| // This file is part of Eigen, a lightweight C++ template library |
| // for linear algebra. |
| // |
| // Copyright (C) 2013 Christian Seiler <christian@iwakd.de> |
| // |
| // 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 EIGEN_CXX11WORKAROUNDS_H |
| #define EIGEN_CXX11WORKAROUNDS_H |
| |
| /* COMPATIBILITY CHECKS |
| * (so users of compilers that are too old get some realistic error messages) |
| */ |
| #if defined(__INTEL_COMPILER) && (__INTEL_COMPILER < 1310) |
| #error Intel Compiler only supports required C++ features since version 13.1. |
| // note that most stuff in principle works with 13.0 but when combining |
| // some features, at some point 13.0 will just fail with an internal assertion |
| #elif defined(__GNUC__) && !defined(__clang__) && !defined(__INTEL_COMPILER) && (__GNUC__ < 4 || (__GNUC__ == 4 && __GNUC_MINOR__ < 6)) |
| // G++ < 4.6 by default will continue processing the source files - even if we use #error to make |
| // it error out. For this reason, we use the pragma to make sure G++ aborts at the first error |
| // it sees. Unfortunately, that is still not our #error directive, but at least the output is |
| // short enough the user has a chance to see that the compiler version is not sufficient for |
| // the funky template mojo we use. |
| #pragma GCC diagnostic error "-Wfatal-errors" |
| #error GNU C++ Compiler (g++) only supports required C++ features since version 4.6. |
| #endif |
| |
| /* Check that the compiler at least claims to support C++11. It might not be sufficient |
| * because the compiler may not implement it correctly, but at least we'll know. |
| */ |
| #if __cplusplus <= 199711L |
| #if defined(__GNUC__) && !defined(__clang__) && !defined(__INTEL_COMPILER) |
| #pragma GCC diagnostic error "-Wfatal-errors" |
| #endif |
| #error This library needs at least a C++11 compliant compiler. If you use g++/clang, please enable the -std=c++11 compiler flag. (-std=c++0x on older versions.) |
| #endif |
| |
| namespace Eigen { |
| |
| // Use std::array as Eigen array |
| template <typename T, std::size_t N> using array = std::array<T, N>; |
| |
| namespace internal { |
| |
| /* std::get is only constexpr in C++14, not yet in C++11 |
| * - libstdc++ from version 4.7 onwards has it nevertheless, |
| * so use that |
| * - libstdc++ older versions: use _M_instance directly |
| * - libc++ all versions so far: use __elems_ directly |
| * - all other libs: use std::get to be portable, but |
| * this may not be constexpr |
| */ |
| #if defined(__GLIBCXX__) && __GLIBCXX__ < 20120322 |
| #define STD_GET_ARR_HACK a._M_instance[I] |
| #elif defined(_LIBCPP_VERSION) |
| #define STD_GET_ARR_HACK a.__elems_[I] |
| #else |
| #define STD_GET_ARR_HACK std::template get<I, T, N>(a) |
| #endif |
| |
| template<std::size_t I, class T, std::size_t N> constexpr inline T& array_get(std::array<T,N>& a) { return (T&) STD_GET_ARR_HACK; } |
| template<std::size_t I, class T, std::size_t N> constexpr inline T&& array_get(std::array<T,N>&& a) { return (T&&) STD_GET_ARR_HACK; } |
| template<std::size_t I, class T, std::size_t N> constexpr inline T const& array_get(std::array<T,N> const& a) { return (T const&) STD_GET_ARR_HACK; } |
| |
| template<std::size_t I, class T> constexpr inline T& array_get(std::vector<T>& a) { return a[I]; } |
| template<std::size_t I, class T> constexpr inline T&& array_get(std::vector<T>&& a) { return a[I]; } |
| template<std::size_t I, class T> constexpr inline T const& array_get(std::vector<T> const& a) { return a[I]; } |
| |
| #undef STD_GET_ARR_HACK |
| |
| template <typename T> struct array_size; |
| template<class T, std::size_t N> struct array_size<const std::array<T,N> > { |
| static const size_t value = N; |
| }; |
| template <typename T> struct array_size; |
| template<class T, std::size_t N> struct array_size<std::array<T,N> > { |
| static const size_t value = N; |
| }; |
| |
| /* Suppose you have a template of the form |
| * template<typename T> struct X; |
| * And you want to specialize it in such a way: |
| * template<typename S1, typename... SN> struct X<Foo<S1, SN...>> { ::: }; |
| * template<> struct X<Foo<>> { ::: }; |
| * This will work in Intel's compiler 13.0, but only to some extent in g++ 4.6, since |
| * g++ can only match templates called with parameter packs if the number of template |
| * arguments is not a fixed size (so inside the first specialization, referencing |
| * X<Foo<Sn...>> will fail in g++). On the other hand, g++ will accept the following: |
| * template<typename S...> struct X<Foo<S...>> { ::: }: |
| * as an additional (!) specialization, which will then only match the empty case. |
| * But Intel's compiler 13.0 won't accept that, it will only accept the empty syntax, |
| * so we have to create a workaround for this. |
| */ |
| #if defined(__GNUC__) && !defined(__INTEL_COMPILER) |
| #define EIGEN_TPL_PP_SPEC_HACK_DEF(mt, n) mt... n |
| #define EIGEN_TPL_PP_SPEC_HACK_DEFC(mt, n) , EIGEN_TPL_PP_SPEC_HACK_DEF(mt, n) |
| #define EIGEN_TPL_PP_SPEC_HACK_USE(n) n... |
| #define EIGEN_TPL_PP_SPEC_HACK_USEC(n) , n... |
| #else |
| #define EIGEN_TPL_PP_SPEC_HACK_DEF(mt, n) |
| #define EIGEN_TPL_PP_SPEC_HACK_DEFC(mt, n) |
| #define EIGEN_TPL_PP_SPEC_HACK_USE(n) |
| #define EIGEN_TPL_PP_SPEC_HACK_USEC(n) |
| #endif |
| |
| } // end namespace internal |
| |
| } // end namespace Eigen |
| |
| #endif // EIGEN_CXX11WORKAROUNDS_H |
| |
| /* |
| * kate: space-indent on; indent-width 2; mixedindent off; indent-mode cstyle; |
| */ |