fix dupe word typos

core/src/iter/sources/repeat_n.rs

@@ -20,7 +20,7 @@ use crate::mem::ManuallyDrop;
 /// #![feature(iter_repeat_n)]
 /// use std::iter;
 ///
-/// // four of the the number four:
+/// // four of the number four:
 /// let mut four_fours = iter::repeat_n(4, 4);
 ///
 /// assert_eq!(Some(4), four_fours.next());

core/src/str/pattern.rs

@@ -1894,7 +1894,7 @@ unsafe fn small_slice_eq(x: &[u8], y: &[u8]) -> bool {
     // Thus, derefencing both `px` and `py` in the loop below is safe.
     //
     // Moreover, we set `pxend` and `pyend` to be 4 bytes before the actual
-    // end of of `px` and `py`. Thus, the final dereference outside of the
+    // end of `px` and `py`. Thus, the final dereference outside of the
     // loop is guaranteed to be valid. (The final comparison will overlap with
     // the last comparison done in the loop for lengths that aren't multiples
     // of four.)

std/src/sync/mpmc/array.rs

@@ -225,7 +225,7 @@ impl<T> Channel<T> {
             let slot = unsafe { self.buffer.get_unchecked(index) };
             let stamp = slot.stamp.load(Ordering::Acquire);
 
-            // If the the stamp is ahead of the head by 1, we may attempt to pop.
+            // If the stamp is ahead of the head by 1, we may attempt to pop.
             if head + 1 == stamp {
                 let new = if index + 1 < self.cap {
                     // Same lap, incremented index.

std/src/thread/scoped.rs

@@ -46,7 +46,7 @@ impl ScopeData {
         // We check for 'overflow' with usize::MAX / 2, to make sure there's no
         // chance it overflows to 0, which would result in unsoundness.
         if self.num_running_threads.fetch_add(1, Ordering::Relaxed) > usize::MAX / 2 {
-            // This can only reasonably happen by mem::forget()'ing many many ScopedJoinHandles.
+            // This can only reasonably happen by mem::forget()'ing a lot of ScopedJoinHandles.
             self.decrement_num_running_threads(false);
             panic!("too many running threads in thread scope");
         }