- Title
- <coroutine> is freestanding, but uses std::hash which is not
- Status
- new
- Section
- [coroutine.syn]
- Submitter
- Jonathan Wakely
Created on 2021-12-17.00:00:00 last changed 3 weeks ago
Messages
Date: 2025-11-11.14:48:16
Proposed resolution:
This wording is relative to ISO/IEC 14882:2020(E).
- Modify [coroutine.handle.hash] as indicated:
template<class P> struct hash<coroutine_handle<P>>;
-1- The specialization is enabled ([unord.hash]) in a hosted implementation.
Date: 2025-11-15.00:00:00
[ 2025-11-11; Jonathan adds wording for C++20. ]
This wording would resolve the defect for C++20, but the issue should be closed as Resolved in C++23.
Date: 2022-01-15.00:00:00
[ 2022-01-30; Reflector poll ]
Set priority to 3 after reflector poll. Would be resolved by P1642 for C++23, but it's still a defect in C++20.
Date: 2021-12-17.00:00:00
The <coroutine> header is required for freestanding implementations, but it defines a specialization of std::hash, which is not required for freestanding implementations.
Presumably we should make the std::hash specialization conditionally present.
| History | |||
|---|---|---|---|
| Date | User | Action | Args |
| 2025-11-11 14:48:16 | admin | set | messages: + msg15725 |
| 2025-11-11 14:48:16 | admin | set | messages: + msg15724 |
| 2022-01-30 17:05:36 | admin | set | messages: + msg12325 |
| 2021-12-17 00:00:00 | admin | create | |