We've been getting intermittent reports of it failing, but I've been unable
to reproduce so far. The test in question is a compiler scaling test, which
compares times it takes to compile different things. Brittle, indeed.
Other than non-SBCL causes the only thing I can think of right now is GCs
from other tests getting accounted against one of the supposed-to-be-fast
runs. So, run GC :FULL T before getting the timings to make things more