#
# 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
# 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>
-# Copyright (c) 2016 Krzesimir Nowak <qdlacz@gmail.com>
+# Copyright (c) 2016, 2018 Krzesimir Nowak <qdlacz@gmail.com>
+# Copyright (c) 2019 Enji Cooper <yaneurabeya@gmail.com>
+# Copyright (c) 2020 Jason Merrill <jason@redhat.com>
+# Copyright (c) 2021 Jörn Heusipp <osmanx@problemloesungsmaschine.de>
#
# 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 8
+#serial 18
dnl This macro is based on the code from the AX_CXX_COMPILE_STDCXX_11 macro
dnl (serial version number 13).
m4_if([$1], [11], [ax_cxx_compile_alternatives="11 0x"],
[$1], [14], [ax_cxx_compile_alternatives="14 1y"],
[$1], [17], [ax_cxx_compile_alternatives="17 1z"],
+ [$1], [20], [ax_cxx_compile_alternatives="20"],
[m4_fatal([invalid first argument `$1' to AX_CXX_COMPILE_STDCXX])])dnl
m4_if([$2], [], [],
[$2], [ext], [],
AC_LANG_PUSH([C++])dnl
CXX_DIALECT=""
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], [], [dnl
+ 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
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"
+ dnl MSVC needs -std:c++NN for C++17 and later (default is C++14)
for alternative in ${ax_cxx_compile_alternatives}; do
- for switch in -std=c++${alternative} +std=c++${alternative} "-h std=c++${alternative}"; do
- cachevar=AS_TR_SH([ax_cv_cxx_compile_cxx$1_$switch])
+ for switch in -std=c++${alternative} +std=c++${alternative} "-h std=c++${alternative}" MSVC; do
+ if test x"$switch" = xMSVC; then
+ dnl AS_TR_SH maps both `:` and `=` to `_` so -std:c++17 would collide
+ dnl with -std=c++17. We suffix the cache variable name with _MSVC to
+ dnl avoid this.
+ switch=-std:c++${alternative}
+ cachevar=AS_TR_SH([ax_cv_cxx_compile_cxx$1_${switch}_MSVC])
+ else
+ cachevar=AS_TR_SH([ax_cv_cxx_compile_cxx$1_$switch])
+ fi
AC_CACHE_CHECK(whether $CXX supports C++$1 features with $switch,
$cachevar,
[ac_save_CXX="$CXX"
_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_14
)
+dnl Test body for checking C++17 support
+
m4_define([_AX_CXX_COMPILE_STDCXX_testbody_17],
_AX_CXX_COMPILE_STDCXX_testbody_new_in_11
_AX_CXX_COMPILE_STDCXX_testbody_new_in_14
_AX_CXX_COMPILE_STDCXX_testbody_new_in_17
)
+dnl Test body for checking C++20 support
+
+m4_define([_AX_CXX_COMPILE_STDCXX_testbody_20],
+ _AX_CXX_COMPILE_STDCXX_testbody_new_in_11
+ _AX_CXX_COMPILE_STDCXX_testbody_new_in_14
+ _AX_CXX_COMPILE_STDCXX_testbody_new_in_17
+ _AX_CXX_COMPILE_STDCXX_testbody_new_in_20
+)
+
+
dnl Tests for new features in C++11
m4_define([_AX_CXX_COMPILE_STDCXX_testbody_new_in_11], [[
#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"
struct Base
{
+ virtual ~Base() {}
virtual void f() {}
};
struct Derived : public Base
{
+ virtual ~Derived() override {}
virtual void f() override {}
};
#error "This is not a C++ compiler"
-#elif __cplusplus < 201402L
+#elif __cplusplus < 201402L && !defined _MSC_VER
#error "This is not a C++14 compiler"
#error "This is not a C++ compiler"
-#elif __cplusplus <= 201402L
+#elif __cplusplus < 201703L && !defined _MSC_VER
#error "This is not a C++17 compiler"
#else
-#if defined(__clang__)
- #define REALLY_CLANG
-#else
- #if defined(__GNUC__)
- #define REALLY_GCC
- #endif
-#endif
-
#include <initializer_list>
#include <utility>
#include <type_traits>
namespace cxx17
{
-#if !defined(REALLY_CLANG)
namespace test_constexpr_lambdas
{
- // TODO: test it with clang++ from git
-
constexpr int foo = [](){return 42;}();
}
-#endif // !defined(REALLY_CLANG)
namespace test::nested_namespace::definitions
{
}
-#if !defined(REALLY_CLANG)
namespace test_template_argument_deduction_for_class_templates
{
- // TODO: test it with clang++ from git
-
template <typename T1, typename T2>
struct pair
{
}
}
-#endif // !defined(REALLY_CLANG)
namespace test_non_type_auto_template_parameters
{
}
-#if !defined(REALLY_CLANG)
namespace test_structured_bindings
{
- // TODO: test it with clang++ from git
-
int arr[2] = { 1, 2 };
std::pair<int, int> pr = { 1, 2 };
const auto [ x3, y3 ] = f3();
}
-#endif // !defined(REALLY_CLANG)
-#if !defined(REALLY_CLANG)
namespace test_exception_spec_type_system
{
- // TODO: test it with clang++ from git
-
struct Good {};
struct Bad {};
static_assert (std::is_same_v<Good, decltype(f(g1, g2))>);
}
-#endif // !defined(REALLY_CLANG)
namespace test_inline_variables
{
} // namespace cxx17
-#endif // __cplusplus <= 201402L
+#endif // __cplusplus < 201703L && !defined _MSC_VER
+
+]])
+
+
+dnl Tests for new features in C++20
+
+m4_define([_AX_CXX_COMPILE_STDCXX_testbody_new_in_20], [[
+
+#ifndef __cplusplus
+
+#error "This is not a C++ compiler"
+
+#elif __cplusplus < 202002L && !defined _MSC_VER
+
+#error "This is not a C++20 compiler"
+
+#else
+
+#include <version>
+
+namespace cxx20
+{
+
+// As C++20 supports feature test macros in the standard, there is no
+// immediate need to actually test for feature availability on the
+// Autoconf side.
+
+} // namespace cxx20
+
+#endif // __cplusplus < 202002L && !defined _MSC_VER
]])
ac_compiler_gnu=$ac_cv_cxx_compiler_gnu
CXX_DIALECT=""
ac_success=no
- { $as_echo "$as_me:${as_lineno-$LINENO}: checking whether $CXX supports C++11 features by default" >&5
+
+ { $as_echo "$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
#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"
struct Base
{
+ virtual ~Base() {}
virtual void f() {}
};
struct Derived : public Base
{
+ virtual ~Derived() override {}
virtual void f() override {}
};
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$ax_cv_cxx_compile_cxx11 = xyes; then
- ac_success=yes
- fi
+ if test x$ax_cv_cxx_compile_cxx11 = xyes; then
+ ac_success=yes
+ fi
if test x$ac_success = xno; then
for alternative in ${ax_cxx_compile_alternatives}; do
#error "This is not a C++ compiler"
-#elif __cplusplus < 201103L
+// MSVC always sets __cplusplus to 199711L in older versions; newer versions
+// only set it correctly if /Zc:__cplusplus is specified as well as a
+// /std:c++NN switch:
+// https://devblogs.microsoft.com/cppblog/msvc-now-correctly-reports-__cplusplus/
+#elif __cplusplus < 201103L && !defined _MSC_VER
#error "This is not a C++11 compiler"
struct Base
{
+ virtual ~Base() {}
virtual void f() {}
};
struct Derived : public Base
{
+ virtual ~Derived() override {}
virtual void f() override {}
};
fi
if test x$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 :
#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"
struct Base
{
+ virtual ~Base() {}
virtual void f() {}
};
struct Derived : public Base
{
+ virtual ~Derived() override {}
virtual void f() override {}
};
ac_compiler_gnu=$ac_cv_cxx_compiler_gnu
CXX_DIALECT=""
ac_success=no
- { $as_echo "$as_me:${as_lineno-$LINENO}: checking whether $CXX supports C++11 features by default" >&5
+
+ { $as_echo "$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
#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"
struct Base
{
+ virtual ~Base() {}
virtual void f() {}
};
struct Derived : public Base
{
+ virtual ~Derived() override {}
virtual void f() override {}
};
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$ax_cv_cxx_compile_cxx11 = xyes; then
- ac_success=yes
- fi
+ if test x$ax_cv_cxx_compile_cxx11 = xyes; then
+ ac_success=yes
+ fi
if test x$ac_success = xno; then
for alternative in ${ax_cxx_compile_alternatives}; do
#error "This is not a C++ compiler"
-#elif __cplusplus < 201103L
+// MSVC always sets __cplusplus to 199711L in older versions; newer versions
+// only set it correctly if /Zc:__cplusplus is specified as well as a
+// /std:c++NN switch:
+// https://devblogs.microsoft.com/cppblog/msvc-now-correctly-reports-__cplusplus/
+#elif __cplusplus < 201103L && !defined _MSC_VER
#error "This is not a C++11 compiler"
struct Base
{
+ virtual ~Base() {}
virtual void f() {}
};
struct Derived : public Base
{
+ virtual ~Derived() override {}
virtual void f() override {}
};
fi
if test x$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 :
#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"
struct Base
{
+ virtual ~Base() {}
virtual void f() {}
};
struct Derived : public Base
{
+ virtual ~Derived() override {}
virtual void f() override {}
};
ac_compiler_gnu=$ac_cv_cxx_compiler_gnu
CXX_DIALECT=""
ac_success=no
- { $as_echo "$as_me:${as_lineno-$LINENO}: checking whether $CXX supports C++11 features by default" >&5
+
+ { $as_echo "$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
#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"
struct Base
{
+ virtual ~Base() {}
virtual void f() {}
};
struct Derived : public Base
{
+ virtual ~Derived() override {}
virtual void f() override {}
};
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$ax_cv_cxx_compile_cxx11 = xyes; then
- ac_success=yes
- fi
+ if test x$ax_cv_cxx_compile_cxx11 = xyes; then
+ ac_success=yes
+ fi
if test x$ac_success = xno; then
for alternative in ${ax_cxx_compile_alternatives}; do
#error "This is not a C++ compiler"
-#elif __cplusplus < 201103L
+// MSVC always sets __cplusplus to 199711L in older versions; newer versions
+// only set it correctly if /Zc:__cplusplus is specified as well as a
+// /std:c++NN switch:
+// https://devblogs.microsoft.com/cppblog/msvc-now-correctly-reports-__cplusplus/
+#elif __cplusplus < 201103L && !defined _MSC_VER
#error "This is not a C++11 compiler"
struct Base
{
+ virtual ~Base() {}
virtual void f() {}
};
struct Derived : public Base
{
+ virtual ~Derived() override {}
virtual void f() override {}
};
fi
if test x$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 :
#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"
struct Base
{
+ virtual ~Base() {}
virtual void f() {}
};
struct Derived : public Base
{
+ virtual ~Derived() override {}
virtual void f() override {}
};
projects / binutils-gdb.git / commitdiff