Remove useless vector accumulation in type_vars_for_defs

Author: aturon

src/librustc/middle/infer/mod.rs

@@ -1025,8 +1025,6 @@ impl<'a, 'tcx> InferCtxt<'a, 'tcx> {
                               substs: &mut Substs<'tcx>,
                               defs: &[ty::TypeParameterDef<'tcx>]) {
 
-        let mut vars = Vec::with_capacity(defs.len());
-
         for def in defs.iter() {
             let default = def.default.map(|default| {
                 type_variable::Default {
@@ -1038,7 +1036,6 @@ impl<'a, 'tcx> InferCtxt<'a, 'tcx> {
 
             let ty_var = self.next_ty_var_with_default(default);
             substs.types.push(space, ty_var);
-            vars.push(ty_var)
         }
     }