Feature testing (C++20)

 

C++

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언어

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Feature test macros (C++20)

언어 지원 라이브러리

개념(C++20)

Diagnostics library

유틸리티 라이브러리

문자열 라이브러리

컨테이너 라이브러리

반복자 라이브러리

범위 라이브러리(C++20)

알고리즘 라이브러리

수치 라이브러리

지역화 라이브러리

입/출력 라이브러리

파일시스템 라이브러리(C++17)

정규 표현식 라이브러리(C++11)

아토믹 연산 라이브러리(C++11)

쓰레드 지원 라이브러리(C++11)

Technical specifications

Symbols index

외부 라이브러리들

 

Feature testing

 

The standard defines a set of preprocessor macros corresponding to C++ language and library features introduced in C++11 or later. They are intended as a simple and portable way to detect the presence of said features.

Attributes

__has_cpp_attribute(attribute-token)

Checks for the presence of an attribute named by attribute-token (after macro expansion).

For standard attributes, it will expand to the year and month in which the attribute was added to the working draft (see table below), the presence of vendor-specific attributes is determined by a non-zero value.

__has_cpp_attribute can be expanded in the expression of #if and #elif. It is treated as a defined macro by #ifdef, #ifndef and defined but cannot be used anywhere else.

attribute-token	Attribute	Value	Standard
carries_dependency	[[carries_dependency]]	200809L	(C++11)
deprecated	[[deprecated]]	201309L	(C++14)
fallthrough	[[fallthrough]]	201603L	(C++17)
likely	[[likely]]	201803L	(C++20)
maybe_unused	[[maybe_unused]]	201603L	(C++17)
no_unique_address	[[no_unique_address]]	201803L	(C++20)
nodiscard	[[nodiscard]]	201603L	(C++17)
		201907L	(C++20)
noreturn	[[noreturn]]	200809L	(C++11)
unlikely	[[unlikely]]	201803L	(C++20)

Language features

The following macros are predefined in every translation unit. Each macro expands to an integer literal corresponding to the year and month when the corresponding feature has been included in the working draft.

When a feature changes significantly, the macro will be updated accordingly.

Macro name	Feature	Value	Std
__cpp_aggregate_bases	Aggregate classes with base classes	201603L	(C++17)
__cpp_aggregate_nsdmi	Aggregate classes with default member initializers	201304L	(C++14)
__cpp_aggregate_paren_init	Aggregate initialization in the form of direct initialization	201902L	(C++20)
__cpp_alias_templates	Alias templates	200704L	(C++11)
__cpp_aligned_new	Dynamic memory allocation for over-aligned data	201606L	(C++17)
__cpp_attributes	Attributes	200809L	(C++11)
__cpp_binary_literals	Binary literals	201304L	(C++14)
__cpp_capture_star_this	Lambda capture of *this by value as [=,*this]	201603L	(C++17)
__cpp_char8_t	char8_t	201811L	(C++20)
__cpp_concepts	Concepts	201907L	(C++20)
__cpp_conditional_explicit	explicit(bool)	201806L	(C++20)
__cpp_consteval	Immediate functions	201811L	(C++20)
__cpp_constexpr	constexpr	200704L	(C++11)
	Relaxed constexpr, non-constconstexpr methods	201304L	(C++14)
	Constexpr lambda	201603L	(C++17)
	Trivial default initialization and asm-declaration in constexpr functions	201907L	(C++20)
	Non-literal variables, labels, and goto statements in constexpr functions	202110L	(C++23)
__cpp_constexpr_dynamic_alloc	Operations for dynamic storage duration in constexpr functions	201907L	(C++20)
__cpp_constexpr_in_decltype	Generation of function and variable definitions when needed for constant evaluation	201711L	(C++20)
__cpp_constinit	constinit	201907L	(C++20)
__cpp_decltype	decltype	200707L	(C++11)
__cpp_decltype_auto	Return type deduction for normal functions	201304L	(C++14)
__cpp_deduction_guides	Template argument deduction for class templates	201703L	(C++17)
	CTAD for aggregates and aliases	201907L	(C++20)
__cpp_delegating_constructors	Delegating constructors	200604L	(C++11)
__cpp_designated_initializers	Designated initializer	201707L	(C++20)
__cpp_enumerator_attributes	Attributes for enumerators	201411L	(C++17)
__cpp_explicit_this_parameter	Explicit object parameter	202110L	(C++23)
__cpp_fold_expressions	Fold expressions	201603L	(C++17)
__cpp_generic_lambdas	Generic lambda expressions	201304L	(C++14)
	Explicit template parameter list for generic lambdas	201707L	(C++20)
__cpp_guaranteed_copy_elision	Guaranteed copy elision through simplified value categories	201606L	(C++17)
__cpp_hex_float	Hexadecimal floating literals	201603L	(C++17)
__cpp_if_consteval	consteval if	202106L	(C++23)
__cpp_if_constexpr	constexpr if	201606L	(C++17)
__cpp_impl_coroutine	Coroutines (compiler support)	201902L	(C++20)
__cpp_impl_destroying_delete	Destroying operator delete (compiler support)	201806L	(C++20)
__cpp_impl_three_way_comparison	Three-way comparison (compiler support)	201907L	(C++20)
__cpp_inheriting_constructors	Inheriting constructors	200802L	(C++11)
	Rewording inheriting constructors	201511L	(C++17)
__cpp_init_captures	Lambda init-capture	201304L	(C++14)
	Allow pack expansion in lambda init-capture	201803L	(C++20)
__cpp_initializer_lists	List-initialization and std::initializer_list	200806L	(C++11)
__cpp_inline_variables	Inline variables	201606L	(C++17)
__cpp_lambdas	Lambda expressions	200907L	(C++11)
__cpp_modules	Modules	201907L	(C++20)
__cpp_multidimensional_subscript	Multidimensional subscript operator	202110L	(C++23)
__cpp_namespace_attributes	Attributes for namespaces	201411L	(C++17)
__cpp_noexcept_function_type	Make exception specifications be part of the type system	201510L	(C++17)
__cpp_nontype_template_args	Allow constant evaluation for all non-type template arguments	201411L	(C++17)
	Class types and floating-point types in non-type template parameters	201911L	(C++20)
__cpp_nontype_template_parameter_auto	Declaring non-type template parameters with auto	201606L	(C++17)
__cpp_nsdmi	Non-static data member initializers	200809L	(C++11)
__cpp_range_based_for	Range-based for loop	200907L	(C++11)
	Range-based for loop with different begin/end types	201603L	(C++17)
__cpp_raw_strings	Raw string literals	200710L	(C++11)
__cpp_ref_qualifiers	ref-qualifiers	200710L	(C++11)
__cpp_return_type_deduction	Return type deduction for normal functions	201304L	(C++14)
__cpp_rvalue_references	Rvalue reference	200610L	(C++11)
__cpp_size_t_suffix	Literal suffixes for size_t and its signed version	202011L	(C++23)
__cpp_sized_deallocation	Sized deallocation	201309L	(C++14)
__cpp_static_assert	static_assert	200410L	(C++11)
	Single-argument static_assert	201411L	(C++17)
__cpp_structured_bindings	Structured bindings	201606L	(C++17)
__cpp_template_template_args	Matching of template template-arguments	201611L	(C++17)
__cpp_threadsafe_static_init	Dynamic initialization and destruction with concurrency	200806L	(C++11)
__cpp_unicode_characters	New character types (char16_t and char32_t)	200704L	(C++11)
__cpp_unicode_literals	Unicode string literals	200710L	(C++11)
__cpp_user_defined_literals	User-defined literals	200809L	(C++11)
__cpp_using_enum	using enum	201907L	(C++20)
__cpp_variable_templates	Variable templates	201304L	(C++14)
__cpp_variadic_templates	Variadic templates	200704L	(C++11)
__cpp_variadic_using	Pack expansions in using-declarations	201611L	(C++17)

Library features

The following macros are defined if the header <version> or any of the corresponding headers in the table below is included. Each macro expands to an integer literal corresponding to the year and month when the corresponding feature has been included in the working draft.

When a feature changes significantly, the macro will be updated accordingly.

Macro name	Feature	Value	Header	Std
__cpp_lib_adaptor_iterator_pair_constructor	Iterator pair constructors for std::stack and std::queue	202106L	<stack><queue>	(C++23)
__cpp_lib_addressof_constexpr	Constexpr std::addressof	201603L	<memory>	(C++17)
__cpp_lib_allocate_at_least	std::allocate_at_least etc.	202106L	<memory>	(C++23)
__cpp_lib_allocator_traits_is_always_equal	std::allocator_traits::is_always_equal	201411L	<memory><scoped_allocator><string><deque><forward_list><list><vector><map><set><unordered_map><unordered_set>	(C++17)
__cpp_lib_any	std::any	201606L	<any>	(C++17)
__cpp_lib_apply	std::apply	201603L	<tuple>	(C++17)
__cpp_lib_array_constexpr	Constexpr for std::reverse_iterator, std::move_iterator, std::array and range access	201603L	<iterator><array>	(C++17)
	ConstexprIterator; constexpr comparison for std::array; misc constexpr bits (std::array::fill et al.)	201811L	<iterator><array>	(C++20)
__cpp_lib_as_const	std::as_const	201510L	<utility>	(C++17)
__cpp_lib_associative_heterogeneous_erasure	Heterogeneous erasure in associative containers and unordered associative containers	202110L	<map><set><unordered_map><unordered_set>	(C++23)
__cpp_lib_assume_aligned	std::assume_aligned	201811L	<memory>	(C++20)
__cpp_lib_atomic_flag_test	std::atomic_flag::test	201907L	<atomic>	(C++20)
__cpp_lib_atomic_float	Floating-point atomic	201711L	<atomic>	(C++20)
__cpp_lib_atomic_is_always_lock_free	constexpr atomic<T>::is_always_lock_free	201603L	<atomic>	(C++17)
__cpp_lib_atomic_lock_free_type_aliases	atomic lockfree integral types (std::atomic_signed_lock_free, std::atomic_unsigned_lock_free)	201907L	<atomic>	(C++20)
__cpp_lib_atomic_ref	std::atomic_ref	201806L	<atomic>	(C++20)
__cpp_lib_atomic_shared_ptr	std::atomic<std::shared_ptr>	201711L	<memory>	(C++20)
__cpp_lib_atomic_value_initialization	Fixing atomic initialization (value-initialize std::atomic by default)	201911L	<atomic><memory>	(C++20)
__cpp_lib_atomic_wait	Efficient std::atomic waiting	201907L	<atomic>	(C++20)
__cpp_lib_barrier	std::barrier	201907L	<barrier>	(C++20)
__cpp_lib_bind_front	std::bind_front	201907L	<functional>	(C++20)
__cpp_lib_bit_cast	std::bit_cast	201806L	<bit>	(C++20)
__cpp_lib_bitops	Bit operations	201907L	<bit>	(C++20)
__cpp_lib_bool_constant	std::bool_constant	201505L	<type_traits>	(C++17)
__cpp_lib_bounded_array_traits	std::is_bounded_array, std::is_unbounded_array	201902L	<type_traits>	(C++20)
__cpp_lib_boyer_moore_searcher	std::boyer_moore_searcher	201603L	<functional>	(C++17)
__cpp_lib_byte	std::byte	201603L	<cstddef>	(C++17)
__cpp_lib_byteswap	std::byteswap	202110L	<bit>	(C++23)
__cpp_lib_char8_t	Library support for char8_t	201907L	<atomic><filesystem><istream><limits><locale><ostream><string><string_view>	(C++20)
__cpp_lib_chrono	Rounding functions for std::chrono::duration and std::chrono::time_point	201510L	<chrono>	(C++17)
	Constexpr for all the member functions of std::chrono::duration and std::chrono::time_point	201611L	<chrono>	(C++17)
	Calendars and Time Zones	201907L	<chrono>	(C++20)
__cpp_lib_chrono_udls	User-defined literals for time types	201304L	<chrono>	(C++14)
__cpp_lib_clamp	std::clamp	201603L	<algorithm>	(C++17)
__cpp_lib_complex_udls	User-defined Literals for std::complex	201309L	<complex>	(C++14)
__cpp_lib_concepts	Standard library concepts	202002L	<concepts>	(C++20)
__cpp_lib_constexpr_algorithms	Constexpr for algorithms	201806L	<algorithm>	(C++20)
__cpp_lib_constexpr_complex	Constexpr for std::complex	201711L	<complex>	(C++20)
__cpp_lib_constexpr_dynamic_alloc	Constexpr for std::allocator and related utilities	201907L	<memory>	(C++20)
__cpp_lib_constexpr_functional	Misc constexpr bits (std::default_searcher); constexpr INVOKE	201907L	<functional>	(C++20)
__cpp_lib_constexpr_iterator	Misc constexpr bits (std::insert_iterator et al.)	201811L	<iterator>	(C++20)
__cpp_lib_constexpr_memory	Constexpr in std::pointer_traits	201811L	<memory>	(C++20)
__cpp_lib_constexpr_numeric	Constexpr for <numeric> algorithms	201911L	<numeric>	(C++20)
__cpp_lib_constexpr_string	Constexpr for std::string	201907L	<string>	(C++20)
__cpp_lib_constexpr_string_view	Misc constexpr bits (std::string_view::copy)	201811L	<string_view>	(C++20)
__cpp_lib_constexpr_tuple	Misc constexpr bits (std::tuple::operator= et al.)	201811L	<tuple>	(C++20)
__cpp_lib_constexpr_typeinfo	Constexpr for std::type_info::operator==	202106L	<typeinfo>	(C++23)
__cpp_lib_constexpr_utility	Misc constexpr bits (std::pair::operator= et al.)	201811L	<utility>	(C++20)
__cpp_lib_constexpr_vector	Constexpr for std::vector	201907L	<vector>	(C++20)
__cpp_lib_coroutine	Coroutines (library support)	201902L	<coroutine>	(C++20)
__cpp_lib_destroying_delete	Destroying operator delete (library support)	201806L	<new>	(C++20)
__cpp_lib_enable_shared_from_this	More precise specification of std::enable_shared_from_this	201603L	<memory>	(C++17)
__cpp_lib_endian	std::endian	201907L	<bit>	(C++20)
__cpp_lib_erase_if	Uniform container erasure	202002L	<string><deque><forward_list><list><vector><map><set><unordered_map><unordered_set>	(C++20)
__cpp_lib_exchange_function	std::exchange	201304L	<utility>	(C++14)
__cpp_lib_execution	Execution policies	201603L	<execution>	(C++17)
	std::execution::unsequenced_policy	201902L	<execution>	(C++20)
__cpp_lib_filesystem	Filesystem library	201703L	<filesystem>	(C++17)
__cpp_lib_format	Text formatting	201907L	<format>	(C++20)
	Compile-time format string checks; Reducing parameterization of std::vformat_to	202106L	<format>	(C++23)
	Fixing locale handling in chrono formatters; Use of forwarding references in format arguments	202110L	<format>	(C++23)
__cpp_lib_gcd_lcm	std::gcd, std::lcm	201606L	<numeric>	(C++17)
__cpp_lib_generic_associative_lookup	Heterogeneous comparison lookup in associative containers	201304L	<map><set>	(C++14)
__cpp_lib_generic_unordered_lookup	Heterogeneous comparison lookup in unordered associative containers	201811L	<unordered_map><unordered_set>	(C++20)
__cpp_lib_hardware_interference_size	constexpr std::hardware_{constructive, destructive}_interference_size	201703L	<new>	(C++17)
__cpp_lib_has_unique_object_representations	std::has_unique_object_representations	201606L	<type_traits>	(C++17)
__cpp_lib_hypot	3-argument overload of std::hypot	201603L	<cmath>	(C++17)
__cpp_lib_incomplete_container_elements	Minimal incomplete type support for standard containers	201505L	<forward_list><list><vector>	(C++17)
__cpp_lib_int_pow2	Integral power-of-2 operations (std::has_single_bit, std::bit_ceil, std::bit_floor, std::bit_length)	202002L	<bit>	(C++20)
__cpp_lib_integer_comparison_functions	Integer comparison functions	202002L	<utility>	(C++20)
__cpp_lib_integer_sequence	Compile-time integer sequences	201304L	<utility>	(C++14)
__cpp_lib_integral_constant_callable	std::integral_constant	201304L	<type_traits>	(C++14)
__cpp_lib_interpolate	std::lerp, std::midpoint	201902L	<cmath><numeric>	(C++20)
__cpp_lib_invoke	std::invoke	201411L	<functional>	(C++17)
__cpp_lib_invoke_r	std::invoke_r	202106L	<functional>	(C++23)
__cpp_lib_is_aggregate	std::is_aggregate	201703L	<type_traits>	(C++17)
__cpp_lib_is_constant_evaluated	std::is_constant_evaluated	201811L	<type_traits>	(C++20)
__cpp_lib_is_final	std::is_final	201402L	<type_traits>	(C++14)
__cpp_lib_is_invocable	std::is_invocable, std::invoke_result	201703L	<type_traits>	(C++17)
__cpp_lib_is_layout_compatible	std::is_layout_compatible	201907L	<type_traits>	(C++20)
__cpp_lib_is_nothrow_convertible	std::is_nothrow_convertible	201806L	<type_traits>	(C++20)
__cpp_lib_is_null_pointer	std::is_null_pointer	201309L	<type_traits>	(C++14)
__cpp_lib_is_pointer_interconvertible	Pointer-interconvertibility traits	201907L	<type_traits>	(C++20)
__cpp_lib_is_scoped_enum	std::is_scoped_enum	202011L	<type_traits>	(C++23)
__cpp_lib_is_swappable	[nothrow-]swappable traits	201603L	<type_traits>	(C++17)
__cpp_lib_jthread	Stop token and joining thread	201911L	<stop_token><thread>	(C++20)
__cpp_lib_latch	std::latch	201907L	<latch>	(C++20)
__cpp_lib_launder	Core Issue 1776: Replacement of class objects containing reference members (std::launder)	201606L	<new>	(C++17)
__cpp_lib_list_remove_return_type	Change the return type of the std::list::remove, std::list::remove_if and std::list::unique members of std::forward_list and std::list	201806L	<forward_list><list>	(C++20)
__cpp_lib_logical_traits	Logical operator type traits	201510L	<type_traits>	(C++17)
__cpp_lib_make_from_tuple	std::make_from_tuple()	201606L	<tuple>	(C++17)
__cpp_lib_make_reverse_iterator	std::make_reverse_iterator	201402L	<iterator>	(C++14)
__cpp_lib_make_unique	std::make_unique	201304L	<memory>	(C++14)
__cpp_lib_map_try_emplace	std::map::try_emplace, std::map::insert_or_assign	201411L	<map>	(C++17)
__cpp_lib_math_constants	Mathematical constants	201907L	<numbers>	(C++20)
__cpp_lib_math_special_functions	Mathematical special functions for C++17	201603L	<cmath>	(C++17)
__cpp_lib_memory_resource	std::pmr::memory_resource	201603L	<memory_resource>	(C++17)
__cpp_lib_monadic_optional	Monadic Operations in std::optional	202110L	<optional>	(C++23)
__cpp_lib_move_only_function	std::move_only_function	202110L	<functional>	(C++23)
__cpp_lib_node_extract	Splicing maps and sets (std::map::extract, std::map::merge, std::map::insert(node_type), etc)	201606L	<map><set><unordered_map><unordered_set>	(C++17)
__cpp_lib_nonmember_container_access	std::size(), std::data() and std::empty()	201411L	<iterator><array><deque><forward_list><list><map><regex><set><string><unordered_map><unordered_set><vector>	(C++17)
__cpp_lib_not_fn	std::not_fn()	201603L	<functional>	(C++17)
__cpp_lib_null_iterators	Null LegacyForwardIterators	201304L	<iterator>	(C++14)
__cpp_lib_optional	std::optional	201606L	<optional>	(C++17)
	Fully constexprstd::optional	202106L	<optional>	(C++23)
__cpp_lib_out_ptr	std::out_ptr, std::inout_ptr	202106L	<memory>	(C++23)
__cpp_lib_parallel_algorithm	Parallel algorithms	201603L	<algorithm><numeric>	(C++17)
__cpp_lib_polymorphic_allocator	std::pmr::polymorphic_allocator as a vocabulary type	201902L	<memory_resource>	(C++20)
__cpp_lib_quoted_string_io	std::quoted	201304L	<iomanip>	(C++14)
__cpp_lib_ranges	Ranges library and constrained algorithms	201911L	<algorithm><functional><iterator><memory><ranges>	(C++20)
	Non-default-initializableviews	202106L		(C++23)
	Views with ownership	202110L		(C++23)
__cpp_lib_ranges_starts_ends_with	std::ranges::starts_with, std::ranges::ends_with	202106L	<algorithm>	(C++23)
__cpp_lib_ranges_zip	std::ranges::zip_view, std::ranges::zip_transform_view, std::ranges::adjacent_view, std::ranges::adjacent_transform_view	202110L	<ranges><tuple><utility>	(C++23)
__cpp_lib_raw_memory_algorithms	Extending memory management tools	201606L	<memory>	(C++17)
__cpp_lib_remove_cvref	std::remove_cvref	201711L	<type_traits>	(C++20)
__cpp_lib_result_of_sfinae	std::result_of and SFINAE	201210L	<type_traits><functional>	(C++14)
__cpp_lib_robust_nonmodifying_seq_ops	Making non-modifying sequence operations more robust (two-range overloads for std::mismatch, std::equal and std::is_permutation)	201304L	<algorithm>	(C++14)
__cpp_lib_sample	std::sample	201603L	<algorithm>	(C++17)
__cpp_lib_scoped_lock	std::scoped_lock	201703L	<mutex>	(C++17)
__cpp_lib_semaphore	std::counting_semaphore, std::binary_semaphore	201907L	<semaphore>	(C++20)
__cpp_lib_shared_mutex	std::shared_mutex (untimed)	201505L	<shared_mutex>	(C++17)
__cpp_lib_shared_ptr_arrays	std::shared_ptr	201611L	<memory>	(C++17)
	Array support of std::make_shared	201707L	<memory>	(C++20)
__cpp_lib_shared_ptr_weak_type	shared_ptr::weak_type	201606L	<memory>	(C++17)
__cpp_lib_shared_timed_mutex	std::shared_timed_mutex	201402L	<shared_mutex>	(C++14)
__cpp_lib_shift	std::shift_left and std::shift_right	201806L	<algorithm>	(C++20)
__cpp_lib_smart_ptr_for_overwrite	Smart pointer creation with default initialization (std::allocate_shared_for_overwrite, std::make_shared_for_overwrite, std::make_unique_for_overwrite)	202002L	<memory>	(C++20)
__cpp_lib_source_location	Source-code information capture (std::source_location)	201907L	<source_location>	(C++20)
__cpp_lib_span	std::span	202002L	<span>	(C++20)
__cpp_lib_spanstream	std::spanbuf, std::spanstream	202106L	<spanstream>	(C++23)
__cpp_lib_ssize	std::ssize and unsigned std::span::size	201902L	<iterator>	(C++20)
__cpp_lib_stacktrace	Stacktrace library	202011L	<stacktrace>	(C++23)
__cpp_lib_starts_ends_with	String prefix and suffix checking (std::string_view::starts_with and std::string_view::ends_with for std::string and std::string_view)	201711L	<string><string_view>	(C++20)
__cpp_lib_stdatomic_h	Compatibility header for C atomic operations	202011L	<stdatomic.h>	(C++23)
__cpp_lib_string_contains	contains functions of std::basic_string and std::basic_string_view	202011L	<string><string_view>	(C++23)
__cpp_lib_string_resize_and_overwrite	std::basic_string::resize_and_overwrite	202110L	<string>	(C++23)
__cpp_lib_string_udls	User-defined literals for string types	201304L	<string>	(C++14)
__cpp_lib_string_view	std::string_view	201606L	<string><string_view>	(C++17)
	ConstexprIterator	201803L	<string><string_view>	(C++20)
__cpp_lib_syncbuf	Synchronized buffered ostream (std::syncbuf, std::osyncstream) and manipulators	201803L	<syncstream>	(C++20)
__cpp_lib_three_way_comparison	Three-way comparison (library support); adding three-way comparison to the library	201907L	<compare>	(C++20)
__cpp_lib_to_address	Utility to convert a pointer to a raw pointer (std::to_address)	201711L	<memory>	(C++20)
__cpp_lib_to_array	std::to_array	201907L	<array>	(C++20)
__cpp_lib_to_chars	Elementary string conversions (std::to_chars, std::from_chars)	201611L	<charconv>	(C++17)
__cpp_lib_to_underlying	std::to_underlying	202102L	<utility>	(C++23)
__cpp_lib_transformation_trait_aliases	Alias templates for TransformationTraits	201304L	<type_traits>	(C++14)
__cpp_lib_transparent_operators	Transparent operator functors (std::less<> et al)	201210L	<functional>	(C++14)
	Transparent std::owner_less (std::owner_less<void>)	201510L	<memory><functional>	(C++17)
__cpp_lib_tuple_element_t	std::tuple_element_t	201402L	<tuple>	(C++14)
__cpp_lib_tuples_by_type	Addressing tuples by type	201304L	<tuple><utility>	(C++14)
__cpp_lib_type_identity	std::type_identity	201806L	<type_traits>	(C++20)
__cpp_lib_type_trait_variable_templates	Type traits variable templates (std::is_void_v, etc)	201510L	<type_traits>	(C++17)
__cpp_lib_uncaught_exceptions	std::uncaught_exceptions	201411L	<exception>	(C++17)
__cpp_lib_unordered_map_try_emplace	std::unordered_map::try_emplace, std::unordered_map::insert_or_assign	201411L	<unordered_map>	(C++17)
__cpp_lib_unwrap_ref	std::unwrap_ref_decay and std::unwrap_reference	201811L	<type_traits>	(C++20)
__cpp_lib_variant	std::variant: a type-safe union for C++17	201606L	<variant>	(C++17)
	std::visit for classes derived from std::variant	202102L	<variant>	(C++23)
	Fully constexprstd::variant	202106L	<variant>	(C++23)
__cpp_lib_void_t	std::void_t	201411L	<type_traits>	(C++17)

Example

Normal usage

코드 실행

#ifdef __has_include // Check if __has_include is present# if __has_include(<optional>) // Check for a standard library# include <optional># elif __has_include(<experimental/optional>) // Check for an experimental version# include <experimental/optional># elif __has_include(<boost/optional.hpp>) // Try with an external library# include <boost/optional.hpp># else // Not found at all# error "Missing <optional>"# endif#endif   #ifdef __has_cpp_attribute // Check if __has_cpp_attribute is present# if __has_cpp_attribute(deprecated) // Check for an attribute# define DEPRECATED(msg) [[deprecated(msg)]]# endif#endif#ifndef DEPRECATED# define DEPRECATED(msg)#endif   DEPRECATED("foo() has been deprecated")void foo();   #if __cpp_constexpr >= 201304 // Check for a specific version of a feature# define CONSTEXPR constexpr#else# define CONSTEXPR inline#endif   CONSTEXPR int bar(unsigned i){#if __cpp_binary_literals // Check for the presence of a featureunsigned mask1 =0b11000000;unsigned mask2 =0b00000111;#elseunsigned mask1 =0xC0;unsigned mask2 =0x07;#endifif( i & mask1 )return1;if( i & mask2 )return2;return0;}   int main(){}

Compiler Features Dump

The following program dumps C++ compiler features and attributes.

코드 실행

#if __cplusplus < 201100# error "C++11 or better is required"#endif   #include <algorithm>#include <cstring>#include <iomanip>#include <iostream>#include <string>   #ifdef __has_include# if __has_include(<version>)# include <version># endif#endif   #define COMPILER_FEATURE_VALUE(value) #value#define COMPILER_FEATURE_ENTRY(name) { #name, COMPILER_FEATURE_VALUE(name) },   #ifdef __has_cpp_attribute# define COMPILER_ATTRIBUTE_VALUE_AS_STRING(s) #s# define COMPILER_ATTRIBUTE_AS_NUMBER(x) COMPILER_ATTRIBUTE_VALUE_AS_STRING(x)# define COMPILER_ATTRIBUTE_ENTRY(attr) \ { #attr, COMPILER_ATTRIBUTE_AS_NUMBER(__has_cpp_attribute(attr)) },#else# define COMPILER_ATTRIBUTE_ENTRY(attr) { #attr, "_" },#endif   // Change these options to print out only necessary info.staticstruct PrintOptions {constexprstaticbool titles =1;constexprstaticbool attributes =1;constexprstaticbool general_features =1;constexprstaticbool core_features =1;constexprstaticbool lib_features =1;constexprstaticbool supported_features =1;constexprstaticbool unsupported_features =1;constexprstaticbool sorted_by_value =0;constexprstaticbool cxx11 =1;constexprstaticbool cxx14 =1;constexprstaticbool cxx17 =1;constexprstaticbool cxx20 =1;constexprstaticbool cxx23 =1;} print;   struct CompilerFeature { CompilerFeature(constchar* name = nullptr, constchar* value = nullptr): name(name), value(value){}constchar* name;constchar* value;};   static CompilerFeature cxx[]={ COMPILER_FEATURE_ENTRY(__cplusplus) COMPILER_FEATURE_ENTRY(__cpp_exceptions) COMPILER_FEATURE_ENTRY(__cpp_rtti)#if 0 COMPILER_FEATURE_ENTRY(__GNUC__) COMPILER_FEATURE_ENTRY(__GNUC_MINOR__) COMPILER_FEATURE_ENTRY(__GNUC_PATCHLEVEL__) COMPILER_FEATURE_ENTRY(__GNUG__) COMPILER_FEATURE_ENTRY(__clang__) COMPILER_FEATURE_ENTRY(__clang_major__) COMPILER_FEATURE_ENTRY(__clang_minor__) COMPILER_FEATURE_ENTRY(__clang_patchlevel__)#endif};static CompilerFeature cxx11[]={ COMPILER_FEATURE_ENTRY(__cpp_alias_templates) COMPILER_FEATURE_ENTRY(__cpp_attributes) COMPILER_FEATURE_ENTRY(__cpp_constexpr) COMPILER_FEATURE_ENTRY(__cpp_decltype) COMPILER_FEATURE_ENTRY(__cpp_delegating_constructors) COMPILER_FEATURE_ENTRY(__cpp_inheriting_constructors) COMPILER_FEATURE_ENTRY(__cpp_initializer_lists) COMPILER_FEATURE_ENTRY(__cpp_lambdas) COMPILER_FEATURE_ENTRY(__cpp_nsdmi) COMPILER_FEATURE_ENTRY(__cpp_range_based_for) COMPILER_FEATURE_ENTRY(__cpp_raw_strings) COMPILER_FEATURE_ENTRY(__cpp_ref_qualifiers) COMPILER_FEATURE_ENTRY(__cpp_rvalue_references) COMPILER_FEATURE_ENTRY(__cpp_static_assert) COMPILER_FEATURE_ENTRY(__cpp_threadsafe_static_init) COMPILER_FEATURE_ENTRY(__cpp_unicode_characters) COMPILER_FEATURE_ENTRY(__cpp_unicode_literals) COMPILER_FEATURE_ENTRY(__cpp_user_defined_literals) COMPILER_FEATURE_ENTRY(__cpp_variadic_templates)};static CompilerFeature cxx14[]={ COMPILER_FEATURE_ENTRY(__cpp_aggregate_nsdmi) COMPILER_FEATURE_ENTRY(__cpp_binary_literals) COMPILER_FEATURE_ENTRY(__cpp_constexpr) COMPILER_FEATURE_ENTRY(__cpp_decltype_auto) COMPILER_FEATURE_ENTRY(__cpp_generic_lambdas) COMPILER_FEATURE_ENTRY(__cpp_init_captures) COMPILER_FEATURE_ENTRY(__cpp_return_type_deduction) COMPILER_FEATURE_ENTRY(__cpp_sized_deallocation) COMPILER_FEATURE_ENTRY(__cpp_variable_templates)};static CompilerFeature cxx14lib[]={ COMPILER_FEATURE_ENTRY(__cpp_lib_chrono_udls) COMPILER_FEATURE_ENTRY(__cpp_lib_complex_udls) COMPILER_FEATURE_ENTRY(__cpp_lib_exchange_function) COMPILER_FEATURE_ENTRY(__cpp_lib_generic_associative_lookup) COMPILER_FEATURE_ENTRY(__cpp_lib_integer_sequence) COMPILER_FEATURE_ENTRY(__cpp_lib_integral_constant_callable) COMPILER_FEATURE_ENTRY(__cpp_lib_is_final) COMPILER_FEATURE_ENTRY(__cpp_lib_is_null_pointer) COMPILER_FEATURE_ENTRY(__cpp_lib_make_reverse_iterator) COMPILER_FEATURE_ENTRY(__cpp_lib_make_unique) COMPILER_FEATURE_ENTRY(__cpp_lib_null_iterators) COMPILER_FEATURE_ENTRY(__cpp_lib_quoted_string_io) COMPILER_FEATURE_ENTRY(__cpp_lib_result_of_sfinae) COMPILER_FEATURE_ENTRY(__cpp_lib_robust_nonmodifying_seq_ops) COMPILER_FEATURE_ENTRY(__cpp_lib_shared_timed_mutex) COMPILER_FEATURE_ENTRY(__cpp_lib_string_udls) COMPILER_FEATURE_ENTRY(__cpp_lib_transformation_trait_aliases) COMPILER_FEATURE_ENTRY(__cpp_lib_transparent_operators) COMPILER_FEATURE_ENTRY(__cpp_lib_tuple_element_t) COMPILER_FEATURE_ENTRY(__cpp_lib_tuples_by_type)};   static CompilerFeature cxx17[]={ COMPILER_FEATURE_ENTRY(__cpp_aggregate_bases) COMPILER_FEATURE_ENTRY(__cpp_aligned_new) COMPILER_FEATURE_ENTRY(__cpp_capture_star_this) COMPILER_FEATURE_ENTRY(__cpp_constexpr) COMPILER_FEATURE_ENTRY(__cpp_deduction_guides) COMPILER_FEATURE_ENTRY(__cpp_enumerator_attributes) COMPILER_FEATURE_ENTRY(__cpp_fold_expressions) COMPILER_FEATURE_ENTRY(__cpp_guaranteed_copy_elision) COMPILER_FEATURE_ENTRY(__cpp_hex_float) COMPILER_FEATURE_ENTRY(__cpp_if_constexpr) COMPILER_FEATURE_ENTRY(__cpp_inheriting_constructors) COMPILER_FEATURE_ENTRY(__cpp_inline_variables) COMPILER_FEATURE_ENTRY(__cpp_namespace_attributes) COMPILER_FEATURE_ENTRY(__cpp_noexcept_function_type) COMPILER_FEATURE_ENTRY(__cpp_nontype_template_args) COMPILER_FEATURE_ENTRY(__cpp_nontype_template_parameter_auto) COMPILER_FEATURE_ENTRY(__cpp_range_based_for) COMPILER_FEATURE_ENTRY(__cpp_static_assert) COMPILER_FEATURE_ENTRY(__cpp_structured_bindings) COMPILER_FEATURE_ENTRY(__cpp_template_template_args) COMPILER_FEATURE_ENTRY(__cpp_variadic_using)};static CompilerFeature cxx17lib[]={ COMPILER_FEATURE_ENTRY(__cpp_lib_addressof_constexpr) COMPILER_FEATURE_ENTRY(__cpp_lib_allocator_traits_is_always_equal) COMPILER_FEATURE_ENTRY(__cpp_lib_any) COMPILER_FEATURE_ENTRY(__cpp_lib_apply) COMPILER_FEATURE_ENTRY(__cpp_lib_array_constexpr) COMPILER_FEATURE_ENTRY(__cpp_lib_as_const) COMPILER_FEATURE_ENTRY(__cpp_lib_atomic_is_always_lock_free) COMPILER_FEATURE_ENTRY(__cpp_lib_bool_constant) COMPILER_FEATURE_ENTRY(__cpp_lib_boyer_moore_searcher) COMPILER_FEATURE_ENTRY(__cpp_lib_byte) COMPILER_FEATURE_ENTRY(__cpp_lib_chrono) COMPILER_FEATURE_ENTRY(__cpp_lib_clamp) COMPILER_FEATURE_ENTRY(__cpp_lib_enable_shared_from_this) COMPILER_FEATURE_ENTRY(__cpp_lib_execution) COMPILER_FEATURE_ENTRY(__cpp_lib_filesystem) COMPILER_FEATURE_ENTRY(__cpp_lib_gcd_lcm) COMPILER_FEATURE_ENTRY(__cpp_lib_hardware_interference_size) COMPILER_FEATURE_ENTRY(__cpp_lib_has_unique_object_representations) COMPILER_FEATURE_ENTRY(__cpp_lib_hypot) COMPILER_FEATURE_ENTRY(__cpp_lib_incomplete_container_elements) COMPILER_FEATURE_ENTRY(__cpp_lib_invoke) COMPILER_FEATURE_ENTRY(__cpp_lib_is_aggregate) COMPILER_FEATURE_ENTRY(__cpp_lib_is_invocable) COMPILER_FEATURE_ENTRY(__cpp_lib_is_swappable) COMPILER_FEATURE_ENTRY(__cpp_lib_launder) COMPILER_FEATURE_ENTRY(__cpp_lib_logical_traits) COMPILER_FEATURE_ENTRY(__cpp_lib_make_from_tuple) COMPILER_FEATURE_ENTRY(__cpp_lib_map_try_emplace) COMPILER_FEATURE_ENTRY(__cpp_lib_math_special_functions) COMPILER_FEATURE_ENTRY(__cpp_lib_memory_resource) COMPILER_FEATURE_ENTRY(__cpp_lib_node_extract) COMPILER_FEATURE_ENTRY(__cpp_lib_nonmember_container_access) COMPILER_FEATURE_ENTRY(__cpp_lib_not_fn) COMPILER_FEATURE_ENTRY(__cpp_lib_optional) COMPILER_FEATURE_ENTRY(__cpp_lib_parallel_algorithm) COMPILER_FEATURE_ENTRY(__cpp_lib_raw_memory_algorithms) COMPILER_FEATURE_ENTRY(__cpp_lib_sample) COMPILER_FEATURE_ENTRY(__cpp_lib_scoped_lock) COMPILER_FEATURE_ENTRY(__cpp_lib_shared_mutex) COMPILER_FEATURE_ENTRY(__cpp_lib_shared_ptr_arrays) COMPILER_FEATURE_ENTRY(__cpp_lib_shared_ptr_weak_type) COMPILER_FEATURE_ENTRY(__cpp_lib_string_view) COMPILER_FEATURE_ENTRY(__cpp_lib_to_chars) COMPILER_FEATURE_ENTRY(__cpp_lib_transparent_operators) COMPILER_FEATURE_ENTRY(__cpp_lib_type_trait_variable_templates) COMPILER_FEATURE_ENTRY(__cpp_lib_uncaught_exceptions) COMPILER_FEATURE_ENTRY(__cpp_lib_unordered_map_try_emplace) COMPILER_FEATURE_ENTRY(__cpp_lib_variant) COMPILER_FEATURE_ENTRY(__cpp_lib_void_t)};   static CompilerFeature cxx20[]={ COMPILER_FEATURE_ENTRY(__cpp_aggregate_paren_init) COMPILER_FEATURE_ENTRY(__cpp_char8_t) COMPILER_FEATURE_ENTRY(__cpp_concepts) COMPILER_FEATURE_ENTRY(__cpp_conditional_explicit) COMPILER_FEATURE_ENTRY(__cpp_consteval) COMPILER_FEATURE_ENTRY(__cpp_constexpr) COMPILER_FEATURE_ENTRY(__cpp_constexpr_dynamic_alloc) COMPILER_FEATURE_ENTRY(__cpp_constexpr_in_decltype) COMPILER_FEATURE_ENTRY(__cpp_constinit) COMPILER_FEATURE_ENTRY(__cpp_deduction_guides) COMPILER_FEATURE_ENTRY(__cpp_designated_initializers) COMPILER_FEATURE_ENTRY(__cpp_generic_lambdas) COMPILER_FEATURE_ENTRY(__cpp_impl_coroutine) COMPILER_FEATURE_ENTRY(__cpp_impl_destroying_delete) COMPILER_FEATURE_ENTRY(__cpp_impl_three_way_comparison) COMPILER_FEATURE_ENTRY(__cpp_init_captures) COMPILER_FEATURE_ENTRY(__cpp_modules) COMPILER_FEATURE_ENTRY(__cpp_nontype_template_args) COMPILER_FEATURE_ENTRY(__cpp_using_enum)};static CompilerFeature cxx20lib[]={ COMPILER_FEATURE_ENTRY(__cpp_lib_array_constexpr) COMPILER_FEATURE_ENTRY(__cpp_lib_assume_aligned) COMPILER_FEATURE_ENTRY(__cpp_lib_atomic_flag_test) COMPILER_FEATURE_ENTRY(__cpp_lib_atomic_float) COMPILER_FEATURE_ENTRY(__cpp_lib_atomic_lock_free_type_aliases) COMPILER_FEATURE_ENTRY(__cpp_lib_atomic_ref) COMPILER_FEATURE_ENTRY(__cpp_lib_atomic_shared_ptr) COMPILER_FEATURE_ENTRY(__cpp_lib_atomic_value_initialization) COMPILER_FEATURE_ENTRY(__cpp_lib_atomic_wait) COMPILER_FEATURE_ENTRY(__cpp_lib_barrier) COMPILER_FEATURE_ENTRY(__cpp_lib_bind_front) COMPILER_FEATURE_ENTRY(__cpp_lib_bit_cast) COMPILER_FEATURE_ENTRY(__cpp_lib_bitops) COMPILER_FEATURE_ENTRY(__cpp_lib_bounded_array_traits) COMPILER_FEATURE_ENTRY(__cpp_lib_char8_t) COMPILER_FEATURE_ENTRY(__cpp_lib_chrono) COMPILER_FEATURE_ENTRY(__cpp_lib_concepts) COMPILER_FEATURE_ENTRY(__cpp_lib_constexpr_algorithms) COMPILER_FEATURE_ENTRY(__cpp_lib_constexpr_complex) COMPILER_FEATURE_ENTRY(__cpp_lib_constexpr_dynamic_alloc) COMPILER_FEATURE_ENTRY(__cpp_lib_constexpr_functional) COMPILER_FEATURE_ENTRY(__cpp_lib_constexpr_iterator) COMPILER_FEATURE_ENTRY(__cpp_lib_constexpr_memory) COMPILER_FEATURE_ENTRY(__cpp_lib_constexpr_numeric) COMPILER_FEATURE_ENTRY(__cpp_lib_constexpr_string) COMPILER_FEATURE_ENTRY(__cpp_lib_constexpr_string_view) COMPILER_FEATURE_ENTRY(__cpp_lib_constexpr_tuple) COMPILER_FEATURE_ENTRY(__cpp_lib_constexpr_utility) COMPILER_FEATURE_ENTRY(__cpp_lib_constexpr_vector) COMPILER_FEATURE_ENTRY(__cpp_lib_coroutine) COMPILER_FEATURE_ENTRY(__cpp_lib_destroying_delete) COMPILER_FEATURE_ENTRY(__cpp_lib_endian) COMPILER_FEATURE_ENTRY(__cpp_lib_erase_if) COMPILER_FEATURE_ENTRY(__cpp_lib_execution) COMPILER_FEATURE_ENTRY(__cpp_lib_format) COMPILER_FEATURE_ENTRY(__cpp_lib_generic_unordered_lookup) COMPILER_FEATURE_ENTRY(__cpp_lib_int_pow2) COMPILER_FEATURE_ENTRY(__cpp_lib_integer_comparison_functions) COMPILER_FEATURE_ENTRY(__cpp_lib_interpolate) COMPILER_FEATURE_ENTRY(__cpp_lib_is_constant_evaluated) COMPILER_FEATURE_ENTRY(__cpp_lib_is_layout_compatible) COMPILER_FEATURE_ENTRY(__cpp_lib_is_nothrow_convertible) COMPILER_FEATURE_ENTRY(__cpp_lib_is_pointer_interconvertible) COMPILER_FEATURE_ENTRY(__cpp_lib_jthread) COMPILER_FEATURE_ENTRY(__cpp_lib_latch) COMPILER_FEATURE_ENTRY(__cpp_lib_list_remove_return_type) COMPILER_FEATURE_ENTRY(__cpp_lib_math_constants) COMPILER_FEATURE_ENTRY(__cpp_lib_polymorphic_allocator) COMPILER_FEATURE_ENTRY(__cpp_lib_ranges) COMPILER_FEATURE_ENTRY(__cpp_lib_remove_cvref) COMPILER_FEATURE_ENTRY(__cpp_lib_semaphore) COMPILER_FEATURE_ENTRY(__cpp_lib_shared_ptr_arrays) COMPILER_FEATURE_ENTRY(__cpp_lib_shift) COMPILER_FEATURE_ENTRY(__cpp_lib_smart_ptr_for_overwrite) COMPILER_FEATURE_ENTRY(__cpp_lib_source_location) COMPILER_FEATURE_ENTRY(__cpp_lib_span) COMPILER_FEATURE_ENTRY(__cpp_lib_ssize) COMPILER_FEATURE_ENTRY(__cpp_lib_starts_ends_with) COMPILER_FEATURE_ENTRY(__cpp_lib_string_view) COMPILER_FEATURE_ENTRY(__cpp_lib_syncbuf) COMPILER_FEATURE_ENTRY(__cpp_lib_three_way_comparison) COMPILER_FEATURE_ENTRY(__cpp_lib_to_address) COMPILER_FEATURE_ENTRY(__cpp_lib_to_array) COMPILER_FEATURE_ENTRY(__cpp_lib_type_identity) COMPILER_FEATURE_ENTRY(__cpp_lib_unwrap_ref)};   static CompilerFeature cxx23[]={//< Continue to Populate COMPILER_FEATURE_ENTRY(__cpp_constexpr) COMPILER_FEATURE_ENTRY(__cpp_explicit_this_parameter) COMPILER_FEATURE_ENTRY(__cpp_if_consteval) COMPILER_FEATURE_ENTRY(__cpp_multidimensional_subscript) COMPILER_FEATURE_ENTRY(__cpp_size_t_suffix)};static CompilerFeature cxx23lib[]={//< Continue to Populate COMPILER_FEATURE_ENTRY(__cpp_lib_adaptor_iterator_pair_constructor) COMPILER_FEATURE_ENTRY(__cpp_lib_allocate_at_least) COMPILER_FEATURE_ENTRY(__cpp_lib_associative_heterogeneous_erasure) COMPILER_FEATURE_ENTRY(__cpp_lib_byteswap) COMPILER_FEATURE_ENTRY(__cpp_lib_constexpr_typeinfo) COMPILER_FEATURE_ENTRY(__cpp_lib_format) COMPILER_FEATURE_ENTRY(__cpp_lib_invoke_r) COMPILER_FEATURE_ENTRY(__cpp_lib_is_scoped_enum) COMPILER_FEATURE_ENTRY(__cpp_lib_monadic_optional) COMPILER_FEATURE_ENTRY(__cpp_lib_move_only_function) COMPILER_FEATURE_ENTRY(__cpp_lib_optional) COMPILER_FEATURE_ENTRY(__cpp_lib_out_ptr) COMPILER_FEATURE_ENTRY(__cpp_lib_ranges) COMPILER_FEATURE_ENTRY(__cpp_lib_ranges_starts_ends_with) COMPILER_FEATURE_ENTRY(__cpp_lib_ranges_zip) COMPILER_FEATURE_ENTRY(__cpp_lib_spanstream) COMPILER_FEATURE_ENTRY(__cpp_lib_stacktrace) COMPILER_FEATURE_ENTRY(__cpp_lib_stdatomic_h) COMPILER_FEATURE_ENTRY(__cpp_lib_string_contains) COMPILER_FEATURE_ENTRY(__cpp_lib_string_resize_and_overwrite) COMPILER_FEATURE_ENTRY(__cpp_lib_to_underlying) COMPILER_FEATURE_ENTRY(__cpp_lib_variant)};   static CompilerFeature attributes[]={ COMPILER_ATTRIBUTE_ENTRY(carries_dependency) COMPILER_ATTRIBUTE_ENTRY(deprecated) COMPILER_ATTRIBUTE_ENTRY(fallthrough) COMPILER_ATTRIBUTE_ENTRY(likely) COMPILER_ATTRIBUTE_ENTRY(maybe_unused) COMPILER_ATTRIBUTE_ENTRY(nodiscard) COMPILER_ATTRIBUTE_ENTRY(noreturn) COMPILER_ATTRIBUTE_ENTRY(no_unique_address) COMPILER_ATTRIBUTE_ENTRY(unlikely)};   constexprbool is_feature_supported(const CompilerFeature& x){return x.value[0]!='_'&& x.value[0]!='0';}   inlinevoid print_compiler_feature(const CompilerFeature& x){constexprstaticint max_name_length =44;//< Update if necessarystd::string value{ is_feature_supported(x)? x.value:"------"};if(value.back()=='L') value.pop_back();//~ 201603L -> 201603// value.insert(4, 1, '-'); //~ 201603 -> 2016-03if((print.supported_features&& is_feature_supported(x)) or (print.unsupported_features&&!is_feature_supported(x))){std::cout<<std::left<<std::setw(max_name_length)<< x.name<<" "<< value <<'\n';}}   template<size_t N>inlinevoid show(charconst* title, CompilerFeature (&features)[N]){if(print.titles){std::cout<<'\n'<<std::left<< title <<'\n';}if(print.sorted_by_value){std::sort(std::begin(features), std::end(features), [](CompilerFeature const& lhs, CompilerFeature const& rhs){returnstd::strcmp(lhs.value, rhs.value)<0;});}for(const CompilerFeature& x : features){ print_compiler_feature(x);}}   int main(){if(print.general_features) show("C++ GENERAL", cxx);if(print.cxx11&& print.core_features) show("C++11 CORE", cxx11);if(print.cxx14&& print.core_features) show("C++14 CORE", cxx14);if(print.cxx14&& print.lib_features) show("C++14 LIB" , cxx14lib);if(print.cxx17&& print.core_features) show("C++17 CORE", cxx17);if(print.cxx17&& print.lib_features) show("C++17 LIB" , cxx17lib);if(print.cxx20&& print.core_features) show("C++20 CORE", cxx20);if(print.cxx20&& print.lib_features) show("C++20 LIB" , cxx20lib);if(print.cxx23&& print.core_features) show("C++23 CORE", cxx23);if(print.cxx23&& print.lib_features) show("C++23 LIB" , cxx23lib);if(print.attributes) show("ATTRIBUTES", attributes);}

Possible output:

C++ GENERAL __cplusplus 202002 __cpp_exceptions 199711 __cpp_rtti 199711   C++11 CORE __cpp_alias_templates 200704 __cpp_attributes 200809 __cpp_constexpr 201907 __cpp_decltype 200707 __cpp_delegating_constructors 200604 __cpp_inheriting_constructors 201511 __cpp_initializer_lists 200806 __cpp_lambdas 200907 __cpp_nsdmi 200809 __cpp_range_based_for 201603 __cpp_raw_strings 200710 __cpp_ref_qualifiers 200710 __cpp_rvalue_references 200610 __cpp_static_assert 201411 __cpp_threadsafe_static_init 200806 __cpp_unicode_characters 200704 __cpp_unicode_literals 200710 __cpp_user_defined_literals 200809 __cpp_variadic_templates 200704   C++14 CORE __cpp_aggregate_nsdmi 201304 __cpp_binary_literals 201304 __cpp_constexpr 201907 __cpp_decltype_auto 201304 __cpp_generic_lambdas 201707 __cpp_init_captures 201803 __cpp_return_type_deduction 201304 __cpp_sized_deallocation ------ __cpp_variable_templates 201304   ... truncated ...

더 보기

Library feature-test macros(C++20)	defined in the header <version>
C++ documentation for Macro Symbol Index

외부 연결

The official document on Feature Test Recommendations

Source code to dump compiler features