Fixed all unnecessary muts in language core

3 files changed, 4 insertions, 4 deletions

diff --git a/src/libstd/collections/hash/map.rs b/src/libstd/collections/hash/map.rs
index 12241b3f881..7e2229a8f84 100644
--- a/src/libstd/collections/hash/map.rs
+++ b/src/libstd/collections/hash/map.rs
@@ -1618,7 +1618,7 @@ impl<'a, K, V, S> IntoIterator for &'a mut HashMap<K, V, S>
     type Item = (&'a K, &'a mut V);
     type IntoIter = IterMut<'a, K, V>;
 
-    fn into_iter(mut self) -> IterMut<'a, K, V> {
+    fn into_iter(self) -> IterMut<'a, K, V> {
         self.iter_mut()
     }
 }
diff --git a/src/libstd/sync/once.rs b/src/libstd/sync/once.rs
index d9edf5d1254..bb18fe95a9d 100644
--- a/src/libstd/sync/once.rs
+++ b/src/libstd/sync/once.rs
@@ -267,7 +267,7 @@ impl Once {
     #[cold]
     fn call_inner(&'static self,
                   ignore_poisoning: bool,
-                  mut init: &mut FnMut(bool)) {
+                  init: &mut FnMut(bool)) {
         let mut state = self.state.load(Ordering::SeqCst);
 
         'outer: loop {
diff --git a/src/libstd/sys/unix/rand.rs b/src/libstd/sys/unix/rand.rs
index 77ebad4e344..1f56a299407 100644
--- a/src/libstd/sys/unix/rand.rs
+++ b/src/libstd/sys/unix/rand.rs
@@ -12,13 +12,13 @@ pub use self::imp::OsRng;
 
 use mem;
 
-fn next_u32(mut fill_buf: &mut FnMut(&mut [u8])) -> u32 {
+fn next_u32(fill_buf: &mut FnMut(&mut [u8])) -> u32 {
     let mut buf: [u8; 4] = [0; 4];
     fill_buf(&mut buf);
     unsafe { mem::transmute::<[u8; 4], u32>(buf) }
 }
 
-fn next_u64(mut fill_buf: &mut FnMut(&mut [u8])) -> u64 {
+fn next_u64(fill_buf: &mut FnMut(&mut [u8])) -> u64 {
     let mut buf: [u8; 8] = [0; 8];
     fill_buf(&mut buf);
     unsafe { mem::transmute::<[u8; 8], u64>(buf) }