Eliminate DefiningAnchor now that is just a single-variant enum

compiler/rustc_middle/src/traits/mod.rs

@@ -12,8 +12,8 @@ pub mod util;
 use crate::infer::canonical::Canonical;
 use crate::mir::ConstraintCategory;
 use crate::ty::abstract_const::NotConstEvaluatable;
+use crate::ty::GenericArgsRef;
 use crate::ty::{self, AdtKind, Ty};
-use crate::ty::{GenericArgsRef, TyCtxt};
 
 use rustc_data_structures::sync::Lrc;
 use rustc_errors::{Applicability, Diag, EmissionGuarantee};
@@ -997,32 +997,3 @@ pub enum CodegenObligationError {
     Unimplemented,
     FulfillmentError,
 }
-
-/// Defines the treatment of opaque types in a given inference context.
-///
-/// This affects both what opaques are allowed to be defined, but also whether
-/// opaques are replaced with inference vars eagerly in the old solver (e.g.
-/// in projection, and in the signature during function type-checking).
-#[derive(Debug, PartialEq, Eq, Clone, Copy, Hash, HashStable, TypeFoldable, TypeVisitable)]
-#[derive(TyEncodable, TyDecodable)]
-pub enum DefiningAnchor<'tcx> {
-    /// Define opaques which are in-scope of the current item being analyzed.
-    /// Also, eagerly replace these opaque types in `replace_opaque_types_with_inference_vars`.
-    ///
-    /// If the list is empty, do not allow any opaques to be defined. This is used to catch type mismatch
-    /// errors when handling opaque types, and also should be used when we would
-    /// otherwise reveal opaques (such as [`Reveal::All`] reveal mode).
-    Bind(&'tcx ty::List<LocalDefId>),
-}
-
-impl Default for DefiningAnchor<'_> {
-    fn default() -> Self {
-        Self::Bind(ty::List::empty())
-    }
-}
-
-impl<'tcx> DefiningAnchor<'tcx> {
-    pub fn bind(tcx: TyCtxt<'tcx>, item: LocalDefId) -> Self {
-        Self::Bind(tcx.opaque_types_defined_by(item))
-    }
-}