document that the null pointer has the 0 address

rust-lang · Oct 20, 2023 · 98d54da · 98d54da
1 parent 274455a
commit 98d54da
Showing 1 changed file with 10 additions and 0 deletions.
diff --git a/library/core/src/ptr/mod.rs b/library/core/src/ptr/mod.rs
@@ -505,13 505,18 @@ pub unsafe fn drop_in_place<T: ?Sized>(to_drop: *mut T) {
 
 /// Creates a null raw pointer.
 ///
 /// This function is equivalent to zero-initializing the pointer:
 /// `MaybeUninit::<*const T>::zeroed().assume_init()`.
 /// The resulting pointer has the address 0.
 ///
 /// # Examples
 ///
 /// ```
 /// use std::ptr;
 ///
 /// let p: *const i32 = ptr::null();
 /// assert!(p.is_null());
 /// assert_eq!(p as usize, 0); // this pointer has the address 0
 /// ```
 #[inline(always)]
 #[must_use]
@@ -526,13 531,18 @@ pub const fn null<T: ?Sized Thin>() -> *const T {
 
 /// Creates a null mutable raw pointer.
 ///
 /// This function is equivalent to zero-initializing the pointer:
 /// `MaybeUninit::<*mut T>::zeroed().assume_init()`.
 /// The resulting pointer has the address 0.
 ///
 /// # Examples
 ///
 /// ```
 /// use std::ptr;
 ///
 /// let p: *mut i32 = ptr::null_mut();
 /// assert!(p.is_null());
 /// assert_eq!(p as usize, 0); // this pointer has the address 0
 /// ```
 #[inline(always)]
 #[must_use]