Crazy loader bug

[Tritlo]

So what was happening was that files were being shared between GHC processes. This still happens, but in a limited fashion (and less now that we pre-compute the fixes). I think we saw it happen only in PseudoGenetic because that's doing it old-school, and not assembling fixes from previous ones, but rather constantly creating new ones (so a lot more compilation going on?). I think what must have happened is that the linker would read some incomplete object of interface file, and just totally crash.

Anyway, it seems to be working safely now with the new randomizeHiDir and randomizeHpcDir which mitigate the parallel file problem somewhat. Hopefully we'll see some practical results soon!