diff --git a/library/pem.c b/library/pem.c
index 31f4a9a..544f7c4 100644
--- a/library/pem.c
+++ b/library/pem.c
@@ -19,11 +19,7 @@
  *  This file is part of mbed TLS (https://tls.mbed.org)
  */
 
-#if !defined(MBEDTLS_CONFIG_FILE)
-#include "mbedtls/config.h"
-#else
-#include MBEDTLS_CONFIG_FILE
-#endif
+#include "common.h"
 
 #if defined(MBEDTLS_PEM_PARSE_C) || defined(MBEDTLS_PEM_WRITE_C)