Thanks for the testing. Some more data to consider: - When I build with 1 CPU, I have never found the build problem so far. - When I build with 2 CPUs, I got a failure rate of 66% (16 failures over 24 tries so far). - Given that 66% > 50%, "does not build from source" is more true than "builds from source" (so please do not downgrade).
Given the above, my suspect is that this could be a Makefile bug, and that it will not fix itself by merely doing another upload. I would try how it behaves when using --no-parallel. Thanks.
