Rollup merge of rust-lang#119337 - mu001999:dead_code/clean, r=WaffleLapkin

Remove dead codes

Detected by rust-lang#118257

Author: matthiaskrgr

compiler/rustc_infer/src/infer/relate/combine.rs

@@ -335,7 +335,7 @@ impl<'tcx> InferCtxt<'tcx> {
         // constants and generic expressions are not yet handled correctly.
         let Generalization { value_may_be_infer: value, needs_wf: _ } = generalize::generalize(
             self,
-            &mut CombineDelegate { infcx: self, span, param_env },
+            &mut CombineDelegate { infcx: self, span },
             ct,
             target_vid,
             ty::Variance::Invariant,
@@ -454,11 +454,7 @@ impl<'infcx, 'tcx> CombineFields<'infcx, 'tcx> {
         // adding constraints like `'x: '?2` and `?1 <: ?3`.)
         let Generalization { value_may_be_infer: b_ty, needs_wf } = generalize::generalize(
             self.infcx,
-            &mut CombineDelegate {
-                infcx: self.infcx,
-                param_env: self.param_env,
-                span: self.trace.span(),
-            },
+            &mut CombineDelegate { infcx: self.infcx, span: self.trace.span() },
             a_ty,
             b_vid,
             ambient_variance,

compiler/rustc_infer/src/infer/relate/generalize.rs

@@ -55,8 +55,6 @@ pub fn generalize<'tcx, D: GeneralizerDelegate<'tcx>, T: Into<Term<'tcx>> + Rela
 /// Abstracts the handling of region vars between HIR and MIR/NLL typechecking
 /// in the generalizer code.
 pub trait GeneralizerDelegate<'tcx> {
-    fn param_env(&self) -> ty::ParamEnv<'tcx>;
-
     fn forbid_inference_vars() -> bool;
 
     fn span(&self) -> Span;
@@ -66,15 +64,10 @@ pub trait GeneralizerDelegate<'tcx> {
 
 pub struct CombineDelegate<'cx, 'tcx> {
     pub infcx: &'cx InferCtxt<'tcx>,
-    pub param_env: ty::ParamEnv<'tcx>,
     pub span: Span,
 }
 
 impl<'tcx> GeneralizerDelegate<'tcx> for CombineDelegate<'_, 'tcx> {
-    fn param_env(&self) -> ty::ParamEnv<'tcx> {
-        self.param_env
-    }
-
     fn forbid_inference_vars() -> bool {
         false
     }
@@ -95,10 +88,6 @@ impl<'tcx, T> GeneralizerDelegate<'tcx> for T
 where
     T: TypeRelatingDelegate<'tcx>,
 {
-    fn param_env(&self) -> ty::ParamEnv<'tcx> {
-        <Self as TypeRelatingDelegate<'tcx>>::param_env(self)
-    }
-
     fn forbid_inference_vars() -> bool {
         <Self as TypeRelatingDelegate<'tcx>>::forbid_inference_vars()
     }