@maxgerhardt thanks for shedding some light on this. now it makes some sense 
unfortunately most arduino libs are header only
I’m using same pio version on both windows and mac and already on dev channel 5.2.0b1
(can this be the reason?)[c - clang makefile "ar: no archive members specified" - Stack Overflow]
yes, this fixes the issue for me, 
, should I mark this as resolved when my problem is fixed but the issue still persists?