[ludocode]

The current version of rustc may compile itself quickly, but remember, this is after nearly ten years of compiler optimizations. Older versions were much slower.

I seem to recall complaints that old rustc would take many hours to compile itself. Even if it takes on average, say, two hours to compile itself, that's well over a week to bootstrap all the way from 0.7 to present. You're right that months is probably an exaggeration, but I suspect it might take a fair bit longer than a week. The truth is probably somewhere in the middle, though I suppose there's no way to know without trying it.