diff --git a/debugXML.c b/debugXML.c
index df50f66..fcfa57f 100644
--- a/debugXML.c
+++ b/debugXML.c
@@ -7,6 +7,7 @@
  * Daniel Veillard <daniel@veillard.com>
  */
 
+#define IN_LIBXML
 #include "libxml.h"
 #ifdef LIBXML_DEBUG_ENABLED