Remove unused ErrorReporting variant from overflow handling

compiler/rustc_middle/src/traits/mod.rs

@@ -611,9 +611,6 @@ pub enum SelectionError<'tcx> {
     NotConstEvaluatable(NotConstEvaluatable),
     /// Exceeded the recursion depth during type projection.
     Overflow(OverflowError),
-    /// Signaling that an error has already been emitted, to avoid
-    /// multiple errors being shown.
-    ErrorReporting,
     /// Computing an opaque type's hidden type caused an error (e.g. a cycle error).
     /// We can thus not know whether the hidden type implements an auto trait, so
     /// we should not presume anything about it.

compiler/rustc_middle/src/traits/select.rs

@@ -302,7 +302,6 @@ impl EvaluationResult {
 pub enum OverflowError {
     Error(ErrorGuaranteed),
     Canonical,
-    ErrorReporting,
 }
 
 impl From<ErrorGuaranteed> for OverflowError {
@@ -318,7 +317,6 @@ impl<'tcx> From<OverflowError> for SelectionError<'tcx> {
         match overflow_error {
             OverflowError::Error(e) => SelectionError::Overflow(OverflowError::Error(e)),
             OverflowError::Canonical => SelectionError::Overflow(OverflowError::Canonical),
-            OverflowError::ErrorReporting => SelectionError::ErrorReporting,
         }
     }
 }

compiler/rustc_trait_selection/src/traits/error_reporting/type_err_ctxt_ext.rs

@@ -947,9 +947,6 @@ impl<'tcx> TypeErrCtxtExt<'tcx> for TypeErrCtxt<'_, 'tcx> {
             Overflow(_) => {
                 bug!("overflow should be handled before the `report_selection_error` path");
             }
-            SelectionError::ErrorReporting => {
-                bug!("ErrorReporting Overflow should not reach `report_selection_err` call")
-            }
         };
 
         self.note_obligation_cause(&mut err, &obligation);

compiler/rustc_trait_selection/src/traits/query/evaluate_obligation.rs

@@ -116,11 +116,9 @@ impl<'tcx> InferCtxtExt<'tcx> for InferCtxt<'tcx> {
                             r,
                         )
                     }
-                    OverflowError::ErrorReporting => EvaluationResult::EvaluatedToErr,
                     OverflowError::Error(_) => EvaluationResult::EvaluatedToErr,
                 })
             }
-            Err(OverflowError::ErrorReporting) => EvaluationResult::EvaluatedToErr,
             Err(OverflowError::Error(_)) => EvaluationResult::EvaluatedToErr,
         }
     }

compiler/rustc_trait_selection/src/traits/select/mod.rs

@@ -14,9 +14,9 @@ use super::util;
 use super::util::closure_trait_ref_and_return_type;
 use super::wf;
 use super::{
-    ErrorReporting, ImplDerivedObligation, ImplDerivedObligationCause, Normalized, Obligation,
-    ObligationCause, ObligationCauseCode, Overflow, PolyTraitObligation, PredicateObligation,
-    Selection, SelectionError, SelectionResult, TraitQueryMode,
+    ImplDerivedObligation, ImplDerivedObligationCause, Normalized, Obligation, ObligationCause,
+    ObligationCauseCode, Overflow, PolyTraitObligation, PredicateObligation, Selection,
+    SelectionError, SelectionResult, TraitQueryMode,
 };
 
 use crate::infer::{InferCtxt, InferOk, TypeFreshener};
@@ -496,7 +496,6 @@ impl<'cx, 'tcx> SelectionContext<'cx, 'tcx> {
                 }
                 Ok(_) => Ok(None),
                 Err(OverflowError::Canonical) => Err(Overflow(OverflowError::Canonical)),
-                Err(OverflowError::ErrorReporting) => Err(ErrorReporting),
                 Err(OverflowError::Error(e)) => Err(Overflow(OverflowError::Error(e))),
             })
             .flat_map(Result::transpose)
@@ -1233,7 +1232,6 @@ impl<'cx, 'tcx> SelectionContext<'cx, 'tcx> {
             Ok(Some(c)) => self.evaluate_candidate(stack, &c),
             Ok(None) => Ok(EvaluatedToAmbig),
             Err(Overflow(OverflowError::Canonical)) => Err(OverflowError::Canonical),
-            Err(ErrorReporting) => Err(OverflowError::ErrorReporting),
             Err(..) => Ok(EvaluatedToErr),
         }
     }

src/librustdoc/clean/blanket_impl.rs

@@ -81,7 +81,6 @@ impl<'a, 'tcx> BlanketImplFinder<'a, 'tcx> {
                     match infcx.evaluate_obligation(&obligation) {
                         Ok(eval_result) if eval_result.may_apply() => {}
                         Err(traits::OverflowError::Canonical) => {}
-                        Err(traits::OverflowError::ErrorReporting) => {}
                         _ => continue 'blanket_impls,
                     }
                 }