(module
  (type (sub (struct (field (mut i32)))))
  (func
    (param)
    (result (ref eq))
    (local (ref eq) (ref eq) (ref eq) (ref eq) (ref eq))
    (i32.const 0)
    ref.i31
    (if
      (result i32)
      (then (i32.const 777) ref.i31)
      (else (i32.const 555) ref.i31)))
  (export "main" (func 0)))