diff --git a/library/ssl_tls13_client.c b/library/ssl_tls13_client.c
index d599ef3ae..7f120a28e 100644
--- a/library/ssl_tls13_client.c
+++ b/library/ssl_tls13_client.c
@@ -21,7 +21,7 @@
 
 #include "common.h"
 
-#if defined(MBEDTLS_SSL_CLI_C) &&defined(MBEDTLS_SSL_PROTO_TLS1_3)
+#if defined(MBEDTLS_SSL_CLI_C) && defined(MBEDTLS_SSL_PROTO_TLS1_3)
 
 #include <string.h>