1 files changed, 1 insertions, 1 deletions
diff --git a/eval.cpp b/eval.cpp
index 279f8c4..07ea00e 100644
--- a/eval.cpp
+++ b/eval.cpp
@@ -26,7 +26,7 @@ void Evaluator::add_builtin_routines() {
 }
 
 Evaluator::Evaluator() {
-    envt = new Environment();       // Top-level Environment
+    envt = new Environment(NULL);       // Top-level Environment
     add_builtin_routines();
 }