[html-formfu] Debugging segmentation faults

[ivorw]

Stephen Shorrock wrote:
> Dear List,
>  
> I'd just like to say that I haven't been using FormFu for long. Infact
> only since your link appeared on the Catalyst list.  In that short
> time though I've been impressed at how easy it has made form
> generation, it could certainly save a lot of work.
>  
> I do have a bit of a problem however.  It might not be FormFu, but my
> usage of FormFu has coincided with segmentation faults appearing in my
> Apache error_log.  These segmentation faults seem to appear after
> three of four consecutive requests to a   : FormConfig Catalyst
> Controller Action.
>  
It's unusual to get segfaults in pure perl code. I'm not aware of FormFu
using any XS code itself, but it could be something that your app is
calling. When you do find the culprit module, it's well worth filing a
bug report on RT, or on perlbug if the problem is with perl itself.
> I was wondering whether anyone had experience of debugging these sorts
> of errors withing Apache and Catalyst, what's the best way to go about
> doing this?
I take it you're running your app via mod_perl. Can I recommend that you
switch to running it as a standalone FastCGI process farm, perhaps with
just a single instance running. You can get the process to save a core
dump when it segfaults, which you can then use to get a stack trace,
hence find what it's doing.
>  
> Maybe it could be simply something wrong with the FormFu config that I
> am using?
>  
Probably not (see above), but perhaps you could attach the config so we
can give better judgement.

Ivor.