fix the &mut _ patterns

src/test/bench/shootout-meteor.rs

@@ -118,7 +118,7 @@ fn transform(piece: Vec<(int, int)> , all: bool) -> Vec<Vec<(int, int)>> {
     // translating to (0, 0) as minimum coordinates.
     for cur_piece in res.iter_mut() {
         let (dy, dx) = *cur_piece.iter().min_by(|e| *e).unwrap();
-        for &(ref mut y, ref mut x) in cur_piece.iter_mut() {
+        for &mut (ref mut y, ref mut x) in cur_piece.iter_mut() {
             *y -= dy; *x -= dx;
         }
     }

src/test/compile-fail/issue-15756.rs

@@ -14,7 +14,7 @@ use std::slice::ChunksMut;
 fn dft_iter<'a, T>(arg1: Chunks<'a,T>, arg2: ChunksMut<'a,T>)
 {
     for
-    &something
+    &mut something
 //~^ ERROR the trait `core::marker::Sized` is not implemented for the type `[T]`
     in arg2
     {

src/test/compile-fail/mut-pattern-mismatched.rs

@@ -13,7 +13,7 @@ fn main() {
 
     // (separate lines to ensure the spans are accurate)
 
-     let &_ // ~ ERROR expected `&mut isize`, found `&_`
+     let &_ //~ ERROR expected `&mut isize`, found `&_`
         = foo;
     let &mut _ = foo;
 

src/test/compile-fail/pattern-bindings-after-at.rs

@@ -15,7 +15,7 @@ enum Option<T> {
 
 fn main() {
     match &mut Some(1i) {
-        ref mut z @ &Some(ref a) => {
+        ref mut z @ &mut Some(ref a) => {
         //~^ ERROR pattern bindings are not allowed after an `@`
             **z = None;
             println!("{}", *a);

src/test/run-pass/drop-trait-enum.rs

@@ -36,13 +36,13 @@ enum Foo {
 impl Drop for Foo {
     fn drop(&mut self) {
         match self {
-            &Foo::SimpleVariant(ref mut sender) => {
+            &mut Foo::SimpleVariant(ref mut sender) => {
                 sender.send(Message::DestructorRan).unwrap();
             }
-            &Foo::NestedVariant(_, _, ref mut sender) => {
+            &mut Foo::NestedVariant(_, _, ref mut sender) => {
                 sender.send(Message::DestructorRan).unwrap();
             }
-            &Foo::FailingVariant { .. } => {
+            &mut Foo::FailingVariant { .. } => {
                 panic!("Failed");
             }
         }

src/test/run-pass/issue-16774.rs

@@ -36,7 +36,7 @@ impl Deref for X {
 
 impl DerefMut for X {
     fn deref_mut(&mut self) -> &mut int {
-        let &X(box ref mut x) = self;
+        let &mut X(box ref mut x) = self;
         x
     }
 }