diff --git a/runtime.h b/runtime.h
index 311ec857..a99a9fc1 100644
--- a/runtime.h
+++ b/runtime.h
@@ -1476,6 +1476,20 @@ static object apply(object cont, object func, object args){
       }
       
       break;
+    // TODO: if #define CYC_EVAL
+// TODO: also, this only works if the generated code knows to call apply, want to do this,
+//       but again only if CYC_EVAL is defined:
+//#define funcall2(cfn,a1,a2) if (type_of(cfn) == cons_tag || prim(cfn)) { Cyc_apply(1, (closure)a1, cfn,a2); } else { ((cfn)->fn)(2,cfn,a1,a2);}
+    case cons_tag:
+      if (!nullp(func) && eq(quote_Cyc_191procedure, car(func))) {
+          printf("TODO: apply compound proc\n");
+          exit(1);
+      } else {
+          printf("Unable to evaluate list\n");
+          exit(1);
+      }
+    // TODO: #endif
+      
     default:
       printf("Invalid object type %ld\n", type_of(func));
       exit(1);