remove SupSupConflict, which is now dead code

Author: nikomatsakis

src/librustc/middle/infer/error_reporting.rs

@@ -65,7 +65,6 @@ use super::ValuePairs;
 use super::region_inference::RegionResolutionError;
 use super::region_inference::ConcreteFailure;
 use super::region_inference::SubSupConflict;
-use super::region_inference::SupSupConflict;
 use super::region_inference::GenericBoundFailure;
 use super::region_inference::GenericKind;
 use super::region_inference::ProcessedErrors;
@@ -258,13 +257,6 @@ pub trait ErrorReporting<'tcx> {
                                sup_origin: SubregionOrigin<'tcx>,
                                sup_region: Region);
 
-    fn report_sup_sup_conflict(&self,
-                               var_origin: RegionVariableOrigin,
-                               origin1: SubregionOrigin<'tcx>,
-                               region1: Region,
-                               origin2: SubregionOrigin<'tcx>,
-                               region2: Region);
-
     fn report_processed_errors(&self,
                                var_origin: &[RegionVariableOrigin],
                                trace_origin: &[(TypeTrace<'tcx>, TypeError<'tcx>)],
@@ -313,14 +305,6 @@ impl<'a, 'tcx> ErrorReporting<'tcx> for InferCtxt<'a, 'tcx> {
                                                  sup_origin, sup_r);
                 }
 
-                SupSupConflict(var_origin,
-                               origin1, r1,
-                               origin2, r2) => {
-                    self.report_sup_sup_conflict(var_origin,
-                                                 origin1, r1,
-                                                 origin2, r2);
-                }
-
                 ProcessedErrors(ref var_origins,
                                 ref trace_origins,
                                 ref same_regions) => {
@@ -376,7 +360,6 @@ impl<'a, 'tcx> ErrorReporting<'tcx> for InferCtxt<'a, 'tcx> {
                         None => processed_errors.push((*error).clone()),
                     }
                 }
-                SupSupConflict(..) => processed_errors.push((*error).clone()),
                 _ => ()  // This shouldn't happen
             }
         }
@@ -930,29 +913,6 @@ impl<'a, 'tcx> ErrorReporting<'tcx> for InferCtxt<'a, 'tcx> {
         self.note_region_origin(&sub_origin);
     }
 
-    fn report_sup_sup_conflict(&self,
-                               var_origin: RegionVariableOrigin,
-                               origin1: SubregionOrigin<'tcx>,
-                               region1: Region,
-                               origin2: SubregionOrigin<'tcx>,
-                               region2: Region) {
-        self.report_inference_failure(var_origin);
-
-        self.tcx.note_and_explain_region(
-            "first, the lifetime must be contained by ",
-            region1,
-            "...");
-
-        self.note_region_origin(&origin1);
-
-        self.tcx.note_and_explain_region(
-            "but, the lifetime must also be contained by ",
-            region2,
-            "...");
-
-        self.note_region_origin(&origin2);
-    }
-
     fn report_processed_errors(&self,
                                var_origins: &[RegionVariableOrigin],
                                trace_origins: &[(TypeTrace<'tcx>, TypeError<'tcx>)],

src/librustc/middle/infer/region_inference/mod.rs

@@ -141,15 +141,6 @@ pub enum RegionResolutionError<'tcx> {
                    SubregionOrigin<'tcx>, Region,
                    SubregionOrigin<'tcx>, Region),
 
-    /// `SupSupConflict(v, origin1, r1, origin2, r2)`:
-    ///
-    /// Could not infer a value for `v` because `v <= r1` (due to
-    /// `origin1`) and `v <= r2` (due to `origin2`) and
-    /// `r1` and `r2` have no intersection.
-    SupSupConflict(RegionVariableOrigin,
-                   SubregionOrigin<'tcx>, Region,
-                   SubregionOrigin<'tcx>, Region),
-
     /// For subsets of `ConcreteFailure` and `SubSupConflict`, we can derive
     /// more specific errors message by suggesting to the user where they
     /// should put a lifetime. In those cases we process and put those errors