rollup merge of rust-lang#20042: alexcrichton/second-pass-ptr

This commit performs a second pass for stabilization over the `std::ptr` module.
The specific actions taken were:

* The `RawPtr` trait was renamed to `PtrExt`
* The `RawMutPtr` trait was renamed to `PtrMutExt`
* The module name `ptr` is now stable.
* These functions were all marked `#[stable]` with no modification:
  * `null`
  * `null_mut`
  * `swap`
  * `replace`
  * `read`
  * `write`
  * `PtrExt::is_null`
  * `PtrExt::is_not_null`
  * `PtrExt::offset`
* These functions remain unstable:
  * `as_ref`, `as_mut` - the return value of an `Option` is not fully expressive
                         as null isn't the only bad value, and it's unclear
                         whether we want to commit to these functions at this
                         time. The reference/lifetime semantics as written are
                         also problematic in how they encourage arbitrary
                         lifetimes.
  * `zero_memory` - This function is currently not used at all in the
                    distribution, and in general it plays a broader role in the
                    "working with unsafe pointers" story. This story is not yet
                    fully developed, so at this time the function remains
                    unstable for now.
  * `read_and_zero` - This function remains unstable for largely the same
                      reasons as `zero_memory`.
* These functions are now all deprecated:
  * `PtrExt::null` - call `ptr::null` or `ptr::null_mut` instead.
  * `PtrExt::to_uint` - use an `as` expression instead.

src/liballoc/arc.rs

@@ -80,7 +80,7 @@ use core::nonzero::NonZero;
 use core::ops::{Drop, Deref};
 use core::option::Option;
 use core::option::Option::{Some, None};
-use core::ptr::{mod, RawPtr};
+use core::ptr::{mod, PtrExt};
 use heap::deallocate;
 
 /// An atomically reference counted wrapper for shared state.

src/liballoc/heap.rs

@@ -8,7 +8,7 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
-use core::ptr::RawPtr;
+use core::ptr::PtrExt;
 
 // FIXME: #13996: mark the `allocate` and `reallocate` return value as `noalias`
 
@@ -371,7 +371,7 @@ mod imp {
 mod test {
     extern crate test;
     use self::test::Bencher;
-    use core::ptr::RawPtr;
+    use core::ptr::PtrExt;
     use heap;
 
     #[test]

src/liballoc/rc.rs

@@ -154,7 +154,7 @@ use core::nonzero::NonZero;
 use core::ops::{Deref, Drop};
 use core::option::Option;
 use core::option::Option::{Some, None};
-use core::ptr::{mod, RawPtr};
+use core::ptr::{mod, PtrExt};
 use core::result::Result;
 use core::result::Result::{Ok, Err};
 

src/libcollections/dlist.rs

@@ -95,7 +95,7 @@ impl<T> Rawlink<T> {
     /// Convert the `Rawlink` into an Option value
     fn resolve_immut<'a>(&self) -> Option<&'a T> {
         unsafe {
-            self.p.as_ref()
+            mem::transmute(self.p.as_ref())
         }
     }
 

src/libcollections/slice.rs

@@ -96,7 +96,7 @@ use core::mem::size_of;
 use core::mem;
 use core::ops::FnMut;
 use core::prelude::{Clone, Greater, Iterator, IteratorExt, Less, None, Option};
-use core::prelude::{Ord, Ordering, RawPtr, Some, range};
+use core::prelude::{Ord, Ordering, PtrExt, Some, range};
 use core::ptr;
 use core::slice as core_slice;
 use self::Direction::*;

src/libcollections/str.rs

@@ -1768,19 +1768,12 @@ impl StrExt for str {}
 
 #[cfg(test)]
 mod tests {
-    use std::iter::AdditiveIterator;
-    use std::iter::range;
-    use std::default::Default;
-    use std::char::Char;
-    use std::clone::Clone;
-    use std::cmp::{Ord, PartialOrd, Equiv};
-    use std::cmp::Ordering::{Equal, Greater, Less};
-    use std::option::Option::{mod, Some, None};
-    use std::result::Result::{Ok, Err};
-    use std::ptr::RawPtr;
-    use std::iter::{Iterator, IteratorExt, DoubleEndedIteratorExt};
+    use prelude::*;
 
-    use super::*;
+    use core::default::Default;
+    use core::iter::AdditiveIterator;
+    use super::{eq_slice, from_utf8, is_utf8, is_utf16, raw};
+    use super::truncate_utf16_at_nul;
     use super::MaybeOwned::{Owned, Slice};
     use std::slice::{AsSlice, SliceExt};
     use string::{String, ToString};

src/libcore/prelude.rs

@@ -57,7 +57,7 @@ pub use iter::{IteratorOrdExt, MutableDoubleEndedIterator, ExactSizeIterator};
 pub use num::{ToPrimitive, FromPrimitive};
 pub use option::Option;
 pub use option::Option::{Some, None};
-pub use ptr::RawPtr;
+pub use ptr::{PtrExt, MutPtrExt};
 pub use result::Result;
 pub use result::Result::{Ok, Err};
 pub use str::{Str, StrExt};