diff --git a/library/aes.c b/library/aes.c
index da94b19..797e00f 100644
--- a/library/aes.c
+++ b/library/aes.c
@@ -36,6 +36,7 @@
 #include <string.h>
 
 #include "mbedtls/aes.h"
+#include "mbedtls/utils.h"
 #if defined(MBEDTLS_PADLOCK_C)
 #include "mbedtls/padlock.h"
 #endif
@@ -54,11 +55,6 @@
 
 #if !defined(MBEDTLS_AES_ALT)
 
-/* Implementation that should never be optimized out by the compiler */
-static void mbedtls_zeroize( void *v, size_t n ) {
-    volatile unsigned char *p = (unsigned char*)v; while( n-- ) *p++ = 0;
-}
-
 /*
  * 32-bit integer manipulation macros (little endian)
  */