diff --git a/collects/typed-scheme/test.ss b/collects/typed-scheme/test.ss
index 097675c0..c4733b51 100644
--- a/collects/typed-scheme/test.ss
+++ b/collects/typed-scheme/test.ss
@@ -48,4 +48,8 @@
 #{(lambda: ([x : Number]) 1) :: (Integer -> Any)}
 #{(lambda: ([x : Number]) x) :: (Number -> Number)}
 #{(lambda: ([x : Number]) x) :: (Integer -> Any)}
+(define zzz 1)
+(set! zzz 2)
+
+(define-struct: xxx ())
 
diff --git a/collects/typed-scheme/typecheck/tc-expr-unit.ss b/collects/typed-scheme/typecheck/tc-expr-unit.ss
index c1fb45ec..831e0dcd 100644
--- a/collects/typed-scheme/typecheck/tc-expr-unit.ss
+++ b/collects/typed-scheme/typecheck/tc-expr-unit.ss
@@ -298,8 +298,8 @@
        (tc/letrec-values #'((name ...) ...) #'(expr ...) #'body form)]        
       ;; mutation!
       [(set! id val)
-       (match-let* ([(tc-result: id-t) (tc-expr #'id)]
-                    [(tc-result: val-t) (tc-expr #'val)])
+       (match-let* ([(tc-result1: id-t) (tc-expr #'id)]
+                    [(tc-result1: val-t) (tc-expr #'val)])
          (unless (subtype val-t id-t)
            (tc-error/expr "Mutation only allowed with compatible types:~n~a is not a subtype of ~a" val-t id-t))
          (ret -Void))]        
diff --git a/collects/typed-scheme/typecheck/tc-toplevel.ss b/collects/typed-scheme/typecheck/tc-toplevel.ss
index dd771af2..c3295e29 100644
--- a/collects/typed-scheme/typecheck/tc-toplevel.ss
+++ b/collects/typed-scheme/typecheck/tc-toplevel.ss
@@ -114,7 +114,7 @@
                    (begin0 (tc-expr #'expr)
                            (restore-errors!))))
             => (match-lambda 
-                 [(tc-result: t)
+                 [(tc-result1: t)
                   (register-type (car vars) t)
                   (list (make-def-binding (car vars) t))]
                  [t (int-err "~a is not a tc-result" t)])]