diff --git a/lib/file.c b/lib/file.c
index 6121e1e57..233f02472 100644
--- a/lib/file.c
+++ b/lib/file.c
@@ -103,6 +103,10 @@
 #define _MPRINTF_REPLACE /* use our functions only */
 #include <curl/mprintf.h>
 
+/* The last #include file should be: */
+#ifdef MALLOCDEBUG
+#include "memdebug.h"
+#endif
 
 CURLcode file(struct connectdata *conn)
 {