..  Copyright (c) 2014-present PlatformIO <contact@platformio.org>
    Licensed under the Apache License, Version 2.0 (the "License");
    you may not use this file except in compliance with the License.
    You may obtain a copy of the License at
       http://www.apache.org/licenses/LICENSE-2.0
    Unless required by applicable law or agreed to in writing, software
    distributed under the License is distributed on an "AS IS" BASIS,
    WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    See the License for the specific language governing permissions and
    limitations under the License.

.. _library_json_buid_flags:

``flags``
~~~~~~~~~

*Optional* | Type: ``String`` or ``Array``

Extra flags to control preprocessing, compilation, assembly, and linking
processes. More details :ref:`projectconf_build_flags`.

.. note::
    Keep in mind when operating with the ``-I`` flag (directories to be
    searched for header files). The path should be relative to the
    root directory where the ``library.json`` manifest is located.
