We recently changed the host compiler in ChromeOS from GCC to LLVM/Clang, and apparently that is the root cause of your issue.  If you could tell me what package you are building, I can set things up for your package to build with GCC at the moment.  I am working on another CL that, when it goes in, should allow your package to build with clang.

My package is not in the repo yet. It is in platform/puffin which is empty now. I can temporary build everything with emerge-$BOARD, but that is not the intended purpose. Is there anyway I can set it up myself? How long does it take for you new CL to go in?

Thanks,

In /etc/make.conf.host_setup, the very last two lines of the file define CC & CXX to be clang & clang++.  If you comment out those lines and then redo your setup_board, that should revert the default compiler to GCC for you.

Umm...I just tried what I suggested.  I think you need to edit the file and NOT do the setup_board.  Sorry.

Yes, it works now. Thank you for your help.

It took a little longer than I expected but my CLs to 'really' fix this issue have all been committed now, so your workaround should not be needed any more.  I am going to mark this as fixed.