diff --git a/config/configure b/config/configure index af2f4c79c1..ecee777dfb 100755 --- a/config/configure +++ b/config/configure @@ -2777,13 +2777,13 @@ ac_config_headers="$ac_config_headers include/dcmtk/config/osconfig.h" # # Check for baseline language coverage in the compiler for the specified # version of the C++ standard. If necessary, add switches to CXX and -# CXXCPP to enable support. VERSION may be '11' (for the C++11 standard) -# or '14' (for the C++14 standard). +# CXXCPP to enable support. VERSION may be '11', '14', '17', or '20' for +# the respective C++ standard version. # # The second argument, if specified, indicates whether you insist on an # extended mode (e.g. -std=gnu++11) or a strict conformance mode (e.g. # -std=c++11). If neither is specified, you get whatever works, with -# preference for an extended mode. +# preference for no added switch, and then for an extended mode. # # The third argument, if specified 'mandatory' or if left unspecified, # indicates that baseline support for the specified C++ standard is @@ -2800,14 +2800,25 @@ ac_config_headers="$ac_config_headers include/dcmtk/config/osconfig.h" # Copyright (c) 2014, 2015 Google Inc.; contributed by Alexey Sokolov # Copyright (c) 2015 Paul Norman # Copyright (c) 2015 Moritz Klammler -# Copyright (c) 2016 Krzesimir Nowak +# Copyright (c) 2016, 2018 Krzesimir Nowak +# Copyright (c) 2019 Enji Cooper +# Copyright (c) 2020 Jason Merrill +# Copyright (c) 2021 Joern Heusipp # # 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 7 +#serial 18 + + + + + + + + @@ -11065,7 +11076,7 @@ if ${ac_cv_check_std_namespace+:} false; then : else ac_link_o='${CXX-g++} -o conftest $CXXFLAGS $CPPFLAGS $LDFLAGS conftest.o $LIBS 1>&5' cat > conftest.$ac_ext < @@ -13235,319 +13246,20 @@ ac_compile='$CXX -c $CXXFLAGS $CPPFLAGS conftest.$ac_ext >&5' ac_link='$CXX -o conftest$ac_exeext $CXXFLAGS $CPPFLAGS $LDFLAGS conftest.$ac_ext $LIBS >&5' ac_compiler_gnu=$ac_cv_cxx_compiler_gnu ac_success=no - { $as_echo "$as_me:${as_lineno-$LINENO}: checking whether $CXX supports C++11 features by default" >&5 -$as_echo_n "checking whether $CXX supports C++11 features by default... " >&6; } -if ${ax_cv_cxx_compile_cxx11+:} false; then : - $as_echo_n "(cached) " >&6 -else - cat confdefs.h - <<_ACEOF >conftest.$ac_ext -/* end confdefs.h. */ - - -// 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 - 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 single_type; - typedef check> double_type; - typedef check>> triple_type; - typedef check>>> 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 - { - 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::value == true, ""); - static_assert(is_same::value == false, ""); - static_assert(is_same::value == false, ""); - auto ac = c; - auto av = v; - auto sumi = ac + av + 'x'; - auto sumf = ac + av + 1.0; - static_assert(is_same::value == true, ""); - static_assert(is_same::value == true, ""); - static_assert(is_same::value == true, ""); - static_assert(is_same::value == false, ""); - static_assert(is_same::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 - struct sum; - - template - struct sum - { - static constexpr auto value = N0 + sum::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 - using member = typename T::member_type; - - template - void func(...) {} - - template - void func(member*) {} - - void test(); - - void test() { func(0); } - - } - -} // namespace cxx11 - -#endif // __cplusplus >= 201103L - - - -_ACEOF -if ac_fn_cxx_try_compile "$LINENO"; then : - ax_cv_cxx_compile_cxx11=yes -else - ax_cv_cxx_compile_cxx11=no -fi -rm -f core conftest.err conftest.$ac_objext conftest.$ac_ext -fi -{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $ax_cv_cxx_compile_cxx11" >&5 -$as_echo "$ax_cv_cxx_compile_cxx11" >&6; } - if test x$ax_cv_cxx_compile_cxx11 = xyes; then - ac_success=yes - fi if test x$ac_success = xno; then - for alternative in ${ax_cxx_compile_alternatives}; do - for switch in -std=c++${alternative} +std=c++${alternative} "-h std=c++${alternative}"; do - cachevar=`$as_echo "ax_cv_cxx_compile_cxx11_$switch" | $as_tr_sh` + for alternative in ${ax_cxx_compile_alternatives}; do + for switch in -std=c++${alternative} +std=c++${alternative} "-h std=c++${alternative}" MSVC; do + if test x"$switch" = xMSVC; then + switch=-std:c++${alternative} + cachevar=`$as_echo "ax_cv_cxx_compile_cxx11_${switch}_MSVC" | $as_tr_sh` + else + cachevar=`$as_echo "ax_cv_cxx_compile_cxx11_$switch" | $as_tr_sh` + fi { $as_echo "$as_me:${as_lineno-$LINENO}: checking whether $CXX supports C++11 features with $switch" >&5 $as_echo_n "checking whether $CXX supports C++11 features with $switch... " >&6; } if eval \${$cachevar+:} false; then : @@ -13566,7 +13278,11 @@ else #error "This is not a C++ compiler" -#elif __cplusplus < 201103L +// MSVC always sets __cplusplus to 199711L in older versions; newer versions +// only set it correctly if /Zc:__cplusplus is specified as well as a +// /std:c++NN switch: +// https://devblogs.microsoft.com/cppblog/msvc-now-correctly-reports-__cplusplus/ +#elif __cplusplus < 201103L && !defined _MSC_VER #error "This is not a C++11 compiler" @@ -13591,11 +13307,13 @@ namespace cxx11 struct Base { + virtual ~Base() {} virtual void f() {} }; struct Derived : public Base { + virtual ~Derived() override {} virtual void f() override {} }; diff --git a/config/stdcxx.m4 b/config/stdcxx.m4 index 9e0a61e4d7..3948e376fd 100644 --- a/config/stdcxx.m4 +++ b/config/stdcxx.m4 @@ -150,7 +150,7 @@ AC_DEFUN([AX_CXX_COMPILE_STDCXX], [dnl else HAVE_CXX$1=1 AC_DEFINE(HAVE_CXX$1,1, - [define if the compiler supports basic C++$1 syntax]) + [Define if the compiler supports basic C++$1 syntax.]) fi AC_SUBST(HAVE_CXX$1) ])