diff --git a/lib/compress.js b/lib/compress.js
index 503d3c9c..8df2a3ba 100644
--- a/lib/compress.js
+++ b/lib/compress.js
@@ -260,10 +260,8 @@ merge(Compressor.prototype, {
             }
         });
         var tw = new TreeWalker(function(node, descend){
-            if (!(node instanceof AST_Directive || node instanceof AST_Constant)) {
-                node._squeezed = false;
-                node._optimized = false;
-            }
+            node._squeezed = false;
+            node._optimized = false;
             if (reduce_vars) {
                 if (node instanceof AST_Toplevel) node.globals.each(reset_def);
                 if (node instanceof AST_Scope) node.variables.each(reset_def);