diff --git a/pkgs/racket-test-core/tests/racket/set.rktl b/pkgs/racket-test-core/tests/racket/set.rktl
index 99013eeaeb..9206cb0526 100644
--- a/pkgs/racket-test-core/tests/racket/set.rktl
+++ b/pkgs/racket-test-core/tests/racket/set.rktl
@@ -139,6 +139,9 @@
       'set-symmetric-difference/list
       '(1 3))
 
+(test #t equal? (set) (let ([a (set 1 2 3)]) (set-symmetric-difference a a)))
+(test #t equal? (set) (let ([a (set 1 2 3)] [b (set 1 2 3)]) (set-symmetric-difference a b)))
+
 (let ([s (set 1 2 3)])
   (test #t equal? s (set-add (set-add (set-add (set) 1) 2) 3))
   (test #t equal? (seteq 1 2 3) (seteq 1 2 3))
diff --git a/racket/collects/racket/private/set-types.rkt b/racket/collects/racket/private/set-types.rkt
index 3cac666e70..bc22c1c6a3 100644
--- a/racket/collects/racket/private/set-types.rkt
+++ b/racket/collects/racket/private/set-types.rkt
@@ -186,8 +186,7 @@
    s
    (for/fold
        ([table (custom-set-table largest-immutable)])
-       ([s2 (in-list (cons s sets))]
-        #:unless (eq? s2 largest-immutable))
+       ([s2 (in-list (remove largest-immutable (cons s sets)))])
      (for/fold ([table table]) ([x (in-hash-keys (custom-set-table s2))])
        (if (hash-ref table x #f)
            (hash-remove table x)