libcore: Remove mutable fields from pipes

src/libstd/comm.rs

@@ -72,7 +72,7 @@ impl<T:Owned,U:Owned> Peekable<U> for DuplexStream<T, U> {
 }
 
 impl<T:Owned,U:Owned> Selectable for DuplexStream<T, U> {
-    fn header(&self) -> *pipes::PacketHeader {
+    fn header(&mut self) -> *mut pipes::PacketHeader {
         self.port.header()
     }
 }

src/libstd/timer.rs

@@ -14,10 +14,11 @@ use uv;
 use uv::iotask;
 use uv::iotask::IoTask;
 
-use core::libc;
-use core::libc::c_void;
 use core::cast::transmute;
+use core::cast;
 use core::comm::{stream, Chan, SharedChan, Port, select2i};
+use core::libc::c_void;
+use core::libc;
 
 /**
  * Wait for timeout period then send provided value over a channel
@@ -120,22 +121,28 @@ pub fn sleep(iotask: &IoTask, msecs: uint) {
 pub fn recv_timeout<T:Copy + Owned>(iotask: &IoTask,
                                    msecs: uint,
                                    wait_po: &Port<T>)
-                                -> Option<T> {
-    let (timeout_po, timeout_ch) = stream::<()>();
+                                   -> Option<T> {
+    let mut (timeout_po, timeout_ch) = stream::<()>();
     delayed_send(iotask, msecs, &timeout_ch, ());
-    // FIXME: This could be written clearer (#2618)
-    either::either(
-        |_| {
-            None
-        }, |_| {
-            Some(wait_po.recv())
-        }, &select2i(&timeout_po, wait_po)
-    )
+
+    // XXX: Workaround due to ports and channels not being &mut. They should
+    // be.
+    unsafe {
+        let wait_po = cast::transmute_mut(wait_po);
+
+        // FIXME: This could be written clearer (#2618)
+        either::either(
+            |_| {
+                None
+            }, |_| {
+                Some(wait_po.recv())
+            }, &select2i(&mut timeout_po, wait_po)
+        )
+    }
 }
 
 // INTERNAL API
-extern fn delayed_send_cb(handle: *uv::ll::uv_timer_t,
-                                status: libc::c_int) {
+extern fn delayed_send_cb(handle: *uv::ll::uv_timer_t, status: libc::c_int) {
     unsafe {
         debug!(
             "delayed_send_cb handle %? status %?", handle, status);