Rollup merge of #135875 - BoxyUwU:enter_forall_no_copy, r=lcnr

Remove `Copy` bound from `enter_forall`

idk why we ever required this, `TypeFoldable` implies `Clone`

Author: matthiaskrgr

compiler/rustc_infer/src/infer/context.rs

@@ -114,7 +114,7 @@ impl<'tcx> rustc_type_ir::InferCtxtLike for InferCtxt<'tcx> {
         )
     }
 
-    fn enter_forall<T: TypeFoldable<TyCtxt<'tcx>> + Copy, U>(
+    fn enter_forall<T: TypeFoldable<TyCtxt<'tcx>>, U>(
         &self,
         value: ty::Binder<'tcx, T>,
         f: impl FnOnce(T) -> U,

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

@@ -24,9 +24,9 @@ impl<'tcx> InferCtxt<'tcx> {
     #[instrument(level = "debug", skip(self), ret)]
     pub fn enter_forall_and_leak_universe<T>(&self, binder: ty::Binder<'tcx, T>) -> T
     where
-        T: TypeFoldable<TyCtxt<'tcx>> + Copy,
+        T: TypeFoldable<TyCtxt<'tcx>>,
     {
-        if let Some(inner) = binder.no_bound_vars() {
+        if let Some(inner) = binder.clone().no_bound_vars() {
             return inner;
         }
 
@@ -71,7 +71,7 @@ impl<'tcx> InferCtxt<'tcx> {
     #[instrument(level = "debug", skip(self, f))]
     pub fn enter_forall<T, U>(&self, forall: ty::Binder<'tcx, T>, f: impl FnOnce(T) -> U) -> U
     where
-        T: TypeFoldable<TyCtxt<'tcx>> + Copy,
+        T: TypeFoldable<TyCtxt<'tcx>>,
     {
         // FIXME: currently we do nothing to prevent placeholders with the new universe being
         // used after exiting `f`. For example region subtyping can result in outlives constraints