cs: fix iteration on copy of a mutable hash table

Incorrect initialization of the copy's iteration state for a hash
table meant that table sizes larger than 32 looked like tables of only
32 elements when iterating (including when printing).

Closes #3344

pkgs/racket-test-core/tests/racket/hash.rktl

@@ -577,6 +577,27 @@
   (test 1 hash-count ht2)
   (test #t eq? (car (hash-keys ht2)) g))
 
+;; ----------------------------------------
+;; Regression test to make sure all elements are still
+;; reachable by iteration in a copy of a mutable hash table:
+
+(let ([ht (make-hash)])
+  (for ([i 113])
+    (hash-set! ht i 1))
+
+  (define new-ht (hash-copy ht))
+
+  (test (hash-count ht) hash-count new-ht)
+  (test (for/sum ([k (in-hash-keys ht)])
+          k)
+        'sum
+        (for/sum ([k (in-hash-keys new-ht)])
+          k))
+  (test (hash-count ht)
+        'count
+        (for/sum ([v (in-hash-values new-ht)])
+          v)))
+
 ;; ----------------------------------------
 
 (report-errs)

racket/src/cs/rumble/hash.ss

@@ -14,8 +14,8 @@
 (define-record eq-mutable-hash mutable-hash
   ())
 
-(define (create-mutable-hash ht kind) (make-mutable-hash (make-lock kind) #f #f ht))
-(define (create-eq-mutable-hash ht) (make-eq-mutable-hash (make-lock 'eq?) #f #f ht))
+(define (create-mutable-hash ht kind) (make-mutable-hash (make-lock kind) #f #t ht))
+(define (create-eq-mutable-hash ht) (make-eq-mutable-hash (make-lock 'eq?) #f #t ht))
 
 (define (mutable-hash-lock ht) (locked-iterable-hash-lock ht))
 (define (mutable-hash-cells ht) (locked-iterable-hash-cells ht))
@@ -654,7 +654,7 @@
                                  0)
                              32))])
         (let ([len (#%vector-length new-vec)])
-          (when (fx= len (hash-count ht))<
+          (when (fx= len (hash-count ht))
             (set-locked-iterable-hash-retry?! ht #f)))
         (let ([vec (cells-merge vec new-vec)])
           (set-locked-iterable-hash-cells! ht vec)