ptr::try_cast_aligned: fix doc

Author: mathisbot

library/core/src/ptr/const_ptr.rs

@@ -68,21 +68,23 @@ impl<T: ?Sized> *const T {
 
     /// Try to cast to a pointer of another type by checking aligment.
     ///
-    /// If the pointer is well aligned to the target type, it will be casted
-    /// to the target type. Otherwise, `None` is returned.
+    /// If the pointer is properly aligned to the target type, it will be
+    /// cast to the target type. Otherwise, `None` is returned.
     ///
     /// # Examples
     ///
     /// ```rust
     /// #![feature(pointer_try_cast_aligned)]
     ///
-    /// // On some platforms, the alignment of i32 is less than 4.
-    /// #[repr(align(4))]
-    /// struct AlignedI32(i32);
+    /// let aligned: *const u8 = 0x1000 as _;
+    ///
+    /// // i32 has at most 4-byte alignment, so this will succeed
+    /// assert!(aligned.try_cast_aligned::<i32>().is_some());
+    ///
+    /// let unaligned: *const u8 = 0x1001 as _;
     ///
-    /// // This pointer is aligned to 4 bytes
-    /// let ptr: *const u8 = 0x1000 as _;
-    /// assert!(ptr.try_cast_aligned::<AlignedI32>().is_some());
+    /// // i32 has at least 2-byte alignment, so this will fail
+    /// assert!(unaligned.try_cast_aligned::<i32>().is_none());
     /// ```
     #[unstable(feature = "pointer_try_cast_aligned", issue = "141221")]
     #[must_use = "this returns the result of the operation, \

library/core/src/ptr/mut_ptr.rs

@@ -50,21 +50,23 @@ impl<T: ?Sized> *mut T {
 
     /// Try to cast to a pointer of another type by checking aligment.
     ///
-    /// If the pointer is well aligned to the target type, it will be casted
-    /// to the target type. Otherwise, `None` is returned.
+    /// If the pointer is properly aligned to the target type, it will be
+    /// cast to the target type. Otherwise, `None` is returned.
     ///
     /// # Examples
     ///
     /// ```rust
     /// #![feature(pointer_try_cast_aligned)]
     ///
-    /// // On some platforms, the alignment of i32 is less than 4.
-    /// #[repr(align(4))]
-    /// struct AlignedI32(i32);
+    /// let aligned: *mut u8 = 0x1000 as _;
+    ///
+    /// // i32 has at most 4-byte alignment, so this will succeed
+    /// assert!(aligned.try_cast_aligned::<i32>().is_some());
+    ///
+    /// let unaligned: *mut u8 = 0x1001 as _;
     ///
-    /// // This pointer is aligned to 4 bytes
-    /// let ptr: *mut u8 = 0x1000 as _;
-    /// assert!(ptr.try_cast_aligned::<AlignedI32>().is_some());
+    /// // i32 has at least 2-byte alignment, so this will fail
+    /// assert!(unaligned.try_cast_aligned::<i32>().is_none());
     /// ```
     #[unstable(feature = "pointer_try_cast_aligned", issue = "141221")]
     #[must_use = "this returns the result of the operation, \

library/core/src/ptr/non_null.rs

@@ -490,23 +490,24 @@ impl<T: ?Sized> NonNull<T> {
 
     /// Try to cast to a pointer of another type by checking aligment.
     ///
-    /// If the pointer is well aligned to the target type, it will be casted
-    /// to the target type. Otherwise, `None` is returned.
+    /// If the pointer is properly aligned to the target type, it will be
+    /// cast to the target type. Otherwise, `None` is returned.
     ///
     /// # Examples
     ///
     /// ```rust
     /// #![feature(pointer_try_cast_aligned)]
     /// use std::ptr::NonNull;
     ///
-    /// // On some platforms, the alignment of i32 is less than 4.
-    /// #[repr(align(4))]
-    /// struct AlignedI32(i32);
+    /// let aligned: NonNull<u8> = NonNull::new(0x1000 as _).unwrap();
+    ///
+    /// // i32 has at most 4-byte alignment, so this will succeed
+    /// assert!(aligned.try_cast_aligned::<i32>().is_some());
+    ///
+    /// let unaligned: NonNull<u8> = NonNull::new(0x1001 as _).unwrap();
     ///
-    /// // This pointer is aligned to 4 bytes
-    /// let ptr: *mut u8 = 0x1000 as _;
-    /// let non_null = NonNull::new(ptr).unwrap();
-    /// assert!(non_null.try_cast_aligned::<AlignedI32>().is_some());
+    /// // i32 has at least 2-byte alignment, so this will fail
+    /// assert!(unaligned.try_cast_aligned::<i32>().is_none());
     /// ```
     #[unstable(feature = "pointer_try_cast_aligned", issue = "141221")]
     #[must_use = "this returns the result of the operation, \