Hello,
check your linker options of the project. You have something like this in it, probably starting with --start-group:
arm-none-eabi-gcc: error: unrecognized command line option '--undefined=__pformatter_'
arm-none-eabi-gcc: error: unrecognized command line option '--defsym=__pformatter=__pformatter_'
arm-none-eabi-gcc: error: unrecognized command line option '--start-group'
arm-none-eabi-gcc: error: unrecognized command line option '--end-group'
These are from the CW project, settings for the EWL libraries.
I hope this helps,
Erich