rustc_typeck: unbox closures used in let bindings

Author: Jorge Aparicio

src/librustc_typeck/check/vtable.rs

@@ -223,7 +223,7 @@ fn check_object_safety_inner<'tcx>(tcx: &ty::ctxt<'tcx>,
         }
 
         // reason (a) above
-        let check_for_self_ty = |ty| {
+        let check_for_self_ty = |&: ty| {
             if contains_illegal_self_type_reference(tcx, object_trait.def_id(), ty) {
                 Some(format!(
                     "cannot call a method (`{}`) whose type contains \

src/librustc_typeck/variance.rs

@@ -593,7 +593,7 @@ impl<'a, 'tcx> ConstraintContext<'a, 'tcx> {
         // parameter (by inspecting parent of its binding declaration
         // to see if it is introduced by a type or by a fn/impl).
 
-        let check_result = |this:&ConstraintContext| -> bool {
+        let check_result = |&: this:&ConstraintContext| -> bool {
             let tcx = this.terms_cx.tcx;
             let decl_id = this.find_binding_for_lifetime(param_id);
             // Currently only called on lifetimes; double-checking that.