As a day-time java programmer, I can say from experience that sometimes (100% pure) Java programs DO segfault.
I've had it happen to me, and while you can justifiably say it's an error in the JVM somehow triggered by your program behaviour/timing, that doesn't help you very much at the time.
Sure, and just as java has its runtime, so does Haskell. Runtimes are software and prone to being buggy. Runtimes are often written in languages like C where bugs can lead to memory corruption, crashes and arbitrary malicious code execution. Here's a small example that I unfortunately ran across today: ghc -c wxdirect/src/CompileClassTypes.hs -o dist/wxdirect/CompileClassTypes.o -idist/wxdirect -odir dist/wxdirect -hidir dist/wxdirect -package parsec -cpp -package time Segmentation fault (core dumped) :(
Maarten Hazewinkel
The point being that Haskell, while having a theorem checker that helps programmers find and avoid bugs and while being based on semi-formal concepts that can be used to avoid some pitfalls, is still no silver bullet against any and all crashes. Promising would-be converts that it is will only lead to disappointment. Tim Newsham http://www.thenewsh.com/~newsham/