diff --git a/bin/tpc.php b/bin/tpc.php
index f0fd0bff..6bfdb948 100755
--- a/bin/tpc.php
+++ b/bin/tpc.php
@@ -5,5 +5,5 @@ require __DIR__ . '/../src/polyfills.php';
 require __DIR__ . '/../src/gen_stub.php';
 require __DIR__ . '/../src/compiler.php';
 
-define('TYPEPHP_PHP_SCRIPT_ENTRY', true);
+const TYPEPHP_PHP_SCRIPT_ENTRY = true;
 main($argc, $argv);