diff --git a/stmhal/hal/f4/inc/stm32f4xx_hal_def.h b/stmhal/hal/f4/inc/stm32f4xx_hal_def.h
index 11ae7a1cf5..e7858ac2c9 100644
--- a/stmhal/hal/f4/inc/stm32f4xx_hal_def.h
+++ b/stmhal/hal/f4/inc/stm32f4xx_hal_def.h
@@ -47,7 +47,9 @@
 /* Includes ------------------------------------------------------------------*/
 #include "stm32f4xx.h"
 #include "Legacy/stm32_hal_legacy.h"
-#include <stdio.h>
+#ifndef NULL
+#define NULL (void*)0
+#endif
 
 /* Exported types ------------------------------------------------------------*/