diff --git a/ext/mysql/php_mysql.c b/ext/mysql/php_mysql.c
index 6184d44260b..a591f448968 100644
--- a/ext/mysql/php_mysql.c
+++ b/ext/mysql/php_mysql.c
@@ -586,7 +586,7 @@ static void php_mysql_do_connect(INTERNAL_FUNCTION_PARAMETERS, int persistent)
                 	client_flags ^= CLIENT_LOCAL_FILES;
 		}
 
-		hashed_details_length = spprintf(&hashed_details, 0, "mysql_%s_%s_%s_%d", SAFE_STRING(host_and_port), SAFE_STRING(user), SAFE_STRING(passwd), client_flags);
+		hashed_details_length = spprintf(&hashed_details, 0, "mysql_%s_%s_%s_%ld", SAFE_STRING(host_and_port), SAFE_STRING(user), SAFE_STRING(passwd), client_flags);
 	}
 
 	/* We cannot use mysql_port anymore in windows, need to use