diff --git a/platform/win32/contiki-conf.h b/platform/win32/contiki-conf.h
index 45ce9efa1..bc8909d87 100644
--- a/platform/win32/contiki-conf.h
+++ b/platform/win32/contiki-conf.h
@@ -21,7 +21,7 @@
 
 #define LOG_CONF_ENABLED 1
 #include "sys/log.h"
-void debug_printf(char *format, ...);
+CCIF void debug_printf(char *format, ...);