From f0e9bd9099e729eb73b4483795d0057e963c8eac Mon Sep 17 00:00:00 2001
From: Flavio Percoco <flaper87@gmail.com>
Date: Sat, 7 Feb 2015 14:46:08 +0100
Subject: [PATCH] address nits

---
 src/librustc/middle/traits/mod.rs  | 3 +++
 src/librustc/middle/traits/util.rs | 6 +++---
 2 files changed, 6 insertions(+), 3 deletions(-)

diff --git a/src/librustc/middle/traits/mod.rs b/src/librustc/middle/traits/mod.rs
index c400dd5a78a5..8b836fd322e3 100644
--- a/src/librustc/middle/traits/mod.rs
+++ b/src/librustc/middle/traits/mod.rs
@@ -222,6 +222,9 @@ pub enum Vtable<'tcx, N> {
     VtableImpl(VtableImplData<'tcx, N>),
 
     /// Vtable for default trait implementations
+    /// This carries the information and nested obligations with regards
+    /// to a default implementation for a trait `Trait`. The nested obligations
+    /// ensure the trait implementation holds for all the constituent types.
     VtableDefaultImpl(VtableDefaultImplData<N>),
 
     /// Successful resolution to an obligation provided by the caller
diff --git a/src/librustc/middle/traits/util.rs b/src/librustc/middle/traits/util.rs
index 0308604aa8be..9b462e6be60d 100644
--- a/src/librustc/middle/traits/util.rs
+++ b/src/librustc/middle/traits/util.rs
@@ -323,8 +323,8 @@ pub fn trait_ref_for_builtin_bound<'tcx>(
     }
 }
 
+
 pub fn predicate_for_trait_ref<'tcx>(
-    tcx: &ty::ctxt<'tcx>,
     cause: ObligationCause<'tcx>,
     trait_ref: Rc<ty::TraitRef<'tcx>>,
     recursion_depth: uint)
@@ -349,7 +349,7 @@ pub fn predicate_for_default_trait_impl<'tcx>(
         def_id: trait_def_id,
         substs: tcx.mk_substs(Substs::empty().with_self_ty(param_ty))
     });
-    predicate_for_trait_ref(tcx, cause, trait_ref, recursion_depth)
+    predicate_for_trait_ref(cause, trait_ref, recursion_depth)
 }
 
 pub fn predicate_for_builtin_bound<'tcx>(
@@ -361,7 +361,7 @@ pub fn predicate_for_builtin_bound<'tcx>(
     -> Result<PredicateObligation<'tcx>, ErrorReported>
 {
     let trait_ref = try!(trait_ref_for_builtin_bound(tcx, builtin_bound, param_ty));
-    predicate_for_trait_ref(tcx, cause, trait_ref, recursion_depth)
+    predicate_for_trait_ref(cause, trait_ref, recursion_depth)
 }
 
 /// Cast a trait reference into a reference to one of its super