diff --git a/tools/sdk/include/c_types.h b/tools/sdk/include/c_types.h
index 1073600a0..9d94a025f 100644
--- a/tools/sdk/include/c_types.h
+++ b/tools/sdk/include/c_types.h
@@ -8,6 +8,7 @@
 #include <stdint.h>
 #include <stdbool.h>
 #include <stdarg.h>
+#include <sys/cdefs.h>
 
 typedef signed char         sint8_t;
 typedef signed short        sint16_t;
@@ -40,8 +41,6 @@ typedef double              real64;
 
 #define __le16      u16
 
-#define __packed        __attribute__((packed))
-
 #define LOCAL       static
 
 #ifndef NULL