ESP32 flags unused function as error (should be warning)

[RobTillaart]

The ACS712 library has a function static uint16_t _internalAnalog(uint8_t pin) that is not used by the examples.

The build sees this function is not used and generates an error on this, imho this should be a warning,
All other platforms tested do not report it as error.

Flag: -Werror=unused-function

build
https://github.com/RobTillaart/ACS712/actions/runs/3924992021/jobs/6747518244

[RobTillaart]

Solved the specific library in another way, so my acute problem is solved,
Still I think this should be solved as compilation should only warn for unused variables and functions.
(for now low prio)

[ianfixes]

Did you resolve this via the .arduino-ci.yml configuration YAML file, or some other way?

[ianfixes]

The compilation of examples is delegated to the arduino-cli binary, and you should probably report it upsteam. But I can continue to track this here in case there is a possible workaround.

[RobTillaart]

Did you resolve this via the .arduino-ci.yml configuration YAML file, or some other way?

Completely different, I moved the static function that caused the error into the class as a normal function.

I had the static function as a wrapper around analogRead() which has a different signature on different platforms.
I needed a way to handle those differences as casting functions is a "no go" area.
Requirement was to be able to replace internal ADC with external ADC.

Now I have a private function in the class that looks if an external ADC is set, if not it uses internal.
In the end quite elegant imho.

[vzahradnik]

I reported this issue upstream as I'm facing with the same issue and I can't do the suggested workaround.
arduino/arduino-cli#2252

[ianfixes]

This issue is caught up in a much more complicated discussion, and currently I'm not optimistic about the outcome arduino/ArduinoCore-API#25

[vzahradnik]

@ianfixes your expectations are correct. The decision to consider warnings as errors comes from the ESP32 boards platform developers. Why they decided to go with such a strict requirement is not clear to me. We are not building firmware for space travels :)

Anyway, the only solution known to me is to comply which means to fix the library. In my case, the library is unmaintained, last commit was 5-years ago.

[vzahradnik]

I suggest to close this issue.

[RobTillaart]

Agree on closing the issue

We are not building firmware for space travels :)

You never know for sure!
just Google on Arduino and CubeSat

• https://www.instructables.com/How-to-Build-a-CubeSat-With-an-Arduino-With-an-Ard/