Re: [Chicken-users] a memory issue; mildly scaring to me

[Peter Bex]

On Mon, Sep 26, 2011 at 03:16:07PM +0200, Jörg F. Wittenberger wrote:
> >While it does not fix the problem at hand:
> >
> >There is a suspicious line in regex-core.scm 2222:
> >
> >it reads:
> >
> >   (printing or graphic whitespace)
> >
> >IMHO it should read:
> >
> >   (printing . (or graphic whitespace))
> 
> BTW: I know that those are the same.  It's just confusing the reader,
> when the same list is written both styles.

Maybe. This can be fixed, but it's not the issue here.

> Ah: since parameter checking might be off in the chicken core (is it?),
> what would happen, if we use a parameter, which has not been passed?
> Might that be the uninitialized value from a stack allocation, which
> I see from valgrind?
>
> What should be done?

Why don't you try your regex code with upstream irregex itself?

Just (load "irregex.scm") and then run your regex match.
Then it will run with all checks enabled, at slow speed, but at least
it'll fail when something is broken.

All this speculation is kind of pointless without a proper testcase.

Cheers,
Peter
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