diff --git a/collects/lazy/lazy.rkt b/collects/lazy/lazy.rkt
index e302b9a034..60ed30c82a 100644
--- a/collects/lazy/lazy.rkt
+++ b/collects/lazy/lazy.rkt
@@ -365,14 +365,22 @@
       (or (null? xs)
           (let loop ([x (car xs)] [xs (cdr xs)])
             (if (null? xs) x (and (! x) (loop (car xs) (cdr xs))))))))
-  (defsubst (~and x ...) (hidden-~ (and (hidden-! x) ...)) ~and *and)
+  (define-syntax !and
+    (syntax-rules ()
+      [(_) (and)]
+      [(_ x ... y) (and (hidden-! x) ... y)]))
+  (defsubst (~and x ...) (hidden-~ (!and x ...)) ~and *and)
 
   (define* (*or . xs)
     (let ([xs (!list xs)])
       (and (pair? xs)
            (let loop ([x (car xs)] [xs (cdr xs)])
              (if (null? xs) x (or (! x) (loop (car xs) (cdr xs))))))))
-  (defsubst (~or x ...) (hidden-~ (or (hidden-! x) ...)) ~or *or)
+  (define-syntax !or
+    (syntax-rules ()
+      [(_) (or)]
+      [(_ x ... y) (or (hidden-! x) ... y)]))
+  (defsubst (~or x ...) (hidden-~ (!or x ...)) ~or *or)
 
   ;; --------------------------------------------------------------------------
   ;; Special forms that are still special forms since they use ~begin
diff --git a/collects/tests/lazy/main.rkt b/collects/tests/lazy/main.rkt
index d83898e135..5229ab30bd 100644
--- a/collects/tests/lazy/main.rkt
+++ b/collects/tests/lazy/main.rkt
@@ -1,7 +1,9 @@
 #lang racket/base
 
-(require tests/eli-tester "promise.rkt" "forcers.rkt" "lang.rkt")
+(require tests/eli-tester "promise.rkt" "forcers.rkt" "lang.rkt" "space.rkt")
 
 (test do (promise-tests)
       do (forcer-tests)
-      do (lang-tests))
+      do (lang-tests)
+      do (space-tests))
+
diff --git a/collects/tests/lazy/space.rkt b/collects/tests/lazy/space.rkt
new file mode 100644
index 0000000000..7a2f56ec1e
--- /dev/null
+++ b/collects/tests/lazy/space.rkt
@@ -0,0 +1,46 @@
+#lang racket/base
+
+(require tests/eli-tester)
+
+;; tests for space safety, especially for `or' and `and'
+
+(define (space-tests)
+  (define (one-test first-class?)
+    (collect-garbage)
+    (define mem (current-memory-use))
+    (define t
+      (thread 
+       (lambda () 
+         (parameterize ([current-namespace (make-base-namespace)])
+           (eval
+            `(module loop lazy
+               (let ()
+                 (define (list-from n)
+                   (if (= n 500000)
+                       empty
+                       (cons n (list-from (add1 n)))))
+                 ,@(if first-class?
+                       `((define my-or or)
+                         (define my-and and))
+                       '())
+                 (define (has-negative? l)
+                   (,(if first-class? 'my-and 'and)
+                    (pair? l)
+                    (,(if first-class? 'my-or 'or)
+                     (negative? (car l))
+                     (has-negative? (rest l)))))
+                 (! (has-negative? (list-from 0))))))
+           (eval `(require 'loop))))))
+    (thread (lambda () (let loop ()
+                         (sleep 0.2)
+                         (unless ((current-memory-use) . < . (* 10 mem))
+                           (eprintf "too much memory!")
+                           (kill-thread t))
+                         (when (thread-running? t)
+                           (loop)))))
+    (sync t)
+    (void))
+  (one-test #f)
+  (one-test #t))
+     
+(provide space-tests)