Function rustc_query_impl::make_query::super_predicates_that_define_assoc_type

pub fn super_predicates_that_define_assoc_type<'tcx>(
    tcx: QueryCtxt<'tcx>, 
    key: super_predicates_that_define_assoc_type<'tcx>
) -> QueryStackFrame

The Option<Ident> is the name of an associated type. If it is None, then this query returns the full set of predicates. If Some<Ident>, then the query returns only the subset of super-predicates that reference traits that define the given associated type. This is used to avoid cycles in resolving types like T::Item.