Some good-hearted criticism (Was: Biggest Haskell unit in the world)

Malcolm Wallace Malcolm.Wallace@cs.york.ac.uk
Tue, 26 Jun 2001 11:01:50 +0100


>     Second, debugging tools. So far, I haven't been able to figure out why 
> my program (a parser for C++ comments and strings) generates stack 
> overflows. Nothing I've been able to think up has been of any help. Neither 
> has the suggestions I got from the mailing list. GHC is supposed to have 
> nice profiling utilities but it won't work in my installation no matter 
> what I try (the program crashes), and, in any case, I haven't seen in the 
> documentation any stack-debugging options.

I would be more than happy to spend a little time pushing your program
through the Hat debugging and tracing tools to see what we can find.
Nhc98's heap profiling should also reveal interesting things, and
I'll do that too if you like.  There is a well-known caveat however,
that different compilers produce code with different space behaviour,
so I can't even guarantee that your program will exhibit a stack
overflow when built with nhc98!

>     So, now I repeat my plea for help. At this point, I don't care much if 
> I don't get the program to work. But I _NEED_ to know what was wrong. Maybe 
> one of you teachers might want to use the program as an exercise in 
> diagnosing a program for the students? I can send it in a pinch: it's just 9K.

Great, send me a copy.  And some test data (with expected results,
if that is relevant).

Regards,
    Malcolm