C++ compiler support

 

C++

Compiler support

Freestanding and hosted

Language

Standard library

Standard library headers

Named requirements

Feature test macros (C++20)

Language support library

Concepts library (C++20)

Diagnostics library

Memory management library

Metaprogramming library (C++11)

General utilities library

Containers library

Iterators library

Ranges library (C++20)

Algorithms library

Strings library

Text processing library

Numerics library

Date and time library

Input/output library

Filesystem library (C++17)

Concurrency support library (C++11)

Execution control library (C++26)

Technical specifications

Symbols index

External libraries

 

Compiler support

C++11

C++14

C++17

C++20

C++23

C++26

 

The following tables present compiler support for new C++ features. These include accepted revisions to the standard, as well as various technical specifications:

• C++26/2c core language features
• C++26/2c library features

• C++23 core language features
• C++23 library features

• C++20 core language features
• C++20 library features
• Older standards
• Vendor compatibility checklists

Notes

* - hover over a cell marked with the star * to see additional pop-up notes.
DRnn - the number nn after "DR" denotes target C++ revision the Defect Report is applied to, e.g., DR20 → C++20.

C++26 features

Note that this list may change, as the draft C++26/2c standard evolves.

C++26 core language features

C++26 feature	Paper(s)	GCC	Clang	MSVC	Apple Clang	EDG eccp	Intel C++	Nvidia HPC C++ (ex PGI)*	Nvidia nvcc	Cray
DR98: Removing undefined behavior from lexing	P2621R3	Yes	3.3		16.0.0*
DR98: Making non-encodable string literals ill-formed	P1854R4	14	14		16.0.0*
Unevaluated strings	P2361R6	14	17 (partial)* 18		16.0.0*
Adding @, $, and ` to the basic character set	P2558R2	15	Yes		16.0.0*
constexpr cast from void*  (FTM)*	P2738R1	14	17
DR20: On the ignorability of standard attributes	P2552R3	15	Yes
DR11: Static storage for braced initializers	P2752R3	14
User-generated static_assert messages  (FTM)*	P2741R3	14	17
Placeholder variables with no name  (FTM)*	P2169R4	14	18
Pack indexing  (FTM)*	P2662R3	15	19
Removing deprecated arithmetic conversion on enumerations	P2864R2	14	18
DR11/20: Template parameter initialization	P2308R1	9	18
Disallow binding a returned reference to a temporary	P2748R5	14	19
Attributes for structured bindings  (FTM)*	P0609R3	15	19
Erroneous behavior for uninitialized reads, [[indeterminate]] attribute	P2795R5
= delete("reason");  (FTM)*	P2573R2	15	19
Variadic friends  (FTM)*	P2893R3	15	20
DR98: Clarifying rules for brace elision in aggregate initialization	P3106R1	Yes	17
DR20: Disallow module declarations to be macros	P3034R1	15
DR11: Trivial infinite loops are not undefined behavior	P2809R3	14	19
constexpr placement new  (FTM)*  (FTM)*	P2747R2	15	20
Structured binding declaration as a condition  (FTM)*	P0963R3	15	6 (partial)* 21
Ordering of constraints involving fold expressions  (FTM)*	P2963R3		19
Deleting a pointer to an incomplete type should be ill-formed	P3144R2	15	19			6.7
Structured bindings can introduce a pack  (FTM)*	P1061R10		21
constexpr structured bindings and references to constexpr variables	P2686R5					6.7
constexpr exceptions: [1], [2]  (FTM)*	P3068R6
Oxford variadic comma	P3176R1	15	20
Removing deprecated array comparisons	P2865R6	15	20
#embed  (FTM)*	P1967R14	15	19*
Concept and variable-template template-parameters  (FTM)*	P2841R7
Trivial relocatability  (FTM)*	P2786R13
Trivial unions  (FTM)*	P3074R7
Observable checkpoints	P1494R5
Contracts  (FTM)*	P2900R14
C++26 feature	Paper(s)	GCC	Clang	MSVC	Apple Clang	EDG eccp	Intel C++	Nvidia HPC C++ (ex PGI)*	Nvidia nvcc	Cray

C++26 library features

C++26 feature	Paper(s)	GCC libstdc++	Clang libc++	MSVC STL	Apple Clang*
Testing for success or failure of <charconv> functions  (FTM)*	P2497R0	14	18		16.0.0*
std::text_encoding: text encodings identification  (FTM)*	P1885R12 P2862R1	14
Arithmetic overloads of std::to_string and std::to_wstring use std::format  (FTM)*	P2587R3	14
Type checking format args  (FTM)*	P2757R3	15
Formatting pointers  (FTM)*	P2510R3	14*	17*	19.40**
Hashing support for std::chrono value classes  (FTM)*	P2592R3
<rcu>: Read-Copy Update  (FTM)*	P2545R4
<hazard_pointer>: Hazard pointers  (FTM)*	P2530R3
ADL-proof std::projected	P2538R1	14*	18*	19.38**	16.0.0*
constexpr stable sorting  (FTM)*	P2562R1	15	21
Member std::basic_format_arg::visit()  (FTM)*	P2637R3	15	19
Member std::variant::visit()  (FTM)*	P2637R3	15	18
std::is_within_lifetime  (FTM)*	P2641R4
Extending associative containers with the remaining heterogeneous overloads  (FTM)*	P2363R5
Enabling the use of std::weak_ptr as keys in unordered associative containers  (FTM)*	P1901R2
Native handles in file streams  (FTM)*	P1759R6	14	18		16.0.0*
Interfacing string streams with std::string_view  (FTM)*	P2495R3		19
Interfacing std::bitset with std::string_view  (FTM)*	P2697R1		18		16.0.0*
More constexpr for <cmath> and <complex>  (FTM)*  (FTM)*	P1383R2	4.6 (partial)*
Adding the new 2022 SI prefixes on ratios: std::quecto, std::ronto, std::ronna, and std::quetta  (FTM)*	P2734R0	14	17*
std::function_ref: type-erased callable reference  (FTM)*	P0792R14
std::copyable_function  (FTM)*	P2548R6
std::bind_front, std::bind_back, and std::not_fn to NTTP callables  (FTM)*  (FTM)*  (FTM)*	P2714R1
std::submdspan()  (FTM)*	P2630R4 P3355R1
Freestanding language: Optional ::operator new	P2013R5			N/A
Freestanding std::char_traits, std::errc and facilities in: <charconv>, <cstdlib>, <cstring>, <cwchar>  (FTM)*  (FTM)*  (FTM)*  (FTM)*  (FTM)*  (FTM)*	P2338R4			N/A
More freestanding facilities  (FTM)*  (FTM)*  (FTM)*  (FTM)*  (FTM)*  (FTM)*  (FTM)*  (FTM)*	P2198R7			N/A
Saturation arithmetic  (FTM)*	P0543R3	14	18		16.0.0*
<debugging>: Debugging support  (FTM)*	P2546R5 P2810R4
<linalg>: A free function linear algebra interface based on the BLAS  (FTM)*	P1673R13 P3050R2 P3222R0
Making assert() macro user friendly	P2264R7
Runtime format strings  (FTM)*	P2918R2	14	18		16.0.0*
std::span over an initializer list  (FTM)*	P2447R6	15	18		16.0.0*
std::span::at()  (FTM)*	P2821R5	14	18		16.0.0*
Added tuple protocol to std::complex  (FTM)*	P2819R2	15	19
A new specification for std::generate_canonical	P0952R2			19.42*
Removing deprecated typedef std::allocator::is_always_equal	P2868R3	15	18		16.0.0*
Removing function overload of std::basic_string::reserve() that takes no argument	P2870R3		18		16.0.0*
Removing deprecated Unicode conversion facets (<codecvt>)	P2871R3		18		16.0.0*
Freestanding: removing std::strtok  (FTM)*	P2937R0	14		19.40*
Freestanding library: partial classes  (FTM)*  (FTM)*  (FTM)*  (FTM)*  (FTM)*	P2407R5	14		19.42*
Freestanding library: std::inout, std::expected, std::span  (FTM)*  (FTM)*  (FTM)*  (FTM)*	P2833R2	14		19.42*
DR23: std::basic_const_iterator should follow its underlying type’s convertibility  (FTM)*	P2836R1 P2950R0	14		19.40*
DR20: std::make_format_args now accepts only lvalue references instead of forwarding references	P2905R2	14	18	19.40*	16.0.0*
DR20: Fix formatting of code units as integers  (FTM)*	P2909R4	13.3	18	19.40*	16.0.0*
views::concat  (FTM)*	P2542R8	15
Concatenation of strings and string views  (FTM)*	P2591R5	15	19
Enabling list-initialization for algorithms  (FTM)*	P2248R8 P3217R0	15
std::ranges::generate_random  (FTM)*	P1068R11
Comparisons for std::reference_wrapper, and constraints for comparisons of std::pair, std::tuple, std::optional, and std::variant  (FTM)*  (FTM)*	P2944R3	14	19 (partial)*
Padded mdspan layouts  (FTM)*	P2642R6
New CTAD for std::span and std::mdspan with integral constants	P3029R1		19
Atomic maximum and minimum  (FTM)*	P0493R5
std::formatter<std::filesystem::path>  (FTM)*	P2845R8
Printing Blank Lines with std::println()  (FTM)*	P3142R0	14*	19*	19.41**
Undeprecate std::polymorphic_allocator::destroy	P2875R4		15	19.41*
Removing deprecated strstreams	P2867R2		19
Removing deprecated std::shared_ptr Atomic Access APIs	P2869R4
Removing std::wstring_convert	P2872R3		19
DR23: Permit an efficient implementation of std::print  (FTM)*	P3107R5 P3235R3			19.43*
Execution control library  (FTM)*	P2300R10 P3396R0
std::inplace_vector: dynamically-resizable vector with fixed capacity  (FTM)*	P0843R14
std::philox_engine: counter-based random number engine  (FTM)*	P2075R6
std::optional range support  (FTM)*	P3168R2
std::is_virtual_base_of: type trait for detecting virtual base classes  (FTM)*	P2985R0	15	20
std::dims for std::mdspan  (FTM)*	P2389R2		19
DR11: Formal specification of the type of std::ignore	P2968R2	15	19	19.42*
DR20: Removing the common reference requirement from the indirectly invocable concepts  (FTM)*	P2997R1	15	19	19.42*
Deprecating std::is_trivial and std::is_trivial_v	P3247R2	15	21
DR20: Algorithm function objects	P3136R1	Yes	14	19.39*	14.0.3*
std::ranges::cache_latest_view  (FTM)*	P3138R5	15
Constraining std::expected equality operators  (FTM)*	P3379R0	15
std::aligned_accessor: an std::mdspan accessor expressing pointer over-alignment  (FTM)*	P2897R7		21
std::is_sufficiently_aligned: checks a pointer’s alignment precondition  (FTM)*	P2897R7		21
std::atomic_ref::address()  (FTM)*	P2835R7
DR11/20: cv-qualified types in std::atomic and std::atomic_ref	P3323R1			19.44*
constexpr std::atomic and std::atomic_ref  (FTM)*	P3309R3
constexpr for specialized memory algorithms  (FTM)*	P3508R0 P3369R0	15
<stdbit.h> and <stdckdint.h>	P3370R1	15
<simd>: data-parallel types  (FTM)*  (FTM)*	P1928R15 P3430R3 P3441R2 P3287R3 P2663R7 P2933R4
A utility for creating execution environments	P3325R5
constexpr for exception types, e.g. std::bad_alloc, std::bad_cast etc.  (FTM)*	P3068R6 P3378R2
Trivial relocatability traits and operations  (FTM)*	P2786R13
Defang and deprecate std::memory_order::consume	P3475R1
Put std::monostate in <utility>	P0472R3	15	21	19.50*
std::indirect  (FTM)*	P3019R14
std::polymorphic  (FTM)*	P3019R14
More constexpr for containers and container adaptors: std::deque, std::flat_map, std::flat_multimap, std::flat_set, std::flat_multiset, std::forward_list, std::list, std::map, std::multimap, std::queue, std::priority_queue, std::set, std::multiset, std::stack, std::unordered_map, std::unordered_multimap, std::unordered_set, and std::unordered_multiset   (FTM)*  (FTM)*  (FTM)*  (FTM)*  (FTM)*  (FTM)*  (FTM)*  (FTM)*  (FTM)*  (FTM)*  (FTM)*	P3372R3
constexpr std::inplace_vector for non-trivial types  (FTM)*	P3074R7
std::ranges::to_input_view  (FTM)*	P3137R3	15
std::ranges::approximately_sized_range and std::ranges::reserve_hint  (FTM)*	P2846R6
<hive>: A bucket-based container that re-uses memory locations from erased elements  (FTM)*	P0447R28
<contracts>: Contract-violation handling support  (FTM)*	P2900R14
Standard library hardening  (FTM)*  (FTM)*  (FTM)*  (FTM)*  (FTM)*  (FTM)*  (FTM)*  (FTM)*  (FTM)*  (FTM)*  (FTM)*  (FTM)*  (FTM)*  (FTM)*	P3471R4	15 (partial)*		19.44* (partial)*
Freestanding library: <algorithm>, <numeric>, <random>, (<execution>, <memory>)   (FTM)*  (FTM)*  (FTM)*  (FTM)*  (FTM)*	P2976R1
DR20: Converting contiguous iterators to pointers	P3349R0	15
C++26 feature	Paper(s)	GCC libstdc++	Clang libc++	MSVC STL	Apple Clang*

C++23 features

C++23 core language features

C++23 feature	Paper(s)	GCC	Clang	MSVC	Apple Clang	EDG eccp	Intel C++	Nvidia HPC C++ (ex PGI)*	Nvidia nvcc	Cray
Literal suffix for (signed) size_t  (FTM)*	P0330R8	11	13	19.43*	13.1.6*	6.5	2022.2	23.9
Make () more optional for lambdas	P1102R2	11	13	19.44*	13.1.6*	6.3	2022.2	22.5
if consteval  (FTM)*	P1938R3	12	14	19.44*	14.0.0*	6.3	2022.2	24.1
Removing Garbage Collection Support	P2186R2	12	N/A	19.30*		N/A		N/A
Narrowing contextual conversions in static_assert and constexpr if	P1401R5	9	13 (partial)* 14		14.0.0*		2022.2	20.7
Trimming whitespaces before line splicing	P2223R2	Yes	Yes		Yes	6.7	2022.2	Yes
Make declaration order layout mandated	P1847R4	Yes	Yes	Yes	Yes		2022.2	Yes
Removing mixed wide string literal concatenation	P2201R1	Yes	Yes	Yes	Yes	Yes	Yes	Yes
Explicit object member functions (deducing this)  (FTM)*	P0847R7	14	18 19*	19.32* (partial)* 19.43*		6.3		22.5
auto(x) and auto{x}  (FTM)*	P0849R8	12	15		14.0.3*	6.4	2022.2	23.3
#elifdef and #elifndef	P2334R1	12	13	19.40*	13.1.6*	6.5	2022.2	23.9
Non-literal variables (and labels and gotos) in constexpr functions  (FTM)*	P2242R3	12	15	19.43*	14.0.3*	6.3	2022.2	22.5
Consistent character literal encoding	P2316R2	Yes	Yes	19.30*	Yes	Yes	2022.2	Yes
Character sets and encodings	P2314R4	10	Yes		Yes	Yes	2022.2	Yes
Extend init-statement (of for loop) to allow alias-declaration	P2360R0	12	14		14.0.0*		2022.2
Multidimensional subscript operator  (FTM)*	P2128R6	12	15	19.42*	14.0.3*		2022.2
Attributes on lambdas	P2173R1	9	13	19.44*	13.1.6*	6.6	2022.2	22.5
#warning	P2437R1	Yes*	Yes		15.0.0*	6.5	2023.2	Yes
Remove non-encodable wide character literals and multicharacter wide character literals	P2362R3	13	14		15.0.0*	6.7	2023.2
Labels at the end of compound statements	P2324R2	13	16		16.0.0*	6.5	2023.2	23.9
Delimited escape sequences	P2290R3	13	15		15.0.0*	6.7	2023.2
Named universal character escapes  (FTM)*	P2071R2	13	15		15.0.0*	6.7	2023.2
Relaxing some constexpr restrictions  (FTM)*	P2448R2	13	17 (partial) 19				2024.0 (partial)
Simpler implicit move  (FTM)*	P2266R3	13	13			6.7	2022.2
static operator()  (FTM)*	P1169R4	13	16	19.44*	16.0.0*	6.7	2023.2
Requirements for optional extended floating-point types	P1467R9	13		N/A		6.4
Class template argument deduction from inherited constructors	P2582R1	14
Attribute [[assume]]	P1774R8	13	19
Support for UTF-8 as a portable source file encoding	P2295R6	13*	15*	19.0 (Update 2)**	15.0.0*		2023.2
static operator[]  (FTM)*	P2589R1	13	16	19.44*	16.0.0*	6.7	2023.2
Permitting static constexpr variables in constexpr functions  (FTM)*	P2647R1	13	16		16.0.0*		2023.2
Extending the lifetime of temporaries in range-based for loop initializer  (FTM)*	P2644R1 P2718R0 CWG2659	15	19
DR11: Change scope of lambda trailing-return-type	P2036R3 P2579R0		17				2023.2
DR20: Meaningful exports	P2615R1	15	17 (partial)
DR20: consteval needs to propagate up  (FTM)*	P2564R3	14	17		16.0.0*	6.7	2024.0
DR98: C++ Identifier Syntax using Unicode Standard Annex 31	P1949R7	12	14		14.0.0*	6.4	2022.2
DR11: Allow duplicate attributes	P2156R1	11	13		13.1.6*	6.5		23.9
DR20: Adjusting the value of feature-test macro __cpp_concepts	P2493R0	12		19.32*		6.4		23.3
DR98: Relax requirements on wchar_t to match existing practices	P2460R2	Yes	Yes	Yes	15.0.0*	N/A	2023.2
DR11: Using unknown pointers and references in constant expressions	P2280R4	14	20*
DR20: The Equality Operator You Are Looking For	P2468R2	13	16		16.0.0*		2023.2
DR20: char8_t Compatibility and Portability Fix  (FTM)*	P2513R4	13	16	19.34*	16.0.0*		2023.2
DR98/11: Clarify reporting of diagnostic directives and allow static_assert of non-value-dependent expressions in a template context	CWG2518	13	17	16.0* (partial)* 19.40*
C++23 feature	Paper(s)	GCC	Clang	MSVC	Apple Clang	EDG eccp	Intel C++	Nvidia HPC C++ (ex PGI)*	Nvidia nvcc	Cray

C++23 library features

C++23 feature	Paper(s)	GCC libstdc++	Clang libc++	MSVC STL	Apple Clang*
Stacktrace library  (FTM)*	P0881R7 P2301R1	12 (partial)* 14*		19.34*
<stdatomic.h>  (FTM)*	P0943R6	12	15	19.31*	14.0.3*
std::is_scoped_enum  (FTM)*	P1048R1	11	12	19.30*	13.0.0*
std::basic_string::contains(), std::basic_string_view::contains()  (FTM)*	P1679R3	11	12	19.30*	13.0.0*
std::to_underlying  (FTM)*	P1682R3	11	13	19.30*	13.1.6*
Relaxing requirements for time_point<>::clock	P2212R2	N/A	N/A	N/A	N/A
Providing size feedback in the Allocator interface  (FTM)*	P0401R6		15	19.30*	14.0.3*
<spanstream>: string-stream with std::span-based buffer  (FTM)*	P0448R4	12		19.31*
std::out_ptr(), std::inout_ptr()  (FTM)*	P1132R8	14	19	19.30*
constexpr type_info::operator==()  (FTM)*	P1328R1	12	17	19.33** 19.34*	15.0.0*
Iterator pair constructors for std::stack and std::queue  (FTM)*	P1425R4	12	14	19.31*	14.0.3*
Non-deduction context for allocators in container deduction guides	P1518R2	12*	13*	19.31**	13.1.6**
ranges::starts_with() and ranges::ends_with()  (FTM)*	P1659R3		17 (partial)* 18	19.31*	16.0.0*
Prohibiting std::basic_string and std::basic_string_view construction from nullptr	P2166R1	12	13	19.30*	13.1.6*
std::invoke_r()  (FTM)*	P2136R3	12	17	19.31*	15.0.0*
Range constructor for std::basic_string_view	P1989R2	11	14	19.30*	14.0.3*
Default template arguments for std::pair's forwarding constructor	P1951R1	14	14	19.30*	14.0.3*
Remove Garbage Collection and Reachability-Based Detection (library support)	P2186R2	12	14	19.30*	14.0.3*
zip: views::zip, views::zip_transform, views::adjacent, and views::adjacent_transform  (FTM)*	P2321R2	13	15 (partial)*	19.33*(partial)*** 19.37*	14.0.3*
Heterogeneous erasure overloads for associative containers  (FTM)*	P2077R3			19.32*
std::byteswap()  (FTM)*	P1272R4	12	14	19.31*	14.0.3*
Printing volatile T*	P1147R1	11.3	14	19.31*	14.0.3*
basic_string::resize_and_overwrite()  (FTM)*	P1072R10	12	14	19.31*	14.0.3*
Monadic operations for std::optional  (FTM)*	P0798R8	12	14	19.32*	14.0.3*
std::move_only_function  (FTM)*	P0288R9	12		19.32*
Add a conditional noexcept specification to std::exchange	P2401R0	12	14	19.25*	14.0.3*
Require std::span & std::basic_string_view to be TriviallyCopyable	P2251R1	Yes	Yes	Yes	Yes
Clarifying the status of the “C headers”	P2340R1	Yes	Yes	Yes	Yes
<expected>  (FTM)*	P0323R12 P2549R1	12	16	19.33*	15.0.0*
constexpr for <cmath> and <cstdlib>  (FTM)*	P0533R9	4.6 (partial)*
std::unreachable()  (FTM)*	P0627R6	12	15	19.32*	14.0.3*
Deprecating std::aligned_storage and std::aligned_union	P1413R3	13	16	19.33*
std::reference_constructs_from_temporary & std::reference_converts_from_temporary  (FTM)*	P2255R2	13 (partial)* 14	21 (partial)*
constexpr std::unique_ptr  (FTM)*	P2273R3	12	16	19.33*	15.0.0*
Constructing containers and strings from ranges with ranges::to(), tagged constructors, insert and assign member functions  (FTM)*  (FTM)*	P1206R7	14 (partial)* 15	17	19.34*	15.0.0*
Pipe support for user-defined range adaptors (ranges::range_adaptor_closure, std::bind_back)  (FTM)*  (FTM)*	P2387R3	13 (partial)* 14	19	19.34*
ranges::iota(), ranges::shift_left(), and ranges::shift_right()  (FTM)*  (FTM)*	P2440R1	13 (partial)*		19.34*
views::join_with  (FTM)*	P2441R2	13		19.34*
views::chunk and views::slide  (FTM)*  (FTM)*	P2442R1	13		19.33*
views::chunk_by  (FTM)*	P2443R1	13	18	19.33*	16.0.0*
std::mdspan: a non-owning multidimensional array reference  (FTM)*	P0009R18 P2599R2 P2604R0 P2613R1 P2763R1		17 (partial)* 18	19.39*	15.0.0*
<flat_map>  (FTM)*	P0429R9	15	20
<flat_set>  (FTM)*	P1222R4	15	21
ranges::find_last(), ranges::find_last_if(), and ranges::find_last_if_not()  (FTM)*	P1223R5	13	19	19.36*
Freestanding Library: Easy <utility>, <ranges>, and <iterator>	P1642R11	13*		N/A
views::stride  (FTM)*	P1899R3	13		19.34*
Compatibility between std::tuple and tuple-like objects  (FTM)*	P2165R4	14	2.9 (partial)*	19.36* (partial)* 19.37*	partial*
Rectifying constant iterators, sentinels, and ranges. views::as_const  (FTM)*	P2278R4	13		19.35* (partial)* 19.36*
Formatting Ranges  (FTM)*	P2286R8	15 (partial)* 15.2	16	19.37*(partial)* 19.39*(partial)* 19.41*(partial)* 19.42*	15.0.0*
Improve default container formatting  (FTM)*	P2585R1	15	16 (partial)* 17	19.42*	15.0.0*
Formatted output library <print>  (FTM)*	P2093R14 P2539R4	14	17 (partial)* 18	19.37*	15.0.0** 16.0.0*
Formatting std::thread::id and std::stacktrace  (FTM)*	P2693R1	14	17 (partial)*	19.38*	15.0.0*
constexpr for integral overloads of std::to_chars() and std::from_chars()  (FTM)*	P2291R3	13	16	19.34*	15.0.0*
ranges::contains() and ranges::contains_subrange()  (FTM)*	P2302R4	13	18 (partial)* 19	19.34*	16.0.0**
Ranges fold algorithms  (FTM)*	P2322R6	13		19.35*
views::cartesian_product  (FTM)*	P2374R4 P2540R1	13		19.37*
Adding move-only types support for comparison concepts (equality_comparable, totally_ordered, three_way_comparable)  (FTM)*	P2404R3			19.36*
Ranges iterators as inputs to non-ranges algorithms  (FTM)*	P2408R5			19.34*
constexpr std::bitset  (FTM)*	P2417R2	13	16	19.34*	15.0.0*
basic_string::substr() &&	P2438R2		16	19.34*	15.0.0*
views::as_rvalue  (FTM)*	P2446R2	13	16	19.34*	15.0.0*
Standard Library Modules  (FTM)*	P2465R3	15*	17 (partial)*	19.35* (partial)* 19.36*
std::forward_like()  (FTM)*	P2445R1	14	16	19.34*	15.0.0*
Support exclusive mode for std::fstream  (FTM)*	P2467R1	12	18	19.36*	16.0.0*
views::repeat  (FTM)*	P2474R2	13	17	19.36*	15.0.0*
Relaxing range adaptors to allow for move-only types  (FTM)*	P2494R2	14	17	19.34*	15.0.0*
std::basic_string_view range constructor should be explicit	P2499R0	12.2	16	19.34*	15.0.0*
std::generator: synchronous coroutine generator for ranges  (FTM)*	P2502R2 P2787R0	14		19.43*
Add a conditional noexcept specification to std::apply	P2517R1	10	18	19.34*	16.0.0*
Explicit lifetime management (std::start_lifetime_as)  (FTM)*	P2590R2 P2679R2
Clarify handling of encodings in localized formatting of chrono types  (FTM)*	P2419R2	15*		19.34**
std::move_iterator should not always be input_iterator  (FTM)*	P2520R0	12.3*	17*	19.34**	15.0.0*
Deduction guides update for explicit object parameter call operators	LWG3617	14		19.34*
Deduction guides update for static operator()	P1169R4	13	16	19.39*	15.0.0*
Standard names and library support for extended floating-point types	P1467R9	13		19.37**
Monadic operations for std::expected  (FTM)*	P2505R5	13	17	19.36*	15.0.0*
views::enumerate  (FTM)*	P2164R9	13		19.37*
std::is_implicit_lifetime  (FTM)*	P2674R1		20
std::common_reference_t of std::reference_wrapper should be a reference type  (FTM)*  (FTM)*	P2655R3			19.37*
Disallowing user specialization of std::allocator_traits	P2652R2		19	19.37*
Deprecating std::numeric_limits::has_denorm	P2614R2		18	19.37*	16.0.0*
Making Multi-Param Constructors Of views explicit	P2711R1		17 (partial)*	19.36**	15.0.0*
DR20: Relaxing Ranges Just A Smidge  (FTM)*	P2609R3	15	20	19.37*
DR20: Stashing Stashing Iterators For Proper Flattening	P2770R0	14	18	19.37*
DR17: std::visit() for classes derived from std::variant  (FTM)*	P2162R2	11.3	13	19.20** 19.30*	13.1.6*
DR20: Conditionally borrowed ranges	P2017R1	11	16	19.30*
DR20: Repairing input range adaptors and std::counted_iterator	P2259R1	12		19.30*(partial)* 19.31*
DR20: views::join should join all views of ranges	P2328R1	11.2	15	19.30*	14.0.3*
DR20: view does not require default_initializable  (FTM)*	P2325R3	11.3	16	19.30*	15.0.0*
DR20: Range adaptor objects bind arguments by value	P2281R1	11	14	19.29 (16.10)* (partial)* 19.31*	14.0.3*
DR20: constexpr for std::optional and std::variant  (FTM)*  (FTM)*	P2231R1	11.3 (partial)* 12	13 (partial)* 19	19.31*	13.1.6* (partial)
DR20: views::lazy_split and redesigned views::split	P2210R2	12	16	19.31*	15.0.0*
DR20: Fix ranges::istream_view	P2432R1	12	16	19.31*	15.0.0*
DR20: view with ownership  (FTM)*	P2415R2	12	14	19.31*	14.0.3*
DR20: Fixing locale handling in chrono formatters  (FTM)*	P2372R3 P2418R2	13		19.31*
DR20: Cleaning up integer-class types	P2393R1			19.32*
DR20: Compile-time format string checks; Reducing binary code size of std::format() family  (FTM)*	P2216R3	13	14 (partial)* 15	19.32*	14.0.3*
DR20: Add support for non-const-formattable types to std::format	P2418R2	13	15	19.32*	14.0.3*
DR20: std::basic_format_string	P2508R1	13	15	19.35*	14.0.3*
DR20: Poison Pills are Too Toxic  (FTM)*	P2602R2	14	19	19.36*
DR20: std::format fill character allowances	P2572R1	14	17	19.37*
DR20: Improving std::format's width estimation	P2675R1	14	17	19.38*
DR20: std::barrier's phase completion guarantees  (FTM)*	P2588R3			19.28 (16.8)** 19.36*
C++23 feature	Paper(s)	GCC libstdc++	Clang libc++	MSVC STL	Apple Clang*

C++20 features

C++20 core language features

C++20 feature	Paper(s)	GCC	Clang	MSVC	Apple Clang	EDG eccp	Intel C++	Nvidia HPC C++ (ex PGI)*	Nvidia nvcc	Cray
Allow Lambda capture [=, this]	P0409R2	8	6	19.22*	10.0.0*	5.1	2021.1	20.7	12.0	11.0
__VA_OPT__	P0306R4 P1042R1	8 (partial)* 10 (partial)* 12	9	19.25*	11.0.3*	5.1	2021.1	20.7	12.0	11.0
Designated initializers  (FTM)*	P0329R4	4.7 (partial)* 8	3.0 (partial)* 10	19.21*	12.0.0*	5.1	2021.1	20.7	12.0	11.0
template-parameter-list for generic lambdas  (FTM)*	P0428R2	8	9	19.22*	11.0.0*	5.1	2021.1	20.7	12.0	11.0
Default member initializers for bit-fields	P0683R1	8	6	19.25*	10.0.0*	5.1	2021.1	20.7	12.0	11.0
Initializer list constructors in class template argument deduction	P0702R1	8	6	19.14*	Yes	5.0	2021.1	20.7	12.0	11.0
const&-qualified pointers to members	P0704R1	8	6	19.0 (2015)*	10.0.0*	5.1	2021.1	20.7	12.0	11.0
Concepts  (FTM)*	P0734R0	5* 10	10	19.23* (partial)* 19.30*	12.0.0* (partial)	6.1	2023.1*	20.11	12.0	11.0
Lambdas in unevaluated contexts	P0315R4	9	13 (partial)* 14 (partial)* 17	19.28 (16.8)*	13.1.6* (partial)	6.2	2023.1 (partial) 2024.0	20.7	12.0
Three-way comparison operator  (FTM)*	P0515R3	10	8 (partial) 10	19.20*	12.0.0*	5.1	2021.1	20.7	12.0	11.0
DR11: Simplifying implicit lambda capture	P0588R1	8		19.24*		5.1	2021.1	20.7	12.0
init-statements for range-based for	P0614R1	9	8	19.25*	11.0.0*	6.0	2021.7	20.11	12.0	11.0
Default constructible and assignable stateless lambdas	P0624R2	9	8	19.22*	10.0.1*	5.1	2021.1	20.7	12.0	11.0
Type mismatch of defaulted special member functions	P0641R2	9 (partial)*	8	19.0 (2015)* (partial)*	10.0.1*	5.1	2021.1	20.7	12.0	11.0
Access checking on specializations	P0692R1	Yes	8 (partial) 14	19.26*	14.0.0*	5.1	2021.1	20.7	12.0
ADL and function templates that are not visible	P0846R0	9	9	19.21*	11.0.3*	5.1	2021.1	20.7	12.0	11.0
DR11: Specify when constexpr function definitions are needed for constant evaluation  (FTM)*	P0859R0	5.2 (partial)* 9	8	19.27* (partial)* 19.31**	11.0.0*	(partial)			12.0	11.0
Attributes [[likely]] and [[unlikely]]	P0479R5	9	12	19.26*	13.0.0*	5.1	2021.7	20.7	12.0
Make typename more optional	P0634R3	9	16	19.29 (16.10)*	16.0.0*	5.1	2023.1	20.7	12.0
Pack-expansions in lambda init-captures  (FTM)*	P0780R2	9	9	19.22*	11.0.3*	6.1	2021.7	20.11	12.0	11.0
Attribute [[no_unique_address]]	P0840R2	9	9	19.28 (16.9)**	11.0.3*	5.1	2021.1	20.7	12.0	11.0
Conditionally trivial special member functions  (FTM)*	P0848R3	10	16	19.28 (16.8)*		6.1	2021.7	20.11	12.0
DR17: Relaxing the structured bindings customization point finding rules	P0961R1	8	8	19.20*	10.0.1*	5.1	2021.1	20.7	12.0	11.0
DR11: Relaxing the range-for loop customization point finding rules	P0962R1	8	8	19.25*	11.0.0*	5.1	2021.1	20.7	12.0	11.0
DR17: Allow structured bindings to accessible members	P0969R0	8	8	19.20*	10.0.1*	5.1	2021.1	20.7	12.0	11.0
Destroying operator delete  (FTM)*	P0722R3	9	6	19.27*	10.0.0*	6.1	2023.1	20.11	12.0	11.0
Class types in Constant template parameters	P0732R2	9	12 (partial)	19.26*(partial)* 19.28 (16.9)*	13.0.0* (partial)	6.2	2023.1 (partial)	21.3	12.0
Deprecate implicit capture of this via [=]	P0806R2	9	7	19.22*	10.0.1*	5.1		20.7	12.0	11.0
explicit(bool)  (FTM)*	P0892R2	9	9	19.24*	11.0.3*	5.1	2021.1	20.7	12.0	11.0
Integrating feature-test macros	P0941R2	5	3.4	19.15* (partial) 19.20*	Yes	5.0	2021.1	20.7	12.0	11.0
Prohibit aggregates with user-declared constructors	P1008R1	9	8	19.20*	10.0.1*	5.1	2021.1	20.7	12.0	11.0
constexpr virtual function  (FTM)*	P1064R0	9	9	19.28 (16.9)*	11.0.3*	5.1	2021.1	20.7	12.0	11.0
Consistency improvements for comparisons	P1120R0	10	8 (partial) 10	19.22*	12.0.0*	5.1	2023.1	20.7	12.0	11.0
char8_t  (FTM)*	P0482R6	9	7*	19.22*	10.0.0*	5.1	2021.1	20.7	12.0	11.0
std::is_constant_evaluated()  (FTM)*	P0595R2	9	9	19.25*	11.0.3*	5.1	19.1	21.1	12.0	11.0
constexpr try-catch blocks	P1002R1	9	8	19.25*	10.0.1*	5.1	2023.1	20.7	12.0	11.0
Immediate functions (consteval)  (FTM)*	P1073R3	10 (partial)* 11	11 (partial) 14 (partial)* 17	19.28 (16.8)* (partial)* 19.29 (16.10)*	11.0.3* (partial) 15.0.0*	5.1	2021.1	20.7	12.0
Nested inline namespaces	P1094R2	9	8	19.27*	10.0.1*	5.1	2021.1	20.7	12.0	11.0
Yet another approach for constrained declarations	P1141R2	10	10	19.26* (partial) 19.28 (16.9)*	12.0.5*	6.1	2023.1	20.11	12.0	11.0
Signed integers are two's complement	P1236R1	9	9	Yes	11.0.3*	N/A	2023.1*	yes*	12.0	11.0
dynamic_cast and polymorphic typeid in constant expressions	P1327R1	10	9	19.28 (16.9)*	11.0.3*	5.1	2021.1	20.7	12.0	11.0
Changing the active member of a union inside constexpr  (FTM)*	P1330R0	9	9	19.10*	11.0.3*	5.1	2021.1	20.7	12.0	11.0
Coroutines  (FTM)*  (FTM)*	P0912R5 LWG3393	10	8 (partial) 17 (partial)*	19.0 (2015)* (partial) 19.10** 19.28 (16.8)*	10.0.1* (partial)	5.1	2021.1	23.3*	12.0 (host code only)
Parenthesized initialization of aggregates  (FTM)*	P0960R3	10	16	19.28 (16.8)*	16.0.0*	5.1	2021.1	20.7	12.0
DR11: Array size deduction in new-expressions	P1009R2	11	9	19.27*	11.0.3*	5.1	2021.1	20.7	12.0	11.0
Modules  (FTM)*	P1103R3	11 (partial)	8 (partial)	19.0 (2015)* (partial) 19.10** 19.28 (16.8)*	10.0.1* (partial)		2023.1 (partial)
Stronger Unicode requirements	P1041R4 P1139R2	10	Yes	19.0 (2015)** 19.26**	Yes	N/A	2023.1*	Yes	12.0	11.0
<=> != ==	P1185R2	10	10	19.22*	12.0.0*	5.1	2021.1	20.7	12.0	11.0
DR11: Explicitly defaulted functions with different exception specifications	P1286R2	10	9	19.28 (16.8)*	11.0.3*	5.1	2021.1	20.7	12.0	11.0
Lambda capture and storage class specifiers of structured bindings	P1091R3 P1381R1	10	8 (partial) 16	19.11** 19.24**	16.0.0*	5.1	2021.1	20.7	12.0
Permit conversions to arrays of unknown bound	P0388R4	10	14	19.27*	14.0.0*	6.0	2021.5	20.11	12.0
constexpr container operations  (FTM)*	P0784R7	10	10	19.28 (16.9)*	12.0.0*	6.0	2021.5	20.11	12.0	11.0
Deprecating some uses of volatile	P1152R4	10	10	19.27*	12.0.0*	6.0	2021.5	20.11	12.0	11.0
constinit  (FTM)*	P1143R2	10	10	19.29 (16.10)*	12.0.0*	6.1	2021.7	20.11	12.0	11.0
Deprecate comma operator in subscripts	P1161R3	10	9	19.25*	11.0.3*	6.0	2021.7	20.11	12.0	11.0
[[nodiscard]] with message	P1301R4	10	9	19.25*	11.0.3*	6.0	2021.5	20.11	12.0	11.0
Trivial default initialization in constexpr functions	P1331R2	10	10	19.27*	12.0.0*	6.1	2021.7	20.11	12.0	11.0
Unevaluated asm-declaration in constexpr functions	P1668R1	10	10	19.28 (16.9)*	12.0.0*	6.1	2021.7	20.11	12.0	11.0
using enum  (FTM)*	P1099R5	11	13	19.24*	13.1.6*	6.3	2023.1	22.5	12.0
Synthesizing Three-way comparison for specified comparison category	P1186R3	11	10	19.24*	12.0.0*	6.0	2021.5	20.11	12.0	11.0
DR17: [[nodiscard]] for constructors	P1771R1	10	9	19.24*	11.0.3*	6.0	2021.5	20.11	12.0	11.0
class template argument deduction for alias templates  (FTM)*	P1814R0	10	19	19.27*		6.5		23.9	12.0
class template argument deduction for aggregates  (FTM)*	P1816R0 P2082R1	10* 11*	17	19.27*		6.3	2023.1 (partial)* 2024.1	23.3	12.0
DR11: Implicit move for more local objects and rvalue references	P1825R0	11*	13	19.24*	13.1.6*	6.0	2021.5	20.11	12.0
Allow defaulting comparisons by value	P1946R0	10	10	19.25*	12.0.0*	6.1	2021.7	20.11	12.0	11.0
Remove std::weak_equality and std::strong_equality	P1959R0	10	10	19.25*	12.0.0*	6.1	2021.7	20.11	12.0	11.0
Inconsistencies with constant template parameters  (FTM)*	P1907R1	10 (partial) 11	18 (partial)*	19.26*	13.1.6* (partial)	6.2	2023.1 (partial)	21.3	12.0
DR98: Pseudo-destructors end object lifetimes	P0593R6	11	11	Yes	12.0.5*	N/A	2023.1*	Yes	12.0	11.0
DR11: Converting from T* to bool should be considered narrowing	P1957R2	10* 11*	11	19.27*	12.0.5*	6.1			12.0	11.0
C++20 feature	Paper(s)	GCC	Clang	MSVC	Apple Clang	EDG eccp	Intel C++	Nvidia HPC C++ (ex PGI)*	Nvidia nvcc	Cray

C++20 library features

C++20 feature	Paper(s)	GCC libstdc++	Clang libc++	MSVC STL	Apple Clang*
std::endian  (FTM)*	P0463R1	8	7	19.22*	10.0.0*
Extending std::make_shared() to support arrays  (FTM)*	P0674R1	12	15	19.27*	14.0.3*
Floating-point atomic  (FTM)*	P0020R6	10	18	19.22*	16.0.0*
Synchronized buffered (std::basic_osyncstream)  (FTM)*	P0053R7	11	18	19.29 (16.10)*
constexpr for <algorithm> and <utility>  (FTM)*	P0202R3	10	8 (partial) 12	19.26*	10.0.1* (partial) 13.0.0*
More constexpr for <complex>  (FTM)*	P0415R1	9	7 (partial) 16	19.27*	10.0.0* (partial) 15.0.0*
Make std::memory_order a scoped enumeration	P0439R0	9	9	19.25*	11.0.3*
String prefix and suffix checking: string(_view) ::starts_with / ends_with  (FTM)*	P0457R2	9	6	19.21*	10.0.0*
Library support for operator<=> <compare>  (FTM)*	P0768R1	10	7 (partial) 12 (partial)* 17	19.20* (partial) 19.28 (16.9)*	13.0.0*
std::remove_cvref  (FTM)*	P0550R2	9	6	19.20*	10.0.0*
[[nodiscard]] in the standard library	P0600R1	9	7 (partial) 16	19.13* (partial) 19.22*	10.0.0* (partial) 15.0.0*
Using std::move in numeric algorithms	P0616R0	9	12	19.23*	13.0.0*
Utility to convert a pointer to a raw pointer  (FTM)*	P0653R2	8	6	19.22*	Yes
Atomic std::shared_ptr and std::weak_ptr  (FTM)*	P0718R2	12		19.27*
std::span  (FTM)*	P0122R7	10	7	19.26*	10.0.0*
Calendar and Time zone  (FTM)*	P0355R7	11 (partial)* 13 (partial)* 14	7 (partial) 19 (partial)*	19.29 (16.10)*	10.0.0* (partial)
<version>	P0754R2	9	7	19.22*	10.0.0*
Comparing unordered containers	P0809R0	Yes	Yes	16.0*	Yes
ConstexprIterator requirements  (FTM)*  (FTM)*	P0858R0	9	12	19.11*	13.0.0*
std::basic_string::reserve() should not shrink	P0966R1	11	8	19.25*	10.0.1*
Atomic Compare-And-Exchange with padding bits	P0528R3	13		19.28 (16.8)*
std::atomic_ref  (FTM)*	P0019R8	10	19	19.28 (16.8)*
contains() member function of associative containers, e.g. std::map::contains()	P0458R2	9	13	19.21*	13.1.6*
DR11: Guaranteed copy elision for piecewise construction	P0475R1	9	Yes	19.29 (16.10)*	Yes
std::bit_cast()  (FTM)*	P0476R2	11	14	19.27*	14.0.3*
Integral power-of-2 operations: std::bit_ceil(), std::bit_floor(), std::bit_width(), std::has_single_bit()  (FTM)*	P0556R3 P1956R1	9* 10*	9* 12*	19.25** 19.27** 19.28 (16.8)*	11.0.3** 13.0.0**
Improving the return value of erase-like algorithms  (FTM)*	P0646R1	9	10	19.21*	12.0.0*
std::destroying_delete_t  (FTM)*	P0722R3	9	9	19.27*	11.0.3*
std::is_convertible  (FTM)*	P0758R1	9	9	19.23*	11.0.3*
Add std::shift_left/right to <algorithm>  (FTM)*	P0769R2	10	12	19.21*	13.0.0*
Constexpr for std::swap() and swap related functions	P0879R0	10	13	19.26*	13.1.6*
std::type_identity  (FTM)*	P0887R1	9	8	19.21*	10.0.1*
Concepts library  (FTM)*	P0898R3	10	13	19.23*	13.1.6*
constexpr comparison operators for std::array	P1023R0	10	8	19.27*	10.0.1*
std::unwrap_ref_decay and std::unwrap_reference  (FTM)*	P0318R1	9	8	19.21*	10.0.1*
std::bind_front()  (FTM)*	P0356R5	9	13	19.25*	13.1.6*
std::reference_wrapper for incomplete types	P0357R3	9	8	19.26*	10.0.1*
Fixing operator>>(basic_istream&, CharT*)	P0487R1	11	8	19.23*	10.0.1*
Library support for char8_t  (FTM)*	P0482R6	9	8 (partial) 16	19.22*	10.0.1* (partial) 15.0.0*
Utility functions to implement uses-allocator construction	P0591R4	9	16	19.29 (16.10)*	15.0.0*
DR17: std::variant and std::optional should propagate copy/move triviality	P0602R4	8.3	8	19.11*	10.0.1*
DR17: A sane std::variant converting constructor	P0608R3	10	9	19.29 (16.10)** 19.42**	11.0.3*
std::function's move constructor should be noexcept	P0771R1	7.2	6	19.22*	Yes
The One Ranges Proposal  (FTM)*	P0896R4	10	13 (partial) 15*	19.29 (16.10)*	14.0.3*
Heterogeneous lookup for unordered associative containers  (FTM)*	P0919R3 P1690R1	11	12	19.23* (P0919R3) 19.25* (P1690R1)	13.0.0*
<chrono> zero(), min(), and max() should be noexcept	P0972R0	9	8	19.14*	10.0.1*
constexpr in std::pointer_traits  (FTM)*	P1006R1	9	8	19.26*	10.0.1*
std::assume_aligned()  (FTM)*	P1007R3	9* 11	15	19.28 (16.9)*	14.0.3*
Smart pointer creation with default initialization (e.g. make_unique_for_overwrite)  (FTM)*	P1020R1 P1973R1	11* 12*	16	19.28 (16.9)*	15.0.0*
Misc constexpr bits  (FTM)*  (FTM)*  (FTM)*  (FTM)*  (FTM)*  (FTM)*	P1032R1	10	13	19.28 (16.8)*	13.1.6*
Remove comparison operators of std::span	P1085R2	10	8	19.26*	10.0.1*
Make stateful allocator propagation more consistent for operator+(basic_string)	P1165R1	10	15	19.26*	14.0.3*
Consistent container erasure, e.g. std::erase(std::vector), or std::erase_if(std::map)  (FTM)*	P1209R0 P1115R3	9* 10*	8* 11*	19.25** 19.27**	10.0.1** 12.0.5**
Standard library header units	P1502R1	11		19.29 (16.10)*
polymorphic_allocator<> as a vocabulary type  (FTM)*	P0339R6	9	16	19.28 (16.9)*	15.0.0*
std::execution::unseq  (FTM)*	P1001R2	9	17	19.28 (16.8)*
std::lerp() and std::midpoint()  (FTM)*	P0811R3	9	9	19.23* (partial) 19.28 (16.8)*	11.0.3*
Usability enhancements for std::span	P1024R3	10	9* 14	19.26*	11.0.3*
DR17: Make std::create_directory() intuitive	P1164R1	8.3	12	19.20*	13.0.0*
std::ssize() and unsigned extent for std::span  (FTM)*	P1227R2	10	9	19.25*	11.0.3*
Traits for (un)bounded arrays  (FTM)*	P1357R1	9	9	19.25*	11.0.3*
std::to_array()  (FTM)*	P0325R4	10	10	19.25*	12.0.0*
Efficient access to std::basic_stringbuf’s buffer	P0408R7	11	17	19.29 (16.10)*	15.0.0*
Layout-compatibility and pointer-interconvertibility traits  (FTM)*  (FTM)*	P0466R5	12		19.29 (16.10)**
Bit operations: std:: rotl(), rotr(), countl_zero(), countl_one(), countr_zero(), countr_one(), popcount()  (FTM)*	P0553R4	9	9	19.25** 19.28 (16.8)*	11.0.3*
Mathematical constants  (FTM)*	P0631R8	10	11	19.25*	12.0.5*
Text formatting  (FTM)*	P0645R10	13	14** 17	19.29 (16.10)*	15.0.0*
std::stop_token and std::jthread  (FTM)*	P0660R10	10	17 (partial)* 20*	19.28 (16.9)*
constexpr std::allocator and related utilities  (FTM)*	P0784R7	10	12	19.29 (16.10)*	13.0.0*
constexpr std::string  (FTM)*	P0426R1 P1032R1 P0980R1	12	15	19.29 (16.10)* 19.30**	14.0.3*
constexpr std::vector  (FTM)*	P1004R2	12	15	19.29 (16.10)* 19.30**	14.0.3*
Input range adaptors	P1035R7	10	16	19.29 (16.10)*	15.0.0*
constexpr std::invoke() and related utilities	P1065R2	10	12	19.28 (16.8)*	13.0.0*
Atomic waiting and notifying, std::counting_semaphore, std::latch and std::barrier  (FTM)*  (FTM)*  (FTM)*  (FTM)*  (FTM)*  (FTM)*	P1135R6	11	11	19.28 (16.9)*	13.1.6*
std::source_location  (FTM)*	P1208R6	11	15* (partial) 16	19.29 (16.10)*	15.0.0*
Adding <=> to the standard library	P1614R2	10	14* (partial) 17* (partial) 19	19.29 (16.10)*	13.1.6* (partial)
constexpr default constructor of std::atomic and std::atomic_flag  (FTM)*	P0883R2	10	13	19.26*	13.1.6*
constexpr for numeric algorithms  (FTM)*	P1645R1	10	12	19.26*	13.0.0*
Safe integral comparisons  (FTM)*	P0586R2	10	13	19.27*	13.1.6*
C++20 feature	Paper(s)	GCC libstdc++	Clang libc++	MSVC STL	Apple Clang*

Older standards

• C++17 core language features
• C++17 library features

• C++14 core language features
• C++14 library features

• C++11 core language features
• C++11 library features

See also

Feature testing (C++20)	A set of preprocessor macros to test the corresponding to C++ language and library features
C documentation for compiler support