C++26

 

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

 

Versions

C++98

C++03

C++11

C++14

C++17

C++20

C++23

C++26

Current status

 

The next generation of the C++ standard.

The current IS schedule for C++26: P1000R6 (2024-05-14).

New library features

New headers

• <contracts>
• <debugging>
• <hazard_pointer>
• <hive>
• <inplace_vector>
• <linalg>
• <meta>
• <rcu>
• <simd>
• <text_encoding>

C compatibility headers:

• <stdbit.h>
• <stdchkint.h>

Compiler support

Main Article: C++26 compiler support

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 P3684R1	16
= 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	16	21
constexpr structured bindings and references to constexpr variables	P2686R5	16*				6.7
constexpr exceptions  (FTM)*	P3068R6	16
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 unions  (FTM)*	P3074R7 P3726R2
Observable checkpoints	P1494R5	16
Contracts  (FTM)*	P2900R14	16
Reflection  (FTM)*	P2996R13 P3394R4 P3293R3 P3096R12 P3795R2	16*
Expansion statements  (FTM)*	P1306R5	16
constexpr virtual inheritance  (FTM)*	P3533R2	16
Diagnosing Preprocessor Errors	P2843R3	16
Allowing attaching main to the global module	P3618R0	16
DR20: Allowing #line before module declarations	P3868R1
DR17: Class template argument deduction for type template template parameters	P3865R3
Const-ification of splice expressions in contract assertions	P3598R0
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	16
<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 P3450R1
Extending associative containers with the remaining heterogeneous overloads  (FTM)*	P2363R5	16
Enabling the use of std::weak_ptr as keys in unordered associative containers  (FTM)*	P1901R2	16
Native handles in file streams  (FTM)*	P1759R6	14	18		16.0.0*
Interfacing string streams with std::string_view  (FTM)*	P2495R3	16	19
Interfacing std::bitset with std::string_view  (FTM)*	P2697R1	16	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 P3961R1	16
std::copyable_function  (FTM)*	P2548R6	16
std::bind_front, std::bind_back, and std::not_fn to NTTP callables  (FTM)*  (FTM)*  (FTM)*	P2714R1	16
std::submdspan()  (FTM)*	P2630R4 P3355R1 P3663R3 P3982R2	16
Freestanding Language: Optional ::operator new	P2013R5			19.38*
Freestanding std::char_traits, std::errc and facilities in: <charconv>, <cstdlib>, <cstring>, <cwchar>  (FTM)*  (FTM)*  (FTM)*  (FTM)*  (FTM)*  (FTM)*	P2338R4			19.38*
More freestanding facilities  (FTM)*  (FTM)*  (FTM)*  (FTM)*  (FTM)*  (FTM)*  (FTM)*  (FTM)*	P2198R7			19.38*
Saturation Arithmetic  (FTM)*	P0543R3 P4052R0	14 16*	18		16.0.0*
<debugging>: Debugging support  (FTM)*	P2546R5 P2810R4	16*
<linalg>: A free function linear algebra interface based on the BLAS  (FTM)*	P1673R13 P3050R2 P3222R0 P3371R5
Making assert() macro user friendly	P2264R7	Yes*
Dynamic format strings  (FTM)*	P2918R2 P3953R3	14* 16*	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	16		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 P3787R2	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	16
New CTAD for std::span and std::mdspan with integral constants	P3029R1	16	19
Atomic maximum and minimum  (FTM)*	P0493R5	16
std::formatter<std::filesystem::path>  (FTM)*	P2845R8	16
Printing Blank Lines with std::println()  (FTM)*	P3142R0	14*	19*	19.41**
Undeprecate std::polymorphic_allocator::destroy	P2875R4	14.3*	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	16		19.43*
Execution control library  (FTM)*	P2300R10 P3396R0 P3570R2 P3481R5 P3433R1 P3682R0 P3388R3 P3887R1
Additional execution control library fixes	P3826R5 P4159R0 P4154R0 P3373R4 P3986R1
std::inplace_vector: dynamically-resizable vector with fixed capacity  (FTM)*	P0843R14 P3981R2 P4022R0	16
std::philox_engine: counter-based random number engine  (FTM)*	P2075R6	16
std::optional range support  (FTM)*	P3168R2 P3913R1	16
std::is_virtual_base_of: type trait for detecting virtual base classes  (FTM)*	P2985R0	15	20
std::dims for std::mdspan  (FTM)*	P2389R2	16	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	Yes	19.39*	Yes
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	16
std::is_sufficiently_aligned: checks a pointer’s alignment precondition  (FTM)*	P2897R7	16
std::atomic_ref::address()  (FTM)*	P2835R7	16
DR11/20: cv-qualified types in std::atomic and std::atomic_ref	P3323R1	16		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>  (FTM)*  (FTM)*	P3370R1	15* 16
<simd>: data-parallel types  (FTM)*	P1928R15 P3430R3 P2876R3 P3691R1 P3922R1 P3690R1 P3932R0 P4012R1	16 (partial)*
SIMD math operations	P1928R15 P3844R4
A utility for creating execution environments	P3325R5
constexpr for exception types, e.g. std::bad_alloc, std::bad_cast etc.  (FTM)*	P3068R6 P3378R2 P3842R2	16
std::simd::chunk	P3441R2	16
SIMD bit operations  (FTM)*	P2933R4
Interleaved std::complex values support in std::simd  (FTM)*	P2663R7
Defang and deprecate std::memory_order::consume	P3475R1
Put std::monostate in <utility>	P0472R3	15	21	19.50*
std::indirect  (FTM)*	P3019R14	16
std::polymorphic  (FTM)*	P3019R14	16
More constexpr containers and adaptors  (FTM)*	P3372R2	16 (partial)*
constexpr std::inplace_vector for non-trivial types  (FTM)*	P3074R7
std::ranges::as_input_view  (FTM)*	P3137R3 P3828R1	15* 16*
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
Library support for observable checkpoints  (FTM)*	P1494R5 P3641R0	16
<contracts>: Contract-violation handling support  (FTM)*	P2900R14 P3819R0	16
Standard library hardening	P3471R4 P3697R1 P3878R1	15 (partial)*		19.44* (partial)* 19.50* (partial)*
Freestanding library: <algorithm>, <numeric> and <random>  (FTM)*  (FTM)*  (FTM)*  (FTM)*  (FTM)*	P2976R1
DR20: Converting contiguous iterators to pointers	P3349R0	15		19.51*
<meta>: Reflection library support  (FTM)*	P2996R13 P3394R4 P3293R3 P3096R12 P3795R2 P4156R0	16 (partial)*
constexpr exceptions as error handling in reflection  (FTM)*	P3560R2	16
std::define_static_object, std::define_static_array, std::define_static_string  (FTM)*	P3491R3	16
std::simd::basic_vec and std::simd::basic_mask are range types	P3480R6	16
std::optional<T&>  (FTM)*  (FTM)*	P2988R12 P3836R2	16
std::string::subview()  (FTM)*	P3044R2	16
constexpr std::shared_ptr and friends  (FTM)*	P3037R6
Coroutine task types  (FTM)*	P3552R3 P3980R1 P3927R2 P3941R4 P4151R1
Async scopes: creating scopes for non-sequential concurrency  (FTM)*	P3149R11 P3815R1
Parallel scheduler  (FTM)*	P2079R10 P3804R2
High-quality sender diagnostics with constexpr exceptions	P3557R3
execution::write_env and execution::unstoppable sender adaptors	P3284R4
std::views::indices  (FTM)*	P3060R3	16
Parallel range algorithms  (FTM)*	P3179R9 P3709R2
Atomic floating-point min/max  (FTM)*	P3008R6
Atomic reduction operations  (FTM)*	P3111R8
SIMD permutation operations  (FTM)*	P2664R11
std::mdspan::at()	P3383R3	16
std::exception_ptr_cast()  (FTM)*	P2927R3 P3748R0 P3981R2	16 (partial)*
Standardized constexpr type ordering  (FTM)*	P2830R10 P3778R0 P4140R0	16
std::constant_wrapper  (FTM)*	P2781R9 P3978R3	16
Removed return type deduction in std::apply and added related type traits	P1317R2
Making type-erased allocator use in std::promise and std::packaged_task consistent	P3503R3			19.51*
std::filesystem::path::display_string() and std::filesystem::path::native_encoded_string()  (FTM)*	P2319R5
Making std::istream::ignore() less surprising	P3223R2	16		19.50*
Resolved inconsistencies in begin/end for std::valarray and std::initializer_list  (FTM)*  (FTM)*	P3016R6			19.51*
std::flat_meow fixes  (FTM)*  (FTM)*	P3567R2			19.51*
Making std::integer_sequence usable in structured bindings and expansion statements  (FTM)*	P1789R3	16
constexpr text formatting  (FTM)*	P3391R2
std::start_lifetime  (FTM)*	P3726R2
std::is_structural: type trait for detecting structural types  (FTM)*	P3856R8	16
std::constant_wrapper used as a std::function_ref constructor argument	P3948R1	16
Supporting signed char and unsigned char in random number generation	P4037R1
Implementation-defined replaceability detection of the contract- violation handler using feature macro  (FTM)*	P3886R0	16
DR20: Making user-defined constructors of view iterators/sentinels private	P3059R2	Yes
DR20: Filter view extensions for safer use  (FTM)*	P3725R3	16
C++26 feature	Paper(s)	GCC libstdc++	Clang libc++	MSVC STL	Apple Clang*

* - 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.

External links

1.	C++26 - Wikipedia