diff --git a/collects/tests/plai/gc2/bad-collectors/no-collection-collector.rkt b/collects/tests/plai/gc2/bad-collectors/no-collection-collector.rkt
index 21d08d8302..8ff0f06325 100644
--- a/collects/tests/plai/gc2/bad-collectors/no-collection-collector.rkt
+++ b/collects/tests/plai/gc2/bad-collectors/no-collection-collector.rkt
@@ -13,6 +13,10 @@
 (define (gc:cons? loc) #f)
 (define (gc:set-first! pr new) (void))
 (define (gc:set-rest! pr new) (void))
+(define (gc:closure code-ptr env) 0)
+(define (gc:closure-code-ptr ptr) #f)
+(define (gc:closure-env-ref ptr i) 0)
+(define (gc:closure? ptr) #f)
 
 (with-heap (vector 1 2 3)
   (test (gc:deref 0) #f))