ci: enable clippy lints (#1335)

tokio-timer/src/timer/atomic_stack.rs

@@ -115,7 +115,7 @@ impl Iterator for AtomicStackEntries {
 
 impl Drop for AtomicStackEntries {
     fn drop(&mut self) {
-        while let Some(entry) = self.next() {
+        for entry in self {
             // Flag the entry as errored
             entry.error();
         }

tokio-timer/src/timer/entry.rs

@@ -125,8 +125,9 @@ impl Entry {
     }
 
     /// Only called by `Registration`
-    pub fn time_mut(&self) -> &mut Time {
-        unsafe { &mut *self.time.get() }
+    #[allow(clippy::mut_from_ref)] // https://github.com/rust-lang/rust-clippy/issues/4281
+    pub unsafe fn time_mut(&self) -> &mut Time {
+        &mut *self.time.get()
     }
 
     /// Returns `true` if the `Entry` is currently associated with a timer

tokio-timer/src/timer/registration.rs

@@ -38,7 +38,9 @@ impl Registration {
     }
 
     pub fn reset(&mut self, deadline: Instant) {
-        self.entry.time_mut().deadline = deadline;
+        unsafe {
+            self.entry.time_mut().deadline = deadline;
+        }
         Entry::reset(&mut self.entry);
     }
 
@@ -46,7 +48,9 @@ impl Registration {
     #[cfg(feature = "async-traits")]
     pub fn reset_timeout(&mut self) {
         let deadline = crate::clock::now() + self.entry.time_ref().duration;
-        self.entry.time_mut().deadline = deadline;
+        unsafe {
+            self.entry.time_mut().deadline = deadline;
+        }
         Entry::reset(&mut self.entry);
     }