[Haskell-cafe] Obscure weirdness

Lennart Augustsson lennart at augustsson.net
Sat Jun 20 16:42:30 EDT 2009

Did you try running it in some debugger, like windbg or VS?

2009/6/20 Andrew Coppin <andrewcoppin at btinternet.com>:
> Marcin Kosiba wrote:
>> On Saturday 20 June 2009, Andrew Coppin wrote:
>>> OK, so here's an interesting problem...
>>> I've been coding away all day, but now my program is doing something
>>> slightly weird. For a specific input, it summarily terminates. The
>>> registered exception handler does not fire. There is no output to stdout
>>> or stderr indicating what the problem is. It just *stops* half way
>>> through the printout.
>>> Weirder: If I run it in GHCi, then GHCi itself terminates. (I didn't
>>> think you could *do* that!)
>> Hi,
>>        With the information you've provided it's hard to even guess. At
>> least take a look at your app's RAM usage -- it just may be that its
>> allocating too much memory and the OOM killer is killing it (if you're
>> running linux, that is).
>>        You may also want to try the GHCi debugger [1] to find out where
>> the program crashes. The last thing I'd do is blame it on ghc/ghci, but as
>> always -- such a possibility exists.
> It's Windows. And while it's possible (indeed even probable) that my code
> has an infinite loop in it somewhere, usually that makes the program slow to
> a crawl and start thrashing the HD as it hits virtual memory. But this
> program just dies. Instantly.
> And I already tried the GHCi debugger. When I run the program, GHCi just
> quits. I suppose if I can track down exactly *where* in the program it's
> dying, I could try single-stepping through it...
> If I was doing something tricky like FFI or unsafe coersions, I'd assume I'd
> got it wrong somewhere. But I'm just doing plain ordinary Haskell stuff -
> traversing trees, pattern matching, etc. I'm a bit perplexed that it can
> fail this way.
> _______________________________________________
> Haskell-Cafe mailing list
> Haskell-Cafe at haskell.org
> http://www.haskell.org/mailman/listinfo/haskell-cafe

More information about the Haskell-Cafe mailing list