diff --git a/library/oid.c b/library/oid.c
index e42f20d..3cca1fa 100644
--- a/library/oid.c
+++ b/library/oid.c
@@ -33,12 +33,13 @@
 #include "polarssl/oid.h"
 #include "polarssl/rsa.h"
 
+#include <stdio.h>
+#include <string.h>
+
 #if defined(POLARSSL_X509_USE_C) || defined(POLARSSL_X509_CREATE_C)
 #include "polarssl/x509.h"
 #endif
 
-#include <stdio.h>
-
 /*
  * Macro to automatically add the size of #define'd OIDs
  */