diff --git a/src/librustc/middle/typeck/check/mod.rs b/src/librustc/middle/typeck/check/mod.rs
index 98db885ba4227..00ebca5abc147 100644
--- a/src/librustc/middle/typeck/check/mod.rs
+++ b/src/librustc/middle/typeck/check/mod.rs
@@ -686,7 +686,7 @@ impl FnCtxt {
                     result::Err(RegionError {
                         msg: {
                             fmt!("named region `%s` not in scope here",
-                                 bound_region_to_str(self.tcx(), br))
+                                 bound_region_ptr_to_str(self.tcx(), br))
                         },
                         replacement: {
                             self.infcx().next_region_var(
diff --git a/src/librustc/middle/typeck/infer/error_reporting.rs b/src/librustc/middle/typeck/infer/error_reporting.rs
index 7217f29794746..e533f019b4692 100644
--- a/src/librustc/middle/typeck/infer/error_reporting.rs
+++ b/src/librustc/middle/typeck/infer/error_reporting.rs
@@ -59,7 +59,7 @@ time of error detection.
 
 */
 
-use core::prelude::*;
+use std::prelude::*;
 use middle::ty;
 use middle::ty::Region;
 use middle::typeck::infer;
@@ -80,10 +80,46 @@ use syntax::opt_vec::OptVec;
 use util::ppaux::UserString;
 use util::ppaux::note_and_explain_region;
 
-impl InferCtxt {
+pub trait ErrorReporting {
+    pub fn report_region_errors(@mut self,
+                                errors: &OptVec<RegionResolutionError>);
+
+    pub fn report_and_explain_type_error(@mut self,
+                                         trace: TypeTrace,
+                                         terr: &ty::type_err);
+
+    fn values_str(@mut self, values: &ValuePairs) -> Option<~str>;
+
+    fn expected_found_str<T:UserString+Resolvable>(
+        @mut self,
+        exp_found: &ty::expected_found<T>)
+        -> Option<~str>;
+
+    fn report_concrete_failure(@mut self,
+                               origin: SubregionOrigin,
+                               sub: Region,
+                               sup: Region);
+
+    fn report_sub_sup_conflict(@mut self,
+                               var_origin: RegionVariableOrigin,
+                               sub_origin: SubregionOrigin,
+                               sub_region: Region,
+                               sup_origin: SubregionOrigin,
+                               sup_region: Region);
+
+    fn report_sup_sup_conflict(@mut self,
+                               var_origin: RegionVariableOrigin,
+                               origin1: SubregionOrigin,
+                               region1: Region,
+                               origin2: SubregionOrigin,
+                               region2: Region);
+}
+
+
+impl ErrorReporting for InferCtxt {
     pub fn report_region_errors(@mut self,
                                 errors: &OptVec<RegionResolutionError>) {
-        for errors.each |error| {
+        for errors.iter().advance |error| {
             match *error {
                 ConcreteFailure(origin, sub, sup) => {
                     self.report_concrete_failure(origin, sub, sup);
diff --git a/src/librustc/middle/typeck/infer/mod.rs b/src/librustc/middle/typeck/infer/mod.rs
index bddd0276c6abe..3360edc6a4678 100644
--- a/src/librustc/middle/typeck/infer/mod.rs
+++ b/src/librustc/middle/typeck/infer/mod.rs
@@ -31,6 +31,7 @@ use middle::typeck::infer::sub::Sub;
 use middle::typeck::infer::lub::Lub;
 use middle::typeck::infer::to_str::InferStr;
 use middle::typeck::infer::unify::{ValsAndBindings, Root};
+use middle::typeck::infer::error_reporting::ErrorReporting;
 use middle::typeck::isr_alist;
 use util::common::indent;
 use util::ppaux::{bound_region_to_str, ty_to_str, trait_ref_to_str, Repr,
diff --git a/src/librustc/middle/typeck/infer/region_inference/mod.rs b/src/librustc/middle/typeck/infer/region_inference/mod.rs
index b474b95d0fec2..96cb5d3c747c3 100644
--- a/src/librustc/middle/typeck/infer/region_inference/mod.rs
+++ b/src/librustc/middle/typeck/infer/region_inference/mod.rs
@@ -36,7 +36,8 @@ mod doc;
 enum Constraint {
     ConstrainVarSubVar(RegionVid, RegionVid),
     ConstrainRegSubVar(Region, RegionVid),
-    ConstrainVarSubReg(RegionVid, Region)
+    ConstrainVarSubReg(RegionVid, Region),
+    ConstrainRegSubReg(Region, Region),
 }
 
 #[deriving(Eq, IterBytes)]
@@ -454,7 +455,7 @@ impl RegionVarBindings {
         {
             let mut result_set = result_set;
             if r == r1 { // Clearly, this is potentially inefficient.
-                if !result_set.iter().any_(|x| x == r2) {
+                if !result_set.iter().any_(|x| *x == r2) {
                     result_set.push(r2);
                 }
             }
diff --git a/src/librustc/util/ppaux.rs b/src/librustc/util/ppaux.rs
index 1a0cdd6fa64fa..6289407114534 100644
--- a/src/librustc/util/ppaux.rs
+++ b/src/librustc/util/ppaux.rs
@@ -610,7 +610,7 @@ impl Repr for @ast::pat {
 
 impl Repr for ty::bound_region {
     fn repr(&self, tcx: ctxt) -> ~str {
-        bound_region_to_str(tcx, *self)
+        bound_region_ptr_to_str(tcx, *self)
     }
 }
 
diff --git a/src/test/compile-fail/regions-bounds.rs b/src/test/compile-fail/regions-bounds.rs
index f92ea7f18cec4..ab2ac6cc0e5b9 100644
--- a/src/test/compile-fail/regions-bounds.rs
+++ b/src/test/compile-fail/regions-bounds.rs
@@ -16,12 +16,12 @@ struct an_enum<'self>(&'self int);
 struct a_class<'self> { x:&'self int }
 
 fn a_fn1<'a,'b>(e: an_enum<'a>) -> an_enum<'b> {
-    return e; //~ ERROR mismatched types: expected `an_enum<'b> ` but found `an_enum<'a> `
+    return e; //~ ERROR mismatched types: expected `an_enum<'b>` but found `an_enum<'a>`
     //~^ ERROR cannot infer an appropriate lifetime
 }
 
 fn a_fn3<'a,'b>(e: a_class<'a>) -> a_class<'b> {
-    return e; //~ ERROR mismatched types: expected `a_class<'b> ` but found `a_class<'a> `
+    return e; //~ ERROR mismatched types: expected `a_class<'b>` but found `a_class<'a>`
     //~^ ERROR cannot infer an appropriate lifetime
 }