
#ifndef __STDC_LIMIT_MACROS
#define __STDC_LIMIT_MACROS 1
#endif
 
#ifndef __STDC_NO_ATOMICS__
// GCC versions older than 4.9 do not properly advertise the absence of
// <stdatomic.h>.
// clang-format off
#if defined(__cplusplus) || defined(_MSC_VER) \
                || (defined(__GNUC__) && !GNUC_PREREQ(4, 9) \
                                && !defined(__clang__)) \
                || (defined(__clang__) && !__has_extension(c_atomic))
// clang-format on
#define __STDC_NO_ATOMICS__ 1
#endif
#endif
 
#ifndef __STDC_NO_THREADS__
// Although recent versions of Cygwin do provide <threads.h>, it requires
// <machine/_threads.h>, which is missing.
#if defined(__cplusplus) || defined(_MSC_VER) || defined(__CYGWIN__)
#define __STDC_NO_THREADS__ 1
#endif
#endif
 
#ifndef __STDC_NO_VLA__
#if defined(__cplusplus) || defined(_MSC_VER)
#define __STDC_NO_VLA__ 1
#endif
#endif
 
#ifdef __cplusplus
 
#ifndef __cpp_exceptions
#if (defined(_MSC_VER) && _HAS_EXCEPTIONS) \
                || (defined(__GNUC__) && defined(__EXCEPTIONS)) \
                || (defined(__clang__) && __has_feature(cxx_exceptions))
#define __cpp_exceptions __cplusplus
#endif
#endif
 
#ifndef __cpp_rtti
#if (defined(_MSC_VER) && _CPPRTTI) \
                || (defined(__GNUC__) && defined(__GXX_RTTI)) \
                || (defined(__clang__) && __has_feature(cxx_rtti))
#define __cpp_rtti __cplusplus
#endif
#endif
 
#endif // __cplusplus
 
// clang-format off
#if !defined(_Alignas) && !(__STDC_VERSION__ >= 201112L \
                && (GNUC_PREREQ(4, 7) || __has_feature(c_alignas)))
// clang-format on
#if __cplusplus >= 201103L && (GNUC_PREREQ(4, 8) || __has_feature(cxx_alignas))
#define _Alignas alignas
#elif defined(__GNUC__) || __has_attribute(__aligned__)
#define _Alignas(x) __attribute__((__aligned__(x)))
#elif defined(_MSC_VER) || defined(__declspec) \
                || __has_declspec_attribute(align)
#define _Alignas(x) __declspec(align(x))
#else
#define _Alignas(x)
#endif
#endif
 
// clang-format off
#if !defined(_Alignof) && !(__STDC_VERSION__ >= 201112L \
                && (GNUC_PREREQ(4, 7) || __has_feature(c_alignof)))
// clang-format on
#if __cplusplus >= 201103L && (GNUC_PREREQ(4, 8) || __has_feature(cxx_alignof))
#define _Alignof alignof
#elif defined(__GNUC__)
#define _Alignof(x) __alignof__(x)
#elif defined(_MSC_VER)
#define _Alignof(x) __alignof(x)
#else
#include <stddef.h>
#define _Alignof(type)(offsetof(struct { char c; type x; }, x))
#endif
#endif
 
// clang-format off
#if !defined(_Noreturn) && !(__STDC_VERSION__ >= 201112L \
                && (GNUC_PREREQ(4, 7) || CLANG_PREREQ(3, 3)))
// clang-format on
#if defined(__GNUC__) || __has_attribute(__noreturn__)
#define _Noreturn __attribute__((__noreturn__))
#elif defined(_MSC_VER) || defined(__declspec) \
                || __has_declspec_attribute(noreturn)
#define _Noreturn __declspec(noreturn)
#else
#define _Noreturn
#endif
#endif
 
// clang-format off
#if !defined(_Thread_local) && !(__STDC_VERSION__ >= 201112L \
                && (GNUC_PREREQ(4, 7) || __has_feature(c_thread_local)))
// clang-format on
#if __cplusplus >= 201103L \
                && (GNUC_PREREQ(4, 8) || __has_feature(cxx_thread_local))
#define _Thread_local thread_local
#elif defined(__GNUC__)
#define _Thread_local __thread
#elif defined(_MSC_VER) || defined(__declspec) \
                || __has_declspec_attribute(thread)
#define _Thread_local __declspec(thread)
#else
#define _Thread_local
#endif
#endif
 
#ifndef __builtin_expect
#if defined(__GNUC__) || __has_builtin(__builtin_expect)
#else
#define __builtin_expect(exp, c) (exp)
#endif
#endif
 
#ifndef format_printf__
#if defined(__GNUC__) || __has_attribute(__format__)
#ifdef __MINGW32__
#define format_printf__(i, j) \
        __attribute__((__format__(__gnu_printf__, (i), (j))))
#else
#define format_printf__(i, j) __attribute__((__format__(__printf__, (i), (j))))
#endif
#else
#define format_printf__(i, j)
#endif
#endif
 
#ifndef __likely
#define __likely(x) __builtin_expect(!!(x), 1)
#endif
 
#ifndef __unlikely
#define __unlikely(x) __builtin_expect(!!(x), 0)
#endif
 
#ifndef __WORDSIZE
// clang-format off
#if !defined(__ILP32__) && (defined(__LP64__) || defined(_WIN64) \
                || defined(_M_AMD64) || defined(__amd64__) || defined(_M_IA64) \
                || defined(__ia64__) || defined(_M_X64) || defined(__x86_64__) \
                || defined(__aarch64__))
// clang-format on
#define __WORDSIZE 64
#else
#define __WORDSIZE 32
#endif
#endif
 
#ifndef LONG_BIT
#ifdef _WIN32
// long remains 32-bits on 64-bit Windows.
#define LONG_BIT 32
#else
#define LONG_BIT __WORDSIZE
#endif
#endif
 
#define LELY_INGORE_EMPTY_TRANSLATION_UNIT \
        typedef int lely_ignore_empty_translation_unit__;
 
#endif // LELY_FEATURES_H_