nordic-dev.net/rust
nordic-dev.net/rust
2
0
Fork 0
mirror of https://github.com/rust-lang/rust.git synced 2024-10-31 22:41:50 +00:00
Code Issues Packages Projects Releases Wiki Activity

Clarify the lifetimes of allocations returned by the Allocator trait

Browse Source 
The previous definition (accidentally) disallowed the implementation of
stack-based allocators whose memory would become invalid once the
lifetime of the allocator type ended.

This also ensures the validity of the following blanket implementation:
```rust
impl<A: Allocator> Allocator for &'_ A {}
```
This commit is contained in:
Amanieu d'Antras 2023-12-12 19:55:43 +00:00
parent b17491c8f6
commit fb5ed2986e
1 changed files with 4 additions and 2 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

6
library/core/src/alloc/mod.rs
View File

@ -95,8 +95,10 @@ impl fmt::Display for AllocError {
/// # Safety
///
/// * Memory blocks returned from an allocator that are [*currently allocated*] must point to
/// valid memory and retain their validity while they are [*currently allocated*] and at
/// least one of the instance and all of its clones has not been dropped.
/// valid memory and retain their validity while they are [*currently allocated*] and the shorter
/// of:
/// - the borrow-checker lifetime of the allocator type itself.
/// - as long as at least one of the instance and all of its clones has not been dropped.
///
/// * copying, cloning, or moving the allocator must not invalidate memory blocks returned from this
/// allocator. A copied or cloned allocator must behave like the same allocator, and