Add std::index_sequence for C++11

Will be required for nasal::Ghost
This commit is contained in:
Thomas Geymayer 2017-12-22 08:49:21 +01:00
parent ab1e2d49ab
commit 52b8f60953
5 changed files with 156 additions and 9 deletions

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@ -135,6 +135,16 @@ include (DetectArch)
# keep the compatability link option as the default
option(OSG_FSTREAM_EXPORT_FIXED "Set to ON if the osgDB fstream export patch is applied" OFF)
if (CMAKE_COMPILER_IS_GNUCXX OR CLANG)
if (CMAKE_VERSION VERSION_LESS 3.1)
set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -std=c++${CMAKE_CXX_STANDARD}")
elseif (CMAKE_VERSION VERSION_LESS 3.8)
# policy CMP0067 (try_compile does not honor CMAKE_CXX_STANDARD)
set(CMAKE_REQUIRED_FLAGS "${CMAKE_REQUIRED_FLAGS} -std=c++${CMAKE_CXX_STANDARD}")
endif()
endif()
if (MSVC)
GET_FILENAME_COMPONENT(PARENT_DIR ${PROJECT_BINARY_DIR} PATH)
if (CMAKE_CL_64)
@ -382,10 +392,6 @@ if(CMAKE_COMPILER_IS_GNUCXX)
set(WARNING_FLAGS_CXX "-Wall -fPIC")
set(WARNING_FLAGS_C "-Wall -fPIC")
if (CMAKE_VERSION VERSION_LESS 3.1)
set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -std=c++11")
endif()
if(CMAKE_CXX_COMPILER_VERSION VERSION_LESS 4.4)
message(WARNING "GCC 4.4 will be required soon, please upgrade")
endif()
@ -413,10 +419,6 @@ if (CLANG)
# fix Boost compilation :(
set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -stdlib=libc++")
if (CMAKE_VERSION VERSION_LESS 3.1)
set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -std=c++11")
endif()
if(ENABLE_SIMD)
if (X86 OR X86_64)
set(CMAKE_C_FLAGS_RELEASE "-O3 -msse2 -mfpmath=sse")
@ -489,6 +491,14 @@ set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} ${WARNING_FLAGS_C} ${MSVC_FLAGS}")
set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} ${WARNING_FLAGS_CXX} ${MSVC_FLAGS} ${BOOST_CXX_FLAGS}")
set(CMAKE_EXE_LINKER_FLAGS "${CMAKE_EXE_LINKER_FLAGS} ${MSVC_LD_FLAGS}")
check_cxx_source_compiles("
#include <utility>
#include <type_traits>
std::make_index_sequence<0> t;
int main() { return 0; }"
HAVE_STD_INDEX_SEQUENCE
)
# use BEFORE to ensure local directories are used first,
# ahead of system-installed libs
include_directories(BEFORE ${PROJECT_BINARY_DIR}/simgear)

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@ -56,6 +56,10 @@ add_executable(test_CSSBorder CSSBorder_test.cxx)
add_test(CSSBorder ${EXECUTABLE_OUTPUT_PATH}/test_CSSBorder)
target_link_libraries(test_CSSBorder ${TEST_LIBS})
add_executable(test_integer_sequence integer_sequence_test.cxx)
add_test(integer_sequence ${EXECUTABLE_OUTPUT_PATH}/test_integer_sequence)
target_link_libraries(test_integer_sequence ${TEST_LIBS})
add_executable(test_tabbed_values tabbed_values_test.cxx)
add_test(tabbed_values ${EXECUTABLE_OUTPUT_PATH}/test_tabbed_values)
target_link_libraries(test_tabbed_values ${TEST_LIBS})

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@ -0,0 +1,86 @@
///@file
/// Metaprogramming Integer sequence (Is in C++14 but not C++11)
//
// Copyright (C) 2017 Thomas Geymayer <tomgey@gmail.com>
//
// This library is free software; you can redistribute it and/or
// modify it under the terms of the GNU Library General Public
// License as published by the Free Software Foundation; either
// version 2 of the License, or (at your option) any later version.
//
// This library is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
// Library General Public License for more details.
//
// You should have received a copy of the GNU Library General Public
// License along with this library; if not, write to the Free Software
// Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA
#ifndef SIMGEAR_MISC_INTEGER_SEQUENCE_HXX_
#define SIMGEAR_MISC_INTEGER_SEQUENCE_HXX_
#include <utility>
#include <type_traits>
#ifndef HAVE_STD_INDEX_SEQUENCE
# include <cstddef>
namespace std
{
template<class T, T... Ints>
struct integer_sequence
{
static_assert(
std::is_integral<T>::value,
"std::integer_sequence can only be instantiated with an an integral type"
);
typedef T value_type;
static constexpr size_t size() noexcept { return sizeof...(Ints); }
};
}
namespace simgear { namespace detail
{
template<class T, class Seq, T El>
struct append;
template<class T, T ... Ints, T Int>
struct append<T, std::integer_sequence<T, Ints...>, Int>
{
using type = std::integer_sequence<T, Ints..., Int>;
};
template<class T, std::size_t N>
struct sequence_gen
{
using type =
typename append<T, typename sequence_gen<T, N - 1>::type, N - 1>::type;
};
template<class T>
struct sequence_gen<T, 0>
{
using type = std::integer_sequence<T>;
};
}}
namespace std
{
template<size_t... Ints>
using index_sequence = integer_sequence<size_t, Ints...>;
template<class T, size_t N>
using make_integer_sequence =
typename simgear::detail::sequence_gen<T, N>::type;
template<size_t N>
using make_index_sequence = make_integer_sequence<size_t, N>;
template<class... T>
using index_sequence_for = make_index_sequence<sizeof...(T)>;
}
#endif
#endif /* SIMGEAR_MISC_INTEGER_SEQUENCE_HXX_ */

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@ -0,0 +1,47 @@
#include "integer_sequence.hxx"
#include <iostream>
template<class T>
void print(const T& v, std::size_t i)
{
std::cout << "arg #" << i << ": '" << v << "', ";
}
template<typename ... Args, std::size_t ... Is>
void doIt_impl(Args ... args, std::index_sequence<Is...>)
{
std::initializer_list<char>{(print(args, Is), '0')...};
}
template<typename ... Args>
void doIt(Args ... args)
{
static_assert(sizeof...(Args) == std::index_sequence_for<Args...>::size(), "");
doIt_impl<Args...>(args..., std::index_sequence_for<Args...>{});
}
int main(int argc, char* argv[])
{
static_assert(std::is_same<std::integer_sequence<char>::value_type, char>::value, "");
static_assert(std::is_same<std::integer_sequence<long long>::value_type, long long>::value, "");
static_assert(std::is_same<std::index_sequence<>::value_type, std::size_t>::value, "");
static_assert(std::is_same<std::make_index_sequence<0>, std::index_sequence<>>::value, "");
static_assert(std::is_same<std::make_index_sequence<1>, std::index_sequence<0>>::value, "");
static_assert(std::is_same<std::make_index_sequence<2>, std::index_sequence<0, 1>>::value, "");
static_assert(std::is_same<std::make_index_sequence<3>, std::index_sequence<0, 1, 2>>::value, "");
static_assert(std::is_same<std::make_index_sequence<4>, std::index_sequence<0, 1, 2, 3>>::value, "");
static_assert(std::is_same<std::make_index_sequence<5>, std::index_sequence<0, 1, 2, 3, 4>>::value, "");
static_assert(std::is_same<std::make_index_sequence<6>, std::index_sequence<0, 1, 2, 3, 4, 5>>::value, "");
static_assert(std::is_same<std::make_index_sequence<7>, std::index_sequence<0, 1, 2, 3, 4, 5, 6>>::value, "");
static_assert(std::is_same<std::make_index_sequence<8>, std::index_sequence<0, 1, 2, 3, 4, 5, 6, 7>>::value, "");
static_assert(std::make_index_sequence<5>::size() == 5, "");
static_assert(std::index_sequence_for<float, int, double>::size() == 3, "");
std::cout << std::make_integer_sequence<int, 5>::size() << std::endl;
doIt(1, 2, 3, "hallo", 3.4, 3.52f);
return 0;
}

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@ -15,7 +15,7 @@
#cmakedefine HAVE_WINDOWS_H
#cmakedefine HAVE_MKDTEMP
#cmakedefine HAVE_AL_EXT_H
#cmakedefine HAVE_STD_INDEX_SEQUENCE
#cmakedefine GCC_ATOMIC_BUILTINS_FOUND