diff --git a/programs/ssl/ssl_server2.c b/programs/ssl/ssl_server2.c
index 03eda0bf76..a94ddac8ee 100644
--- a/programs/ssl/ssl_server2.c
+++ b/programs/ssl/ssl_server2.c
@@ -924,7 +924,8 @@ int sni_callback( void *p_info, mbedtls_ssl_context *ssl,
 
 #endif /* SNI_OPTION */
 
-#if defined(MBEDTLS_KEY_EXCHANGE__SOME__PSK_ENABLED)
+#if defined(MBEDTLS_KEY_EXCHANGE__SOME__PSK_ENABLED) || \
+    defined(MBEDTLS_SSL_CID)
 
 #define HEX2NUM( c )                        \
     do                                      \
@@ -967,6 +968,10 @@ int unhexify( unsigned char *output, const char *input, size_t *olen )
     return( 0 );
 }
 
+#endif
+
+#if defined(MBEDTLS_KEY_EXCHANGE__SOME__PSK_ENABLED)
+
 typedef struct _psk_entry psk_entry;
 
 struct _psk_entry