bug#48368: reduced test case

[Andy Wingo]

Test case:

  (define (f a b)
    (let ((c (if (and (eq? a 'foo)
                      (eq? b 'bar))
                 'ERROR
                 a)))
      (pk c)))

If you run as (f 'not-foo 'bar), you get 'ERROR.  Yeeps!