[Haskell-cafe] Compiler's bane

[Andrew Coppin]

Here is a *much* bigger problem: How do you check that an interpretter 
is correct??

You can't very easily write a QuickCheck property that will generate 
every possible valid expression and then check that the output of the 
interpretter is formally equivilent. The QuickCheck property would be a 
second copy of the interpretter, which proves nothing!

Any hints? Just how *do* you check something large like this?

I wonder - how do the GHC developers check that GHC works properly? (I 
guess by compiling stuff and running it... It's a bit harder to check 
that a lambda interpretter is working right.)