Function rustc_type_ir::relate::relate_args_with_variances

source ยท 
pub fn relate_args_with_variances<I: Interner, R: TypeRelation<I>>(
    relation: &mut R,
    ty_def_id: I::DefId,
    variances: I::VariancesOf,
    a_arg: I::GenericArgs,
    b_arg: I::GenericArgs,
    fetch_ty_for_diag: bool,
) -> RelateResult<I, I::GenericArgs>