diff --git a/src/librustc/traits/specialize/mod.rs b/src/librustc/traits/specialize/mod.rs
index 6a27558b0b77..24cafa7f7253 100644
--- a/src/librustc/traits/specialize/mod.rs
+++ b/src/librustc/traits/specialize/mod.rs
@@ -25,7 +25,7 @@ use hir::def_id::DefId;
 use infer::{InferCtxt, TypeOrigin};
 use middle::region;
 use ty::subst::{Subst, Substs};
-use traits::{self, Reveal, ObligationCause, Normalized};
+use traits::{self, Reveal, ObligationCause};
 use ty::{self, TyCtxt, TypeFoldable};
 use syntax_pos::DUMMY_SP;
 
@@ -187,21 +187,16 @@ pub fn specializes<'a, 'tcx>(tcx: TyCtxt<'a, 'tcx, 'tcx>,
                              .subst(tcx, &penv.free_substs);
 
     // Create a infcx, taking the predicates of impl1 as assumptions:
-    let result = tcx.infer_ctxt(None, Some(penv), Reveal::ExactMatch).enter(|mut infcx| {
-        // Normalize the trait reference, adding any obligations
-        // that arise into the impl1 assumptions.
-        let Normalized { value: impl1_trait_ref, obligations: normalization_obligations } = {
-            let selcx = &mut SelectionContext::new(&infcx);
-            traits::normalize(selcx, ObligationCause::dummy(), &impl1_trait_ref)
-        };
-        infcx.parameter_environment.caller_bounds.extend(normalization_obligations.into_iter().map(|o| {
-            match tcx.lift_to_global(&o.predicate) {
-                Some(predicate) => predicate,
-                None => {
-                    bug!("specializes: obligation `{:?}` has inference types/regions", o);
+    let result = tcx.infer_ctxt(None, Some(penv), Reveal::ExactMatch).enter(|infcx| {
+        // Normalize the trait reference. The WF rules ought to ensure
+        // that this always succeeds.
+        let impl1_trait_ref =
+            match traits::fully_normalize(&infcx, ObligationCause::dummy(), &impl1_trait_ref) {
+                Ok(impl1_trait_ref) => impl1_trait_ref,
+                Err(err) => {
+                    bug!("failed to fully normalize {:?}: {:?}", impl1_trait_ref, err);
                 }
-            }
-        }));
+            };
 
         // Attempt to prove that impl2 applies, given all of the above.
         fulfill_implication(&infcx, impl1_trait_ref, impl2_def_id).is_ok()