LoRaWAN client code stopped compiling due to missing RADIOLIB_ERR defines

[sten-senarch]

We have a device based on a RP Pico that communicates via LoRaWAN.
I wanted to build the software for it on a new machine, and checked out the code as well as RadioLib as a submodule.

The source code for the client has now stopped compiling due to "RADIOLIB_ERR_N_FCNT_DOWN_INVALID" and "RADIOLIB_ERR_A_FCNT_DOWN_INVALID" not being found in the scope of the function that use them.
I can not find reference to them in the current source for RadioLib.
But I can see they were deleted in TypeDef.h updated on May 29th.

Question: Are they no longer valid errors? Or should we do things in a new way?

[StevenCellist]

Hi @sten-senarch, good question! A 7.2 release is pending with a note for the removal of these error codes. These error codes are not used anymore, as RadioLib now always tries a rollover of the 16-bit FCnt value instead of using the MaxFCntGap limit which I erroneously implemented.
An invalid FCnt will now always be attempted to verify the MIC, and if it is indeed invalid, will return MIC_MISMATCH which is the new name of the error code -1112.

[sten-senarch]

I see - very well. I willl remove them from our code.
I must confess I have inherited the code, so I can't comment at this stage on whether the specific handling of FCnt needs revision in our code, but I appreciate the guidance.
Many thanks!

[StevenCellist]

Without seeing your code, I think there is nothing really to be done about an invalid FCnt - the code is mostly there to help in case really weird things happen. But realistically, you should almost never encounter it and if it so happens, the device can do nothing about it.
So in short, you don't need to handle those error codes individually. Just a general error handler should be good in my opinion :)