diff --git a/compiler/old-rt/vm.lisp b/compiler/old-rt/vm.lisp
index 9108a902e59abad00fef248321ce3e59de42b982..963bce79d916a73c2d7152d6921f80faeb5432b7 100644
--- a/compiler/old-rt/vm.lisp
+++ b/compiler/old-rt/vm.lisp
@@ -125,7 +125,7 @@
 (def-primitive-type list (descriptor-reg))
 
 ;;; Dummy primitive type for catch block TNs.
-(def-primitive-type catch-block (stack) :type nil)
+(def-primitive-type catch-block (catch-block) :type nil)
 
 
 ;;; Primitive-Type-Of  --  Interface