From: Daniel Berger <djberg96@...>
Date: 2005-07-16T00:20:52+09:00
Subject: Re: RoR example and segmentation fault!

JZ wrote:
> I tried add new ticket "Elite Journal" example I found in docs section of
> RoR but I get "Precondition Failed. The precondition on the request for the
> URL /newticket evaluated to false." So I send the problem here:
>
> PROBLEM: After login I cannot click on anything because I get segmentation
> fault :( I am using windows xp pro sp2. The problem looks serious and I am
> afraid of stability RoR on win32 system...

<snip>

> c:/opt/ruby/lib/ruby/gems/1.8/gems/activesupport-1.1.1/lib/active_support/core_e
> xt/string/../../inflector.rb:41: [BUG] Segmentation fault
> ruby 1.8.2 (2004-12-25) [i386-mswin32]
>
> This application has requested the Runtime to terminate it in an unusual
> way.Please contact the application's support team for more information.
> ---------------------------------

Curious.  Line 41 of inflector.rb is simply this:

class_name_in_module.to_s.gsub(/^.*::/, '')

This converts strings like "Foo::Bar" to "Bar".  I've done some testing
with .to_s.gsub in order to try to cause a segfault on my WinXP Pro
box, but I can't do it.  I've tried millions of iterations using empty
strings, nil, numbers - still works fine.

To narrow it down, add the following code above line 41:

File.open("C:\\temp.log","w+"){ |fh|
   fh.puts("class name was: #{class_name_to_module}")
}

Next time it segfaults, take a look at temp.log and see what it says.
If that isn't helpful, try replacing line 41 with this line:

class_name_in_module.to_s.split("::").last

It does the same thing, though it's a bit slower.  If it works, then we
know it's somehow related to gsub.  If it doesn't work, then the real
issue lies elsewhere.

Regards,

Dan