Basically just learning haskell, I would have posted this in the beginners list but since it involves a segfault of GHCI, I figured it might be worth posting here. 

I was trying to get a good understanding of local variable scoping issues, so I tried the following:

f :: (Num a) => a -> a
f x =
    let p = x*x
    in
        let p = x*p
        in p

I have some background in ML, which led me to believe that what should happen here is that the function would return x^3.  Instead, GHCI just completely terminates, I guess with a segfault.  What's the "correct" behavior here?  Should it even compile?  I understand that you can't redefine the same symbol twice in the same scope, so I tried this specifically to see what would happen if you defined the same variable again in a nested scope.  I thought it would just shadow the original declaration, while still using the original p to calculate the value of the new p.  I don't think the problem is the re-declaration of the same symbol in a nested scope (although if someone could clarify that would be nice), but rather the fact that I've attempted to use the previous declaration of p in defining the new declaration of p.

Would it be a safe assumption that a bug report should be submitted over this?