diff --git a/library/pk_wrap.c b/library/pk_wrap.c
index 5446e23..2e09711 100644
--- a/library/pk_wrap.c
+++ b/library/pk_wrap.c
@@ -41,6 +41,10 @@
 #include "mbedtls/ecdsa.h"
 #endif
 
+#if defined(MBEDTLS_PK_RSA_ALT_SUPPORT)
+#include "mbedtls/utils.h"
+#endif
+
 #if defined(MBEDTLS_PLATFORM_C)
 #include "mbedtls/platform.h"
 #else
@@ -52,13 +56,6 @@
 #include <limits.h>
 #include <stdint.h>
 
-#if defined(MBEDTLS_PK_RSA_ALT_SUPPORT)
-/* Implementation that should never be optimized out by the compiler */
-static void mbedtls_zeroize( void *v, size_t n ) {
-    volatile unsigned char *p = v; while( n-- ) *p++ = 0;
-}
-#endif
-
 #if defined(MBEDTLS_RSA_C)
 static int rsa_can_do( mbedtls_pk_type_t type )
 {