diff --git a/src/librustc_trans/lib.rs b/src/librustc_trans/lib.rs
index 2421b39b8bb..05b1a86b72b 100644
--- a/src/librustc_trans/lib.rs
+++ b/src/librustc_trans/lib.rs
@@ -25,6 +25,7 @@
 #![feature(default_type_params, globs, import_shadowing, macro_rules, phase, quote)]
 #![feature(slicing_syntax, unsafe_destructor)]
 #![feature(rustc_diagnostic_macros)]
+#![feature(unboxed_closures)]
 
 extern crate arena;
 extern crate flate;
diff --git a/src/librustc_trans/trans/_match.rs b/src/librustc_trans/trans/_match.rs
index 1ed06938e95..7a7a708fcc5 100644
--- a/src/librustc_trans/trans/_match.rs
+++ b/src/librustc_trans/trans/_match.rs
@@ -771,7 +771,7 @@ fn pick_column_to_specialize(def_map: &DefMap, m: &[Match]) -> Option<uint> {
         }
     };
 
-    let column_contains_any_nonwild_patterns: |&uint| -> bool = |&col| {
+    let column_contains_any_nonwild_patterns = |&: &col: &uint| -> bool {
         m.iter().any(|row| match row.pats[col].node {
             ast::PatWild(_) => false,
             _ => true
diff --git a/src/librustc_trans/trans/basic_block.rs b/src/librustc_trans/trans/basic_block.rs
index 1bd29038fdf..dca106a3897 100644
--- a/src/librustc_trans/trans/basic_block.rs
+++ b/src/librustc_trans/trans/basic_block.rs
@@ -17,7 +17,12 @@ pub struct BasicBlock(pub BasicBlockRef);
 
 impl Copy for BasicBlock {}
 
-pub type Preds<'a> = Map<Value, BasicBlock, Filter<'a, Value, Users>, fn(Value) -> BasicBlock>;
+pub type Preds = Map<
+    Value,
+    BasicBlock,
+    Filter<Value, Users, fn(&Value) -> bool>,
+    fn(Value) -> BasicBlock,
+>;
 
 /// Wrapper for LLVM BasicBlockRef
 impl BasicBlock {
@@ -31,11 +36,12 @@ impl BasicBlock {
         }
     }
 
-    pub fn pred_iter(self) -> Preds<'static> {
+    pub fn pred_iter(self) -> Preds {
+        fn is_a_terminator_inst(user: &Value) -> bool { user.is_a_terminator_inst() }
         fn get_parent(user: Value) -> BasicBlock { user.get_parent().unwrap() }
 
         self.as_value().user_iter()
-            .filter(|user| user.is_a_terminator_inst())
+            .filter(is_a_terminator_inst)
             .map(get_parent)
     }