C++26
Status note: This article is compiled from publicly available materials as of 2026-06-02. The C++26 standardization process, proposal acceptance status, and compiler support change rapidly. Verify against WG21 drafts, cppreference compiler support, and compiler release notes before merging.
Features Already in the Working Draft
Contracts
Language-level support for preconditions, postconditions, and assertions:
int sqrt(int n)
pre (n >= 0)
post (r: r * r <= n)
{
// ...
}Reflection
Compile-time reflection capabilities — querying type information, member lists, enum values, etc., at compile time. A paradigm shift for C++ metaprogramming. (P2996R7 has been accepted)
Pattern Matching
The inspect expression, similar to Rust's match, especially useful for types like variant and optional.
std::simd
Standardized SIMD types and operations for writing portable vectorized code. (P1928)
Senders/Receivers
A standardized asynchronous execution framework, more flexible and controllable than std::async. (P2300)
constexpr Extensions
More standard library functions available at compile time.
Feature Status Classification
| Status | Meaning | Example |
|---|---|---|
| In working draft | Accepted for C++26 | Reflection (P2996), Contracts |
| Voted in | Passed WG21 vote, awaiting merge | Senders/Receivers (P2300) |
| Still evolving | Proposal still under revision | P3394 (annotations), P3436 |
| Deferred to C++29 | Did not meet C++26 timeline | Some pattern matching details |
| Experimental only | Compiler experimental branch support | Some constexpr extensions |
Compiler Support Status
| Compiler | Reflection | Contracts | std::simd | Notes |
|---|---|---|---|---|
| Clang/LLVM | Experimental (-freflection) | In progress | N/A | Reference implementation |
| GCC | Experimental branch | In progress | <experimental/simd> | GCC 14+ |
| MSVC | In progress | In progress | N/A | — |
Status Note
C++26 features are still evolving. This document tracks the latest developments, but content may lag behind the standard committee's latest decisions.
Reference sources: