diff --git a/collects/tests/mzscheme/basic.ss b/collects/tests/mzscheme/basic.ss
index b71c80a31b..75cb36316c 100644
--- a/collects/tests/mzscheme/basic.ss
+++ b/collects/tests/mzscheme/basic.ss
@@ -1991,7 +1991,7 @@
 (arity-test hash-table-for-each 2 2)
 (arity-test hash-table? 1 3)
 
-;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
+;; ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
 ;; Misc
 
 (test #t string? (version))
@@ -2013,6 +2013,30 @@
 (arity-test system-library-subpath 0 1)
 (arity-test current-command-line-arguments 0 1)
 
+;; ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
+;; procedure-closure-contents-eq?
+
+(for-each
+ (lambda (jit?)
+   (parameterize ([eval-jit-enabled jit?])
+     (let ([f #f])
+       (set! f (eval '(lambda (x) (lambda () x))))
+       ((f 'c)) ; forced JIT compilation
+       (test #t procedure-closure-contents-eq? (f 'a) (f 'a))
+       (test #f procedure-closure-contents-eq? (f 'a) (f 'b))
+       (set! f (eval '(case-lambda
+		       [(x) (lambda () 12)]
+		       [(x y) (lambda () (list x y))])))
+       ((f 'c)) ; forces JIT compilation
+       ((f 'c 'd)) ; forces JIT compilation
+       (test #t procedure-closure-contents-eq? (f 'a) (f 'a))
+       (test #t procedure-closure-contents-eq? (f 'a 'b) (f 'a 'b))
+       (test #f procedure-closure-contents-eq? (f 'a 'b) (f 'c 'b)))))
+ '(#t #f))
+(test #t procedure-closure-contents-eq? add1 add1)
+
+;; ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
+
 (report-errs)
 
 "last item in file"
diff --git a/collects/tests/mzscheme/optimize.ss b/collects/tests/mzscheme/optimize.ss
index e8d0d50915..d07c001c60 100644
--- a/collects/tests/mzscheme/optimize.ss
+++ b/collects/tests/mzscheme/optimize.ss
@@ -333,4 +333,17 @@
 (test-comp '(let ([f (lambda (x) x)]) f)
 	   (syntax-property (datum->syntax-object #f '(lambda (x) x)) 'inferred-name 'f))
 
+(test-comp '(letrec ([f (lambda (x) x)])
+	      (f 10)
+	      f)
+	   '(letrec ([f (lambda (x) x)])
+	      f))
+(test-comp '(let ([f (lambda (x) x)])
+	      (f 10))
+	   10)
+(test-comp '(let ([f (lambda (x) (add1 x))]
+		  [y 10])
+	      (f y))
+	   '11)
+
 (report-errs)
diff --git a/collects/tests/mzscheme/syntax.ss b/collects/tests/mzscheme/syntax.ss
index 6bb7d1855d..bddcc0270d 100644
--- a/collects/tests/mzscheme/syntax.ss
+++ b/collects/tests/mzscheme/syntax.ss
@@ -1081,6 +1081,20 @@
     (g))
   (test 16 values val))
 
+;; Function-inline test where (h (g v 10)) involves two inlines:
+(letrec ([f (lambda (x) (h (g v 10)))]
+	 [h (lambda (x) (list x x))]
+	 [g (lambda (a b) a)]
+	 [v (list 'hello)]
+	 [w (list 'no!)]) 
+  (test '((hello) (hello)) f 10))
+
+;; Inlining introduces a let binding that is immediately dropped:
+(test '(1 . 2)
+      (let ([x (cons 1 2)]) (let ([f (lambda (x) x)]) (f (lambda (y) x))))
+      10)
+
 ;; ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
 
 (report-errs)
+