pub fn compute_inherent_assoc_ty_args<'a, 'b, 'tcx>(
    selcx: &'a mut SelectionContext<'b, 'tcx>,
    param_env: ParamEnv<'tcx>,
    alias_ty: AliasTy<'tcx>,
    cause: ObligationCause<'tcx>,
    depth: usize,
    obligations: &mut Vec<PredicateObligation<'tcx>>
) -> GenericArgsRef<'tcx>