I just updated to the latest (18.3.0) version of Parallels Desktop, and this error is still occurring:
Code:
FATAL: modpost: GPL-incompatible module prl_eth.ko uses GPL-only symbol 'cc_platform_has'
I realize this is a sketchy fix, but hacking the license declared in kmods/prl_eth/pvmnet/pvmnet.c to "GPL" fixes it. As far as I can tell, the code doesn't even use the named symbol.