config.hpp.in

// Copyright 2016-2023 Francesco Biscani (bluescarni@gmail.com)
//
// This file is part of the mp++ library.
//
// This Source Code Form is subject to the terms of the Mozilla
// Public License v. 2.0. If a copy of the MPL was not distributed
// with this file, You can obtain one at http://mozilla.org/MPL/2.0/.

#ifndef MPPP_CONFIG_HPP
#define MPPP_CONFIG_HPP

// Start of defines instantiated by CMake.
// clang-format off
#define MPPP_VERSION_STRING "@mp++_VERSION@"
#define MPPP_VERSION_MAJOR @mp++_VERSION_MAJOR@
#define MPPP_VERSION_MINOR @mp++_VERSION_MINOR@
#define MPPP_VERSION_PATCH @mp++_VERSION_PATCH@
#define MPPP_ABI_VERSION @MPPP_ABI_VERSION@
#cmakedefine MPPP_GMP_HAVE_MPN_DIVEXACT_1
@MPPP_ENABLE_MPFR@
#cmakedefine MPPP_MPFR_HAVE_MPFR_GET_Q
#cmakedefine MPPP_MPFR_HAVE_MPFR_ROOTN_UI
#cmakedefine MPPP_MPFR_HAVE_MPFR_GAMMA_INC
#cmakedefine MPPP_MPFR_HAVE_MPFR_BETA
#cmakedefine MPPP_MPFR_HAVE_MPFR_ROUNDEVEN
#cmakedefine MPPP_MPFR_HAVE_MPFR_FMODQUO
#cmakedefine MPPP_MPFR_HAVE_MPFR_GET_STR_NDIGITS
@MPPP_ENABLE_ARB@
#cmakedefine MPPP_ARB_HAVE_ACB_AGM
@MPPP_ENABLE_MPC@
@MPPP_ENABLE_QUADMATH@
#cmakedefine MPPP_QUADMATH_HAVE_EXP2Q
#cmakedefine MPPP_QUADMATH_HAVE_LOGBQ
@MPPP_STATIC_BUILD@
#cmakedefine MPPP_WITH_BOOST_S11N
#cmakedefine MPPP_WITH_FMT
// clang-format on
// End of defines instantiated by CMake.

// Setup of the ABI versioning and tagging
// machinery.

#if defined(__GNUC__) || defined(__clang__)

#define MPPP_ABI_TAG_ATTR __attribute__((abi_tag))

#else

#define MPPP_ABI_TAG_ATTR

#endif

// clang-format off
#define MPPP_BEGIN_NAMESPACE                                                                                         \
    namespace mppp                                                                                                   \
    {                                                                                                                \
    inline namespace v@MPPP_ABI_VERSION@ MPPP_ABI_TAG_ATTR                                                           \
    {

#define MPPP_END_NAMESPACE                                                                                           \
    }                                                                                                                \
    }
// clang-format on

// Compiler configuration.

#if defined(__clang__) || defined(__GNUC__) || defined(__INTEL_COMPILER)

// NOTE: GCC, clang (including clang-cl) and the Intel compiler support
// __builtin_expect() and __restrict.
#define mppp_likely(x) __builtin_expect(static_cast<bool>(x), 1)
#define mppp_unlikely(x) __builtin_expect(static_cast<bool>(x), 0)
#define MPPP_RESTRICT __restrict

#elif defined(_MSC_VER)

// NOTE: MSVC (without clang-cl) only supports __restrict.
#define mppp_likely(x) (x)
#define mppp_unlikely(x) (x)
#define MPPP_RESTRICT __restrict

#else

// Otherwise, disable both __builtin_expect() and __restrict.
#define mppp_likely(x) (x)
#define mppp_unlikely(x) (x)
#define MPPP_RESTRICT

#endif

// thread_local configuration:
// - on clang/osx, this seems to be supported since xcode 8:
//   https://stackoverflow.com/questions/28094794/why-does-apple-clang-disallow-c11-thread-local-when-official-clang-supports
//   Note that additional conditions might be needed for iOS, if it ever comes
//   to that. Regarding the versioning, it seems the clang version macros are set
//   to the xcode version:
//   https://stackoverflow.com/questions/19387043/how-can-i-reliably-detect-the-version-of-clang-at-preprocessing-time
//   xcode 8.x is appleclang 8.y:
//   https://en.wikipedia.org/wiki/Xcode#8.x_series
// - at least some MinGW versions have a buggy thread_local implementation. This is shown by testing,
//   and reported in a bunch of places as well:
//   https://sourceforge.net/p/mingw-w64/bugs/445/
//   https://github.com/Alexpux/MINGW-packages/issues/2519
//
// NOTE: at least some early versions of the Intel compiler have a buggy implementation,
// but recent versions seem ok.

#if (defined(__APPLE__) && __clang_major__ < 8) || defined(__MINGW32__)

#define MPPP_MAYBE_TLS

#else

// For the rest, we assume thread_local is available.
#define MPPP_MAYBE_TLS static thread_local
#define MPPP_HAVE_THREAD_LOCAL

#endif

// Concepts setup.
#if defined(__cpp_concepts)

#define MPPP_HAVE_CONCEPTS

// NOTE: GCC < 9 uses the syntax of the concept TS.
#if defined(__GNUC__) && !defined(__clang__) && __GNUC__ < 9

#define MPPP_CONCEPT_DECL concept bool

#else

#define MPPP_CONCEPT_DECL concept

#endif

#endif

// C++ standard setup.
// NOTE: this is necessary because at this time MSVC does not set correctly the
// __cplusplus macro.
#if defined(_MSC_VER)

#define MPPP_CPLUSPLUS _MSVC_LANG

#else

#define MPPP_CPLUSPLUS __cplusplus

#endif

// constexpr setup.
#if MPPP_CPLUSPLUS >= 201402L

#define MPPP_CONSTEXPR_14 constexpr

#else

#define MPPP_CONSTEXPR_14

#endif

#if MPPP_CPLUSPLUS >= 202002L

#define MPPP_CONSTEXPR_20 constexpr

#else

#define MPPP_CONSTEXPR_20

#endif

// Detect if the compiler supports GCC-style 128-bit integers.
// NOTE: we can check int128 on GCC/clang with __SIZEOF_INT128__ apparently:
// http://stackoverflow.com/questions/21886985/what-gcc-versions-support-the-int128-intrinsic-type
// NOTE: clang-cl supports the types, but not all the arithmetic operations on them. Let's disable it for now.
#if ((defined(__clang__) && !defined(_MSC_VER)) || defined(__GNUC__) || defined(__INTEL_COMPILER))                     \
    && defined(__SIZEOF_INT128__)

#define MPPP_HAVE_GCC_INT128

#endif

// Check if we have std::string_view available.
// Older compilers might advertise C++17 support
// without implementing all the necessary library
// components - this is the case with MSVC 2015
// and std::string_view.
#if MPPP_CPLUSPLUS >= 201703L

#if __has_include(<string_view>)

#define MPPP_HAVE_STRING_VIEW

#endif

#endif

// Wrapper for the C++17 [[fallthrough]] attribute.
#if MPPP_CPLUSPLUS >= 201703L

#define MPPP_FALLTHROUGH [[fallthrough]]

#elif !defined(__INTEL_COMPILER) && !defined(__clang__) && defined(__GNUC__) && __GNUC__ >= 7

// On GCC>=7, if we are not using C++17 we can use
// an alternative attribute:
// https://developers.redhat.com/blog/2017/03/10/wimplicit-fallthrough-in-gcc-7/
// This may be supported on some clang versions as well:
// https://reviews.llvm.org/D63260
#define MPPP_FALLTHROUGH [[gnu::fallthrough]]

#else

#define MPPP_FALLTHROUGH void(0)

#endif

// Wrapper for the C++17 [[nodiscard]], [[maybe_unused]] attributes.
#if MPPP_CPLUSPLUS >= 201703L

#define MPPP_NODISCARD [[nodiscard]]
#define MPPP_MAYBE_UNUSED [[maybe_unused]]

#else

#define MPPP_NODISCARD
#define MPPP_MAYBE_UNUSED

#endif

// C++20 constinit.
// NOTE: this seems to be buggy currently on MSVC:
// https://github.com/bluescarni/mppp/issues/291
#if defined(__cpp_constinit) && (!defined(_MSC_VER) || defined(__clang__))

#define MPPP_CONSTINIT constinit

#else

#define MPPP_CONSTINIT

#endif

#if defined(MPPP_WITH_QUADMATH)

// Define the MPPP_FLOAT128_WITH_LONG_DOUBLE name
// if __float128 can interact with long double.

#if defined(__clang__)

#if defined(__apple_build_version__)

// NOTE: according to https://en.wikipedia.org/wiki/Xcode#Toolchain_versions,
// clang 7 starts in Xcode 10.2.
#if __clang_major__ > 10 || (__clang_major__ == 10 && __clang_minor__ >= 2)

#define MPPP_FLOAT128_WITH_LONG_DOUBLE

#endif

#else

// Vanilla clang.
#if __clang_major__ >= 7

#define MPPP_FLOAT128_WITH_LONG_DOUBLE

#endif

#endif

#else

// On non-clang, let's always assume that __float128
// can interact with long double, *unless* we are on
// PowerPC. On such a setup, GCC disables interaction
// between __float128 and long double.
#if !defined(__PPC__)

#define MPPP_FLOAT128_WITH_LONG_DOUBLE

#endif

#endif

#endif

#endif