diff --git a/library/core/src/ptr/mod.rs b/library/core/src/ptr/mod.rs index d2e680ecd20b5..6b1e63e0cfaae 100644 --- a/library/core/src/ptr/mod.rs +++ b/library/core/src/ptr/mod.rs @@ -26,6 +26,7 @@ //! some memory happens to exist at that address and gets deallocated. This corresponds to writing //! your own allocator: allocating zero-sized objects is not very hard. The canonical way to //! obtain a pointer that is valid for zero-sized accesses is [`NonNull::dangling`]. +//FIXME: mention `ptr::invalid` above, once it is stable. //! * All accesses performed by functions in this module are *non-atomic* in the sense //! of [atomic operations] used to synchronize between threads. This means it is //! undefined behavior to perform two concurrent accesses to the same location from different @@ -557,8 +558,8 @@ pub const fn null_mut() -> *mut T { /// Creates an invalid pointer with the given address. /// -/// This is *currently* equivalent to `addr as *const T` but it expresses the intended semantic -/// more clearly, and may become important under future memory models. +/// This is different from `addr as *const T`, which creates a pointer that picks up a previously +/// exposed provenance. See [`from_exposed_addr`] for more details on that operation. /// /// The module's top-level documentation discusses the precise meaning of an "invalid" /// pointer but essentially this expresses that the pointer is not associated @@ -566,7 +567,7 @@ pub const fn null_mut() -> *mut T { /// /// This pointer will have no provenance associated with it and is therefore /// UB to read/write/offset. This mostly exists to facilitate things -/// like ptr::null and NonNull::dangling which make invalid pointers. +/// like `ptr::null` and `NonNull::dangling` which make invalid pointers. /// /// (Standard "Zero-Sized-Types get to cheat and lie" caveats apply, although it /// may be desirable to give them their own API just to make that 100% clear.) @@ -588,8 +589,8 @@ pub const fn invalid(addr: usize) -> *const T { /// Creates an invalid mutable pointer with the given address. /// -/// This is *currently* equivalent to `addr as *mut T` but it expresses the intended semantic -/// more clearly, and may become important under future memory models. +/// This is different from `addr as *mut T`, which creates a pointer that picks up a previously +/// exposed provenance. See [`from_exposed_addr_mut`] for more details on that operation. /// /// The module's top-level documentation discusses the precise meaning of an "invalid" /// pointer but essentially this expresses that the pointer is not associated @@ -597,7 +598,7 @@ pub const fn invalid(addr: usize) -> *const T { /// /// This pointer will have no provenance associated with it and is therefore /// UB to read/write/offset. This mostly exists to facilitate things -/// like ptr::null and NonNull::dangling which make invalid pointers. +/// like `ptr::null` and `NonNull::dangling` which make invalid pointers. /// /// (Standard "Zero-Sized-Types get to cheat and lie" caveats apply, although it /// may be desirable to give them their own API just to make that 100% clear.)