bjoernager/rust
bjoernager/rust
1
Fork 0
Code Activity

reference NonNull::dangling

Browse source
This commit is contained in:
Ralf Jung 2020-11-20 10:25:59 +01:00
parent 0f572a9810
commit a7677f7714
2 changed files with 12 additions and 9 deletions
Download patch file Download diff file Expand all files Collapse all files

10
library/alloc/src/boxed.rs
View file

@ -62,10 +62,12 @@
//! T` obtained from [`Box::<T>::into_raw`] may be deallocated using the
//! [`Global`] allocator with [`Layout::for_value(&*value)`].
//!
//! For zero-sized values, the `Box` pointer still has to be [valid] for reads and writes and
//! sufficiently aligned. In particular, casting any aligned non-zero integer literal to a raw
//! pointer produces a valid pointer, but a pointer pointing into previously allocated memory that
//! since got freed is not valid.
//! For zero-sized values, the `Box` pointer still has to be [valid] for reads
//! and writes and sufficiently aligned. In particular, casting any aligned
//! non-zero integer literal to a raw pointer produces a valid pointer, but a
//! pointer pointing into previously allocated memory that since got freed is
//! not valid. The recommended way to build a Box to a ZST if `Box::new` cannot
//! be used is to use [`ptr::NonNull::dangling`].
//!
//! So long as `T: Sized`, a `Box<T>` is guaranteed to be represented
//! as a single pointer and is also ABI-compatible with C pointers