don't use NDEBUG
diff --git a/Include/object.h b/Include/object.h
index 5727747..a79d1f7 100644
--- a/Include/object.h
+++ b/Include/object.h
@@ -28,10 +28,6 @@
 
 ******************************************************************/
 
-#ifndef DEBUG
-#define NDEBUG
-#endif
-
 /* Object and type object interface */
 
 /*
@@ -81,7 +77,7 @@
 123456789-123456789-123456789-123456789-123456789-123456789-123456789-12
 */
 
-#ifndef NDEBUG
+#ifdef DEBUG
 
 /* Turn on heavy reference debugging */
 #define Py_TRACE_REFS
@@ -89,7 +85,7 @@
 /* Turn on reference counting */
 #define Py_REF_DEBUG
 
-#endif /* NDEBUG */
+#endif /* DEBUG */
 
 #ifdef Py_TRACE_REFS
 #define PyObject_HEAD \