| From ccb3eb7b4ff65414a56e2294080885b8966da52b Mon Sep 17 00:00:00 2001 |
| From: Arun Raghavan <git@arunraghavan.net> |
| Date: Tue, 2 Feb 2016 17:01:47 +0530 |
| Subject: [PATCH 2/2] build-sys: Add m4 file for AX_CXX_COMPILE_STDCXX_11 |
| |
| --- |
| m4/ax_cxx_compile_stdcxx.m4 | 558 +++++++++++++++++++++++++++++++++++++++++ |
| m4/ax_cxx_compile_stdcxx_11.m4 | 39 +++ |
| 2 files changed, 597 insertions(+) |
| create mode 100644 m4/ax_cxx_compile_stdcxx.m4 |
| create mode 100644 m4/ax_cxx_compile_stdcxx_11.m4 |
| |
| diff --git a/m4/ax_cxx_compile_stdcxx.m4 b/m4/ax_cxx_compile_stdcxx.m4 |
| new file mode 100644 |
| index 0000000..079e17d |
| --- /dev/null |
| +++ b/m4/ax_cxx_compile_stdcxx.m4 |
| @@ -0,0 +1,558 @@ |
| +# =========================================================================== |
| +# http://www.gnu.org/software/autoconf-archive/ax_cxx_compile_stdcxx.html |
| +# =========================================================================== |
| +# |
| +# SYNOPSIS |
| +# |
| +# AX_CXX_COMPILE_STDCXX(VERSION, [ext|noext], [mandatory|optional]) |
| +# |
| +# DESCRIPTION |
| +# |
| +# Check for baseline language coverage in the compiler for the specified |
| +# version of the C++ standard. If necessary, add switches to CXXFLAGS to |
| +# enable support. VERSION may be '11' (for the C++11 standard) or '14' |
| +# (for the C++14 standard). |
| +# |
| +# The second argument, if specified, indicates whether you insist on an |
| +# extended mode (e.g. -std=gnu++11) or a strict conformance mode (e.g. |
| +# -std=c++11). If neither is specified, you get whatever works, with |
| +# preference for an extended mode. |
| +# |
| +# The third argument, if specified 'mandatory' or if left unspecified, |
| +# indicates that baseline support for the specified C++ standard is |
| +# required and that the macro should error out if no mode with that |
| +# support is found. If specified 'optional', then configuration proceeds |
| +# regardless, after defining HAVE_CXX${VERSION} if and only if a |
| +# supporting mode is found. |
| +# |
| +# LICENSE |
| +# |
| +# Copyright (c) 2008 Benjamin Kosnik <bkoz@redhat.com> |
| +# Copyright (c) 2012 Zack Weinberg <zackw@panix.com> |
| +# Copyright (c) 2013 Roy Stogner <roystgnr@ices.utexas.edu> |
| +# Copyright (c) 2014, 2015 Google Inc.; contributed by Alexey Sokolov <sokolov@google.com> |
| +# Copyright (c) 2015 Paul Norman <penorman@mac.com> |
| +# Copyright (c) 2015 Moritz Klammler <moritz@klammler.eu> |
| +# |
| +# Copying and distribution of this file, with or without modification, are |
| +# permitted in any medium without royalty provided the copyright notice |
| +# and this notice are preserved. This file is offered as-is, without any |
| +# warranty. |
| + |
| +#serial 1 |
| + |
| +dnl This macro is based on the code from the AX_CXX_COMPILE_STDCXX_11 macro |
| +dnl (serial version number 13). |
| + |
| +AC_DEFUN([AX_CXX_COMPILE_STDCXX], [dnl |
| + m4_if([$1], [11], [], |
| + [$1], [14], [], |
| + [$1], [17], [m4_fatal([support for C++17 not yet implemented in AX_CXX_COMPILE_STDCXX])], |
| + [m4_fatal([invalid first argument `$1' to AX_CXX_COMPILE_STDCXX])])dnl |
| + m4_if([$2], [], [], |
| + [$2], [ext], [], |
| + [$2], [noext], [], |
| + [m4_fatal([invalid second argument `$2' to AX_CXX_COMPILE_STDCXX])])dnl |
| + m4_if([$3], [], [ax_cxx_compile_cxx$1_required=true], |
| + [$3], [mandatory], [ax_cxx_compile_cxx$1_required=true], |
| + [$3], [optional], [ax_cxx_compile_cxx$1_required=false], |
| + [m4_fatal([invalid third argument `$3' to AX_CXX_COMPILE_STDCXX])]) |
| + AC_LANG_PUSH([C++])dnl |
| + ac_success=no |
| + AC_CACHE_CHECK(whether $CXX supports C++$1 features by default, |
| + ax_cv_cxx_compile_cxx$1, |
| + [AC_COMPILE_IFELSE([AC_LANG_SOURCE([_AX_CXX_COMPILE_STDCXX_testbody_$1])], |
| + [ax_cv_cxx_compile_cxx$1=yes], |
| + [ax_cv_cxx_compile_cxx$1=no])]) |
| + if test x$ax_cv_cxx_compile_cxx$1 = xyes; then |
| + ac_success=yes |
| + fi |
| + |
| + m4_if([$2], [noext], [], [dnl |
| + if test x$ac_success = xno; then |
| + for switch in -std=gnu++$1 -std=gnu++0x; do |
| + cachevar=AS_TR_SH([ax_cv_cxx_compile_cxx$1_$switch]) |
| + AC_CACHE_CHECK(whether $CXX supports C++$1 features with $switch, |
| + $cachevar, |
| + [ac_save_CXXFLAGS="$CXXFLAGS" |
| + CXXFLAGS="$CXXFLAGS $switch" |
| + AC_COMPILE_IFELSE([AC_LANG_SOURCE([_AX_CXX_COMPILE_STDCXX_testbody_$1])], |
| + [eval $cachevar=yes], |
| + [eval $cachevar=no]) |
| + CXXFLAGS="$ac_save_CXXFLAGS"]) |
| + if eval test x\$$cachevar = xyes; then |
| + CXXFLAGS="$CXXFLAGS $switch" |
| + ac_success=yes |
| + break |
| + fi |
| + done |
| + fi]) |
| + |
| + m4_if([$2], [ext], [], [dnl |
| + if test x$ac_success = xno; then |
| + dnl HP's aCC needs +std=c++11 according to: |
| + dnl http://h21007.www2.hp.com/portal/download/files/unprot/aCxx/PDF_Release_Notes/769149-001.pdf |
| + dnl Cray's crayCC needs "-h std=c++11" |
| + for switch in -std=c++$1 -std=c++0x +std=c++$1 "-h std=c++$1"; do |
| + cachevar=AS_TR_SH([ax_cv_cxx_compile_cxx$1_$switch]) |
| + AC_CACHE_CHECK(whether $CXX supports C++$1 features with $switch, |
| + $cachevar, |
| + [ac_save_CXXFLAGS="$CXXFLAGS" |
| + CXXFLAGS="$CXXFLAGS $switch" |
| + AC_COMPILE_IFELSE([AC_LANG_SOURCE([_AX_CXX_COMPILE_STDCXX_testbody_$1])], |
| + [eval $cachevar=yes], |
| + [eval $cachevar=no]) |
| + CXXFLAGS="$ac_save_CXXFLAGS"]) |
| + if eval test x\$$cachevar = xyes; then |
| + CXXFLAGS="$CXXFLAGS $switch" |
| + ac_success=yes |
| + break |
| + fi |
| + done |
| + fi]) |
| + AC_LANG_POP([C++]) |
| + if test x$ax_cxx_compile_cxx$1_required = xtrue; then |
| + if test x$ac_success = xno; then |
| + AC_MSG_ERROR([*** A compiler with support for C++$1 language features is required.]) |
| + fi |
| + else |
| + if test x$ac_success = xno; then |
| + HAVE_CXX$1=0 |
| + AC_MSG_NOTICE([No compiler with C++$1 support was found]) |
| + else |
| + HAVE_CXX$1=1 |
| + AC_DEFINE(HAVE_CXX$1,1, |
| + [define if the compiler supports basic C++$1 syntax]) |
| + fi |
| + |
| + AC_SUBST(HAVE_CXX$1) |
| + fi |
| +]) |
| + |
| + |
| +dnl Test body for checking C++11 support |
| + |
| +m4_define([_AX_CXX_COMPILE_STDCXX_testbody_11], |
| + _AX_CXX_COMPILE_STDCXX_testbody_new_in_11 |
| +) |
| + |
| + |
| +dnl Test body for checking C++14 support |
| + |
| +m4_define([_AX_CXX_COMPILE_STDCXX_testbody_14], |
| + _AX_CXX_COMPILE_STDCXX_testbody_new_in_11 |
| + _AX_CXX_COMPILE_STDCXX_testbody_new_in_14 |
| +) |
| + |
| + |
| +dnl Tests for new features in C++11 |
| + |
| +m4_define([_AX_CXX_COMPILE_STDCXX_testbody_new_in_11], [[ |
| + |
| +// If the compiler admits that it is not ready for C++11, why torture it? |
| +// Hopefully, this will speed up the test. |
| + |
| +#ifndef __cplusplus |
| + |
| +#error "This is not a C++ compiler" |
| + |
| +#elif __cplusplus < 201103L |
| + |
| +#error "This is not a C++11 compiler" |
| + |
| +#else |
| + |
| +namespace cxx11 |
| +{ |
| + |
| + namespace test_static_assert |
| + { |
| + |
| + template <typename T> |
| + struct check |
| + { |
| + static_assert(sizeof(int) <= sizeof(T), "not big enough"); |
| + }; |
| + |
| + } |
| + |
| + namespace test_final_override |
| + { |
| + |
| + struct Base |
| + { |
| + virtual void f() {} |
| + }; |
| + |
| + struct Derived : public Base |
| + { |
| + virtual void f() override {} |
| + }; |
| + |
| + } |
| + |
| + namespace test_double_right_angle_brackets |
| + { |
| + |
| + template < typename T > |
| + struct check {}; |
| + |
| + typedef check<void> single_type; |
| + typedef check<check<void>> double_type; |
| + typedef check<check<check<void>>> triple_type; |
| + typedef check<check<check<check<void>>>> quadruple_type; |
| + |
| + } |
| + |
| + namespace test_decltype |
| + { |
| + |
| + int |
| + f() |
| + { |
| + int a = 1; |
| + decltype(a) b = 2; |
| + return a + b; |
| + } |
| + |
| + } |
| + |
| + namespace test_type_deduction |
| + { |
| + |
| + template < typename T1, typename T2 > |
| + struct is_same |
| + { |
| + static const bool value = false; |
| + }; |
| + |
| + template < typename T > |
| + struct is_same<T, T> |
| + { |
| + static const bool value = true; |
| + }; |
| + |
| + template < typename T1, typename T2 > |
| + auto |
| + add(T1 a1, T2 a2) -> decltype(a1 + a2) |
| + { |
| + return a1 + a2; |
| + } |
| + |
| + int |
| + test(const int c, volatile int v) |
| + { |
| + static_assert(is_same<int, decltype(0)>::value == true, ""); |
| + static_assert(is_same<int, decltype(c)>::value == false, ""); |
| + static_assert(is_same<int, decltype(v)>::value == false, ""); |
| + auto ac = c; |
| + auto av = v; |
| + auto sumi = ac + av + 'x'; |
| + auto sumf = ac + av + 1.0; |
| + static_assert(is_same<int, decltype(ac)>::value == true, ""); |
| + static_assert(is_same<int, decltype(av)>::value == true, ""); |
| + static_assert(is_same<int, decltype(sumi)>::value == true, ""); |
| + static_assert(is_same<int, decltype(sumf)>::value == false, ""); |
| + static_assert(is_same<int, decltype(add(c, v))>::value == true, ""); |
| + return (sumf > 0.0) ? sumi : add(c, v); |
| + } |
| + |
| + } |
| + |
| + namespace test_noexcept |
| + { |
| + |
| + int f() { return 0; } |
| + int g() noexcept { return 0; } |
| + |
| + static_assert(noexcept(f()) == false, ""); |
| + static_assert(noexcept(g()) == true, ""); |
| + |
| + } |
| + |
| + namespace test_constexpr |
| + { |
| + |
| + template < typename CharT > |
| + unsigned long constexpr |
| + strlen_c_r(const CharT *const s, const unsigned long acc) noexcept |
| + { |
| + return *s ? strlen_c_r(s + 1, acc + 1) : acc; |
| + } |
| + |
| + template < typename CharT > |
| + unsigned long constexpr |
| + strlen_c(const CharT *const s) noexcept |
| + { |
| + return strlen_c_r(s, 0UL); |
| + } |
| + |
| + static_assert(strlen_c("") == 0UL, ""); |
| + static_assert(strlen_c("1") == 1UL, ""); |
| + static_assert(strlen_c("example") == 7UL, ""); |
| + static_assert(strlen_c("another\0example") == 7UL, ""); |
| + |
| + } |
| + |
| + namespace test_rvalue_references |
| + { |
| + |
| + template < int N > |
| + struct answer |
| + { |
| + static constexpr int value = N; |
| + }; |
| + |
| + answer<1> f(int&) { return answer<1>(); } |
| + answer<2> f(const int&) { return answer<2>(); } |
| + answer<3> f(int&&) { return answer<3>(); } |
| + |
| + void |
| + test() |
| + { |
| + int i = 0; |
| + const int c = 0; |
| + static_assert(decltype(f(i))::value == 1, ""); |
| + static_assert(decltype(f(c))::value == 2, ""); |
| + static_assert(decltype(f(0))::value == 3, ""); |
| + } |
| + |
| + } |
| + |
| + namespace test_uniform_initialization |
| + { |
| + |
| + struct test |
| + { |
| + static const int zero {}; |
| + static const int one {1}; |
| + }; |
| + |
| + static_assert(test::zero == 0, ""); |
| + static_assert(test::one == 1, ""); |
| + |
| + } |
| + |
| + namespace test_lambdas |
| + { |
| + |
| + void |
| + test1() |
| + { |
| + auto lambda1 = [](){}; |
| + auto lambda2 = lambda1; |
| + lambda1(); |
| + lambda2(); |
| + } |
| + |
| + int |
| + test2() |
| + { |
| + auto a = [](int i, int j){ return i + j; }(1, 2); |
| + auto b = []() -> int { return '0'; }(); |
| + auto c = [=](){ return a + b; }(); |
| + auto d = [&](){ return c; }(); |
| + auto e = [a, &b](int x) mutable { |
| + const auto identity = [](int y){ return y; }; |
| + for (auto i = 0; i < a; ++i) |
| + a += b--; |
| + return x + identity(a + b); |
| + }(0); |
| + return a + b + c + d + e; |
| + } |
| + |
| + int |
| + test3() |
| + { |
| + const auto nullary = [](){ return 0; }; |
| + const auto unary = [](int x){ return x; }; |
| + using nullary_t = decltype(nullary); |
| + using unary_t = decltype(unary); |
| + const auto higher1st = [](nullary_t f){ return f(); }; |
| + const auto higher2nd = [unary](nullary_t f1){ |
| + return [unary, f1](unary_t f2){ return f2(unary(f1())); }; |
| + }; |
| + return higher1st(nullary) + higher2nd(nullary)(unary); |
| + } |
| + |
| + } |
| + |
| + namespace test_variadic_templates |
| + { |
| + |
| + template <int...> |
| + struct sum; |
| + |
| + template <int N0, int... N1toN> |
| + struct sum<N0, N1toN...> |
| + { |
| + static constexpr auto value = N0 + sum<N1toN...>::value; |
| + }; |
| + |
| + template <> |
| + struct sum<> |
| + { |
| + static constexpr auto value = 0; |
| + }; |
| + |
| + static_assert(sum<>::value == 0, ""); |
| + static_assert(sum<1>::value == 1, ""); |
| + static_assert(sum<23>::value == 23, ""); |
| + static_assert(sum<1, 2>::value == 3, ""); |
| + static_assert(sum<5, 5, 11>::value == 21, ""); |
| + static_assert(sum<2, 3, 5, 7, 11, 13>::value == 41, ""); |
| + |
| + } |
| + |
| + // http://stackoverflow.com/questions/13728184/template-aliases-and-sfinae |
| + // Clang 3.1 fails with headers of libstd++ 4.8.3 when using std::function |
| + // because of this. |
| + namespace test_template_alias_sfinae |
| + { |
| + |
| + struct foo {}; |
| + |
| + template<typename T> |
| + using member = typename T::member_type; |
| + |
| + template<typename T> |
| + void func(...) {} |
| + |
| + template<typename T> |
| + void func(member<T>*) {} |
| + |
| + void test(); |
| + |
| + void test() { func<foo>(0); } |
| + |
| + } |
| + |
| +} // namespace cxx11 |
| + |
| +#endif // __cplusplus >= 201103L |
| + |
| +]]) |
| + |
| + |
| +dnl Tests for new features in C++14 |
| + |
| +m4_define([_AX_CXX_COMPILE_STDCXX_testbody_new_in_14], [[ |
| + |
| +// If the compiler admits that it is not ready for C++14, why torture it? |
| +// Hopefully, this will speed up the test. |
| + |
| +#ifndef __cplusplus |
| + |
| +#error "This is not a C++ compiler" |
| + |
| +#elif __cplusplus < 201402L |
| + |
| +#error "This is not a C++14 compiler" |
| + |
| +#else |
| + |
| +namespace cxx14 |
| +{ |
| + |
| + namespace test_polymorphic_lambdas |
| + { |
| + |
| + int |
| + test() |
| + { |
| + const auto lambda = [](auto&&... args){ |
| + const auto istiny = [](auto x){ |
| + return (sizeof(x) == 1UL) ? 1 : 0; |
| + }; |
| + const int aretiny[] = { istiny(args)... }; |
| + return aretiny[0]; |
| + }; |
| + return lambda(1, 1L, 1.0f, '1'); |
| + } |
| + |
| + } |
| + |
| + namespace test_binary_literals |
| + { |
| + |
| + constexpr auto ivii = 0b0000000000101010; |
| + static_assert(ivii == 42, "wrong value"); |
| + |
| + } |
| + |
| + namespace test_generalized_constexpr |
| + { |
| + |
| + template < typename CharT > |
| + constexpr unsigned long |
| + strlen_c(const CharT *const s) noexcept |
| + { |
| + auto length = 0UL; |
| + for (auto p = s; *p; ++p) |
| + ++length; |
| + return length; |
| + } |
| + |
| + static_assert(strlen_c("") == 0UL, ""); |
| + static_assert(strlen_c("x") == 1UL, ""); |
| + static_assert(strlen_c("test") == 4UL, ""); |
| + static_assert(strlen_c("another\0test") == 7UL, ""); |
| + |
| + } |
| + |
| + namespace test_lambda_init_capture |
| + { |
| + |
| + int |
| + test() |
| + { |
| + auto x = 0; |
| + const auto lambda1 = [a = x](int b){ return a + b; }; |
| + const auto lambda2 = [a = lambda1(x)](){ return a; }; |
| + return lambda2(); |
| + } |
| + |
| + } |
| + |
| + namespace test_digit_seperators |
| + { |
| + |
| + constexpr auto ten_million = 100'000'000; |
| + static_assert(ten_million == 100000000, ""); |
| + |
| + } |
| + |
| + namespace test_return_type_deduction |
| + { |
| + |
| + auto f(int& x) { return x; } |
| + decltype(auto) g(int& x) { return x; } |
| + |
| + template < typename T1, typename T2 > |
| + struct is_same |
| + { |
| + static constexpr auto value = false; |
| + }; |
| + |
| + template < typename T > |
| + struct is_same<T, T> |
| + { |
| + static constexpr auto value = true; |
| + }; |
| + |
| + int |
| + test() |
| + { |
| + auto x = 0; |
| + static_assert(is_same<int, decltype(f(x))>::value, ""); |
| + static_assert(is_same<int&, decltype(g(x))>::value, ""); |
| + return x; |
| + } |
| + |
| + } |
| + |
| +} // namespace cxx14 |
| + |
| +#endif // __cplusplus >= 201402L |
| + |
| +]]) |
| diff --git a/m4/ax_cxx_compile_stdcxx_11.m4 b/m4/ax_cxx_compile_stdcxx_11.m4 |
| new file mode 100644 |
| index 0000000..09db383 |
| --- /dev/null |
| +++ b/m4/ax_cxx_compile_stdcxx_11.m4 |
| @@ -0,0 +1,39 @@ |
| +# ============================================================================ |
| +# http://www.gnu.org/software/autoconf-archive/ax_cxx_compile_stdcxx_11.html |
| +# ============================================================================ |
| +# |
| +# SYNOPSIS |
| +# |
| +# AX_CXX_COMPILE_STDCXX_11([ext|noext], [mandatory|optional]) |
| +# |
| +# DESCRIPTION |
| +# |
| +# Check for baseline language coverage in the compiler for the C++11 |
| +# standard; if necessary, add switches to CXXFLAGS to enable support. |
| +# |
| +# This macro is a convenience alias for calling the AX_CXX_COMPILE_STDCXX |
| +# macro with the version set to C++11. The two optional arguments are |
| +# forwarded literally as the second and third argument respectively. |
| +# Please see the documentation for the AX_CXX_COMPILE_STDCXX macro for |
| +# more information. If you want to use this macro, you also need to |
| +# download the ax_cxx_compile_stdcxx.m4 file. |
| +# |
| +# LICENSE |
| +# |
| +# Copyright (c) 2008 Benjamin Kosnik <bkoz@redhat.com> |
| +# Copyright (c) 2012 Zack Weinberg <zackw@panix.com> |
| +# Copyright (c) 2013 Roy Stogner <roystgnr@ices.utexas.edu> |
| +# Copyright (c) 2014, 2015 Google Inc.; contributed by Alexey Sokolov <sokolov@google.com> |
| +# Copyright (c) 2015 Paul Norman <penorman@mac.com> |
| +# Copyright (c) 2015 Moritz Klammler <moritz@klammler.eu> |
| +# |
| +# Copying and distribution of this file, with or without modification, are |
| +# permitted in any medium without royalty provided the copyright notice |
| +# and this notice are preserved. This file is offered as-is, without any |
| +# warranty. |
| + |
| +#serial 14 |
| + |
| +include([ax_cxx_compile_stdcxx.m4]) |
| + |
| +AC_DEFUN([AX_CXX_COMPILE_STDCXX_11], [AX_CXX_COMPILE_STDCXX([11], [$1], [$2])]) |
| -- |
| 2.12.1 |
| |