Remove unused code from rustc_infer

compiler/rustc_infer/src/infer/mod.rs

@@ -113,13 +113,6 @@ impl Default for RegionckMode {
 }
 
 impl RegionckMode {
-    pub fn suppressed(self) -> bool {
-        match self {
-            Self::Solve => false,
-            Self::Erase { suppress_errors } => suppress_errors,
-        }
-    }
-
     /// Indicates that the MIR borrowck will repeat these region
     /// checks, so we should ignore errors if NLL is (unconditionally)
     /// enabled.
@@ -420,15 +413,6 @@ pub enum SubregionOrigin<'tcx> {
 #[cfg(target_arch = "x86_64")]
 static_assert_size!(SubregionOrigin<'_>, 32);
 
-/// Places that type/region parameters can appear.
-#[derive(Clone, Copy, Debug)]
-pub enum ParameterOrigin {
-    Path,               // foo::bar
-    MethodCall,         // foo.bar() <-- parameters on impl providing bar()
-    OverloadedOperator, // a + b when overloaded
-    OverloadedDeref,    // *a when overloaded
-}
-
 /// Times when we replace late-bound regions with variables:
 #[derive(Clone, Copy, Debug)]
 pub enum LateBoundRegionConversionTime {
@@ -508,21 +492,6 @@ pub enum NLLRegionVariableOrigin {
     },
 }
 
-impl NLLRegionVariableOrigin {
-    pub fn is_universal(self) -> bool {
-        match self {
-            NLLRegionVariableOrigin::FreeRegion => true,
-            NLLRegionVariableOrigin::Placeholder(..) => true,
-            NLLRegionVariableOrigin::Existential { .. } => false,
-            NLLRegionVariableOrigin::RootEmptyRegion => false,
-        }
-    }
-
-    pub fn is_existential(self) -> bool {
-        !self.is_universal()
-    }
-}
-
 // FIXME(eddyb) investigate overlap between this and `TyOrConstInferVar`.
 #[derive(Copy, Clone, Debug)]
 pub enum FixupError<'tcx> {

compiler/rustc_infer/src/infer/nll_relate/mod.rs

@@ -28,7 +28,6 @@ use rustc_data_structures::fx::FxHashMap;
 use rustc_middle::ty::error::TypeError;
 use rustc_middle::ty::fold::{TypeFoldable, TypeVisitor};
 use rustc_middle::ty::relate::{self, Relate, RelateResult, TypeRelation};
-use rustc_middle::ty::subst::GenericArg;
 use rustc_middle::ty::{self, InferConst, Ty, TyCtxt};
 use std::fmt::Debug;
 
@@ -119,12 +118,6 @@ pub trait TypeRelatingDelegate<'tcx> {
     fn forbid_inference_vars() -> bool;
 }
 
-#[derive(Clone, Debug)]
-struct ScopesAndKind<'tcx> {
-    scopes: Vec<BoundRegionScope<'tcx>>,
-    kind: GenericArg<'tcx>,
-}
-
 #[derive(Clone, Debug, Default)]
 struct BoundRegionScope<'tcx> {
     map: FxHashMap<ty::BoundRegion, ty::Region<'tcx>>,

compiler/rustc_infer/src/traits/mod.rs

@@ -59,9 +59,7 @@ pub type TraitObligation<'tcx> = Obligation<'tcx, ty::PolyTraitPredicate<'tcx>>;
 #[cfg(target_arch = "x86_64")]
 static_assert_size!(PredicateObligation<'_>, 32);
 
-pub type Obligations<'tcx, O> = Vec<Obligation<'tcx, O>>;
 pub type PredicateObligations<'tcx> = Vec<PredicateObligation<'tcx>>;
-pub type TraitObligations<'tcx> = Vec<TraitObligation<'tcx>>;
 
 pub type Selection<'tcx> = ImplSource<'tcx, PredicateObligation<'tcx>>;