Undo changes to core::ptr

Author: Paul Liétar

src/libcore/ptr.rs

@@ -485,9 +485,8 @@ impl<T: ?Sized> *const T {
     /// ```
     #[stable(feature = "rust1", since = "1.0.0")]
     #[inline]
-    pub fn is_null(self) -> bool {
-        // cast to () pointer, as T may not be sized
-        self as *const () == null()
+    pub fn is_null(self) -> bool where T: Sized {
+        self == null()
     }
 
     /// Returns `None` if the pointer is null, or else returns a reference to
@@ -518,7 +517,7 @@ impl<T: ?Sized> *const T {
     /// ```
     #[stable(feature = "ptr_as_ref", since = "1.9.0")]
     #[inline]
-    pub unsafe fn as_ref<'a>(self) -> Option<&'a T> {
+    pub unsafe fn as_ref<'a>(self) -> Option<&'a T> where T: Sized {
         if self.is_null() {
             None
         } else {
@@ -1117,9 +1116,8 @@ impl<T: ?Sized> *mut T {
     /// ```
     #[stable(feature = "rust1", since = "1.0.0")]
     #[inline]
-    pub fn is_null(self) -> bool {
-        // cast to () pointer, as T may not be sized
-        self as *mut () == null_mut()
+    pub fn is_null(self) -> bool where T: Sized {
+        self == null_mut()
     }
 
     /// Returns `None` if the pointer is null, or else returns a reference to
@@ -1150,7 +1148,7 @@ impl<T: ?Sized> *mut T {
     /// ```
     #[stable(feature = "ptr_as_ref", since = "1.9.0")]
     #[inline]
-    pub unsafe fn as_ref<'a>(self) -> Option<&'a T> {
+    pub unsafe fn as_ref<'a>(self) -> Option<&'a T> where T: Sized {
         if self.is_null() {
             None
         } else {
@@ -1274,7 +1272,7 @@ impl<T: ?Sized> *mut T {
     /// ```
     #[stable(feature = "ptr_as_ref", since = "1.9.0")]
     #[inline]
-    pub unsafe fn as_mut<'a>(self) -> Option<&'a mut T> {
+    pub unsafe fn as_mut<'a>(self) -> Option<&'a mut T> where T: Sized {
         if self.is_null() {
             None
         } else {