diff --git a/library/x509write_crt.c b/library/x509write_crt.c
index 5947e43..2baff35 100644
--- a/library/x509write_crt.c
+++ b/library/x509write_crt.c
@@ -25,11 +25,7 @@
  * - attributes: PKCS#9 v2.0 aka RFC 2985
  */
 
-#if !defined(MBEDTLS_CONFIG_FILE)
-#include "mbedtls/config.h"
-#else
-#include MBEDTLS_CONFIG_FILE
-#endif
+#include "common.h"
 
 #if defined(MBEDTLS_X509_CRT_WRITE_C)