Function rustc_trait_selection::traits::error_reporting::suggestions::point_at_assoc_type_restriction

fn point_at_assoc_type_restriction<G: EmissionGuarantee>(
    tcx: TyCtxt<'_>,
    err: &mut Diag<'_, G>,
    self_ty_str: &str,
    trait_name: &str,
    predicate: Predicate<'_>,
    generics: &Generics<'_>,
    data: &ImplDerivedCause<'_>
)

On impl evaluation cycles, look for Self::AssocTy restrictions in where clauses, explain they are not allowed and if possible suggest alternatives.