Replace 0 as *const/mut T with ptr::null/null_mut()

src/libstd/sync/mpsc/mpsc_queue.rs

@@ -46,6 +46,7 @@ use core::prelude::*;
 
 use alloc::boxed::Box;
 use core::mem;
+use core::ptr;
 use core::cell::UnsafeCell;
 
 use sync::atomic::{AtomicPtr, Ordering};
@@ -82,7 +83,7 @@ unsafe impl<T:Send> Sync for Queue<T> { }
 impl<T> Node<T> {
     unsafe fn new(v: Option<T>) -> *mut Node<T> {
         mem::transmute(box Node {
-            next: AtomicPtr::new(0 as *mut Node<T>),
+            next: AtomicPtr::new(ptr::null_mut()),
             value: v,
         })
     }

src/libstd/sync/mpsc/select.rs

@@ -59,6 +59,7 @@ use core::prelude::*;
 use core::cell::Cell;
 use core::marker;
 use core::mem;
+use core::ptr;
 use core::uint;
 
 use sync::mpsc::{Receiver, RecvError};
@@ -130,8 +131,8 @@ impl Select {
     pub fn new() -> Select {
         Select {
             marker1: marker::NoSend,
-            head: 0 as *mut Handle<'static, ()>,
-            tail: 0 as *mut Handle<'static, ()>,
+            head: ptr::null_mut(),
+            tail: ptr::null_mut(),
             next_id: Cell::new(1),
         }
     }
@@ -144,8 +145,8 @@ impl Select {
     #[cfg(not(stage0))] // NOTE remove cfg after next snapshot
     pub fn new() -> Select {
         Select {
-            head: 0 as *mut Handle<'static, ()>,
-            tail: 0 as *mut Handle<'static, ()>,
+            head: ptr::null_mut(),
+            tail: ptr::null_mut(),
             next_id: Cell::new(1),
         }
     }
@@ -159,8 +160,8 @@ impl Select {
         Handle {
             id: id,
             selector: self,
-            next: 0 as *mut Handle<'static, ()>,
-            prev: 0 as *mut Handle<'static, ()>,
+            next: ptr::null_mut(),
+            prev: ptr::null_mut(),
             added: false,
             rx: rx,
             packet: rx,
@@ -325,8 +326,8 @@ impl<'rx, T: Send> Handle<'rx, T> {
             (*self.next).prev = self.prev;
         }
 
-        self.next = 0 as *mut Handle<'static, ()>;
-        self.prev = 0 as *mut Handle<'static, ()>;
+        self.next = ptr::null_mut();
+        self.prev = ptr::null_mut();
 
         self.added = false;
     }

src/libstd/sync/mpsc/spsc_queue.rs

@@ -39,6 +39,7 @@ use core::prelude::*;
 
 use alloc::boxed::Box;
 use core::mem;
+use core::ptr;
 use core::cell::UnsafeCell;
 
 use sync::atomic::{AtomicPtr, AtomicUsize, Ordering};
@@ -82,7 +83,7 @@ impl<T: Send> Node<T> {
         unsafe {
             mem::transmute(box Node {
                 value: None,
-                next: AtomicPtr::new(0 as *mut Node<T>),
+                next: AtomicPtr::new(ptr::null_mut::<Node<T>>()),
             })
         }
     }
@@ -131,7 +132,7 @@ impl<T: Send> Queue<T> {
             let n = self.alloc();
             assert!((*n).value.is_none());
             (*n).value = Some(t);
-            (*n).next.store(0 as *mut Node<T>, Ordering::Relaxed);
+            (*n).next.store(ptr::null_mut(), Ordering::Relaxed);
             (**self.head.get()).next.store(n, Ordering::Release);
             *self.head.get() = n;
         }

src/libstd/sync/mpsc/sync.rs

@@ -40,6 +40,7 @@ use self::Blocker::*;
 
 use vec::Vec;
 use core::mem;
+use core::ptr;
 
 use sync::atomic::{Ordering, AtomicUsize};
 use sync::mpsc::blocking::{self, WaitToken, SignalToken};
@@ -145,8 +146,8 @@ impl<T: Send> Packet<T> {
                 cap: cap,
                 canceled: None,
                 queue: Queue {
-                    head: 0 as *mut Node,
-                    tail: 0 as *mut Node,
+                    head: ptr::null_mut(),
+                    tail: ptr::null_mut(),
                 },
                 buf: Buffer {
                     buf: range(0, cap + if cap == 0 {1} else {0}).map(|_| None).collect(),
@@ -160,7 +161,7 @@ impl<T: Send> Packet<T> {
     // wait until a send slot is available, returning locked access to
     // the channel state.
     fn acquire_send_slot(&self) -> MutexGuard<State<T>> {
-        let mut node = Node { token: None, next: 0 as *mut Node };
+        let mut node = Node { token: None, next: ptr::null_mut() };
         loop {
             let mut guard = self.lock.lock().unwrap();
             // are we ready to go?
@@ -343,8 +344,8 @@ impl<T: Send> Packet<T> {
             Vec::new()
         };
         let mut queue = mem::replace(&mut guard.queue, Queue {
-            head: 0 as *mut Node,
-            tail: 0 as *mut Node,
+            head: ptr::null_mut(),
+            tail: ptr::null_mut(),
         });
 
         let waiter = match mem::replace(&mut guard.blocker, NoneBlocked) {
@@ -453,7 +454,7 @@ impl Queue {
     fn enqueue(&mut self, node: &mut Node) -> WaitToken {
         let (wait_token, signal_token) = blocking::tokens();
         node.token = Some(signal_token);
-        node.next = 0 as *mut Node;
+        node.next = ptr::null_mut();
 
         if self.tail.is_null() {
             self.head = node as *mut Node;
@@ -475,10 +476,10 @@ impl Queue {
         let node = self.head;
         self.head = unsafe { (*node).next };
         if self.head.is_null() {
-            self.tail = 0 as *mut Node;
+            self.tail = ptr::null_mut();
         }
         unsafe {
-            (*node).next = 0 as *mut Node;
+            (*node).next = ptr::null_mut();
             Some((*node).token.take().unwrap())
         }
     }