diff --git a/example/example.rs b/example/example.rs
index 220554550f1..d7fbb932240 100644
--- a/example/example.rs
+++ b/example/example.rs
@@ -77,7 +77,7 @@ fn debug_tuple() -> DebugTuple {
 }
 
 fn size_of<T>() -> usize {
-    unsafe { intrinsics::size_of::<T>() }
+    intrinsics::size_of::<T>()
 }
 
 fn use_size_of() -> usize {
@@ -93,10 +93,10 @@ unsafe fn use_copy_intrinsic_ref(src: *const u8, dst: *mut u8) {
     copy2(src, dst, 1);
 }
 
-const Abc: u8 = 6 * 7;
+const ABC: u8 = 6 * 7;
 
 fn use_const() -> u8 {
-    Abc
+    ABC
 }
 
 pub fn call_closure_3arg() {
@@ -120,7 +120,7 @@ impl<'a, 'b> FnOnce<(&'a &'b [u16],)> for IsNotEmpty {
 
 impl<'a, 'b> FnMut<(&'a &'b [u16],)> for IsNotEmpty {
     #[inline]
-    extern "rust-call" fn call_mut(&mut self, arg: (&'a &'b [u16],)) -> (u8, u8) {
+    extern "rust-call" fn call_mut(&mut self, _arg: (&'a &'b [u16],)) -> (u8, u8) {
         (0, 42)
     }
 }
diff --git a/example/mini_core_hello_world.rs b/example/mini_core_hello_world.rs
index 2e39a3aae86..e486afdbaa0 100644
--- a/example/mini_core_hello_world.rs
+++ b/example/mini_core_hello_world.rs
@@ -103,8 +103,8 @@ struct Unique<T: ?Sized> {
 
 impl<T: ?Sized, U: ?Sized> CoerceUnsized<Unique<U>> for Unique<T> where T: Unsize<U> {}
 
-fn take_f32(f: f32) {}
-fn take_unique(u: Unique<()>) {}
+fn take_f32(_f: f32) {}
+fn take_unique(_u: Unique<()>) {}
 
 fn main() {
     take_unique(Unique {
diff --git a/src/pretty_clif.rs b/src/pretty_clif.rs
index 7107f62a27d..a7a9c7a3306 100644
--- a/src/pretty_clif.rs
+++ b/src/pretty_clif.rs
@@ -203,7 +203,7 @@ impl<'a, 'tcx: 'a, B: Backend + 'a> FunctionCx<'a, 'tcx, B> {
             Ok(mut file) => {
                 let target_triple: ::target_lexicon::Triple = self.tcx.sess.target.target.llvm_target.parse().unwrap();
                 writeln!(file, "test compile").unwrap();
-                writeln!(file, "set is_pic");
+                writeln!(file, "set is_pic").unwrap();
                 writeln!(file, "target {}", target_triple).unwrap();
                 writeln!(file, "").unwrap();
                 file.write(clif.as_bytes()).unwrap();