diff --git a/flash.h b/flash.h
index 3d86836..00b4c80 100644
--- a/flash.h
+++ b/flash.h
@@ -30,7 +30,7 @@
 #include <stdint.h>
 #include <stdio.h>
 
-#ifdef __FreeBSD__
+#if defined(__FreeBSD__)
   #include <machine/cpufunc.h>
   #define off64_t off_t
   #define lseek64 lseek