wip: CR fixes

Author: yotamofek

library/core/src/ptr/const_ptr.rs

@@ -1783,8 +1783,8 @@ impl<T, const N: usize> *const [T; N] {
     /// assert_eq!(arr.as_ptr(), ptr::null());
     /// ```
     #[inline]
-    #[unstable(feature = "array_ptr_get", issue = "119411")]
-    #[rustc_const_unstable(feature = "array_ptr_get", issue = "119411")]
+    #[unstable(feature = "array_ptr_get", issue = "119834")]
+    #[rustc_const_unstable(feature = "array_ptr_get", issue = "119834")]
     pub const fn as_ptr(self) -> *const T {
         self as *const T
     }
@@ -1801,11 +1801,10 @@ impl<T, const N: usize> *const [T; N] {
     /// assert_eq!(slice.len(), 3);
     /// ```
     #[inline]
-    #[unstable(feature = "array_ptr_get", issue = "119411")]
-    #[rustc_const_unstable(feature = "array_ptr_get", issue = "119411")]
+    #[unstable(feature = "array_ptr_get", issue = "119834")]
+    #[rustc_const_unstable(feature = "array_ptr_get", issue = "119834")]
     pub const fn as_slice(self) -> *const [T] {
-        // SAFETY: `N` is the length of the array, so the pointer is always in-bounds.
-        unsafe { slice::from_raw_parts(self.as_ptr(), N) }
+        slice_from_raw_parts(self.as_ptr(), N)
     }
 }
 

library/core/src/ptr/mut_ptr.rs

@@ -2198,7 +2198,7 @@ impl<T> *mut [T] {
 impl<T, const N: usize> *mut [T; N] {
     /// Returns a raw pointer to the array's buffer.
     ///
-    /// This is equivalent to casting `self` to `*const T`, but more type-safe.
+    /// This is equivalent to casting `self` to `*mut T`, but more type-safe.
     ///
     /// # Examples
     ///
@@ -2210,12 +2210,13 @@ impl<T, const N: usize> *mut [T; N] {
     /// assert_eq!(arr.as_mut_ptr(), ptr::null_mut());
     /// ```
     #[inline]
-    #[unstable(feature = "array_ptr_get", issue = "119411")]
-    pub fn as_mut_ptr(self) -> *mut T {
+    #[unstable(feature = "array_ptr_get", issue = "119834")]
+    #[rustc_const_unstable(feature = "array_ptr_get", issue = "119834")]
+    pub const fn as_mut_ptr(self) -> *mut T {
         self as *mut T
     }
 
-    /// Returns a raw pointer to a unique slice containing the entire array.
+    /// Returns a raw pointer to a mutable slice containing the entire array.
     ///
     /// # Examples
     ///
@@ -2230,10 +2231,10 @@ impl<T, const N: usize> *mut [T; N] {
     /// assert_eq!(arr, [3, 4, 5]);
     /// ```
     #[inline]
-    #[unstable(feature = "array_ptr_get", issue = "119411")]
-    pub fn as_mut_slice(self) -> *mut [T] {
-        // SAFETY: `N` is the length of the array, so the pointer is always in-bounds.
-        unsafe { slice::from_raw_parts_mut(self.as_mut_ptr(), N) }
+    #[unstable(feature = "array_ptr_get", issue = "119834")]
+    #[rustc_const_unstable(feature = "array_ptr_get", issue = "119834")]
+    pub const fn as_mut_slice(self) -> *mut [T] {
+        slice_from_raw_parts_mut(self.as_mut_ptr(), N)
     }
 }
 

library/core/tests/lib.rs

@@ -1,5 +1,6 @@
 #![feature(alloc_layout_extra)]
 #![feature(array_chunks)]
+#![feature(array_ptr_get)]
 #![feature(array_windows)]
 #![feature(ascii_char)]
 #![feature(ascii_char_variants)]
@@ -49,6 +50,7 @@
 #![feature(sort_internals)]
 #![feature(slice_take)]
 #![feature(slice_from_ptr_range)]
+#![feature(slice_ptr_len)]
 #![feature(slice_split_once)]
 #![feature(split_as_slice)]
 #![feature(maybe_uninit_uninit_array)]

library/core/tests/ptr.rs

@@ -1142,3 +1142,16 @@ fn test_const_copy() {
         assert!(*ptr2 == 1);
     };
 }
+
+#[test]
+fn test_null_array_as_slice() {
+    let arr: *mut [u8; 4] = null_mut();
+    let ptr: *mut [u8] = arr.as_mut_slice();
+    assert!(ptr.is_null());
+    assert_eq!(ptr.len(), 4);
+
+    let arr: *const [u8; 4] = null();
+    let ptr: *const [u8] = arr.as_slice();
+    assert!(ptr.is_null());
+    assert_eq!(ptr.len(), 4);
+}