Remove default visitor impl in region constraint generation

compiler/rustc_borrowck/src/constraint_generation.rs

@@ -4,8 +4,8 @@ use rustc_infer::infer::InferCtxt;
 use rustc_middle::mir::visit::TyContext;
 use rustc_middle::mir::visit::Visitor;
 use rustc_middle::mir::{
-    BasicBlock, BasicBlockData, Body, Local, Location, Place, PlaceRef, ProjectionElem, Rvalue,
-    SourceInfo, Statement, StatementKind, Terminator, TerminatorKind, UserTypeProjection,
+    Body, Local, Location, Place, PlaceRef, ProjectionElem, Rvalue, SourceInfo, Statement,
+    StatementKind, Terminator, TerminatorKind, UserTypeProjection,
 };
 use rustc_middle::ty::subst::SubstsRef;
 use rustc_middle::ty::visit::TypeVisitable;
@@ -49,10 +49,6 @@ struct ConstraintGeneration<'cg, 'tcx> {
 }
 
 impl<'cg, 'tcx> Visitor<'tcx> for ConstraintGeneration<'cg, 'tcx> {
-    fn visit_basic_block_data(&mut self, bb: BasicBlock, data: &BasicBlockData<'tcx>) {
-        self.super_basic_block_data(bb, data);
-    }
-
     /// We sometimes have `substs` within an rvalue, or within a
     /// call. Make them live at the location where they appear.
     fn visit_substs(&mut self, substs: &SubstsRef<'tcx>, location: Location) {