Race in testsuite runner
I have seen this error periodically for the last several months:
Framework failures:
generics/T5462Yes1.run T5462Yes1 [[Errno 2] No such file or directory: '/builds/ghc/ghc/testsuite/tests/generics/GFunctor/GFunctor1.run/GFunctor.o.tmp4e9f655'] (threaded1)
It looks like some sort of race condition. Unfortunately, the error doesn't contain enough to context to identify where the issue originates.