Hello All!
I've been running Rails 2.0.2 with Ruby 1.8.6 for the last six months. I developed an application that runs fine on two different servers -- or at least, it used to.
I used Mongrel as a development server, but requirements called for using Apache for a production deployment. I found Phusion Passenger (mod_rails) and decided to give it a try.
I decided to update my rubygems to the latest version before
installing Passenger, so I did a "gem update --system". A slew of
gems were updated (at least six or eight). All seemed fine until I
tried actually using my application again 
Now the application crashes when it tries to access any of my named routes. Rubygems cores, usually with a segmentation fault, generating messages like this in /var/log/httpd/error_log:
*** glibc detected *** Rails: /var/www/rails/wave: double free or corruption (out): 0x0a188d90 ***
and
Premature end of script headers: users, referer: http://shrimp/wave
and
/usr/lib/ruby/gems/1.8/gems/actionpack-2.0.2/lib/action_view/helpers/ url_helper.rb:488: [BUG] Segmentation fault
and
/usr/lib/ruby/gems/1.8/gems/actionpack-2.0.2/lib/action_view/ template_error.rb:78: [BUG] Segmentation fault
I tried using both mod_rails and mongrel to serve the application, but both give the same results.
In hindsight I should have done a backup before the update, but my hindsight seems a lot better than my foresight lately.
So now we finally come to my question: How do I undo the mess I made? Is there a log somewhere that tells me specifically which versions of which gems were updated, and is there an easy way to roll back to a specific version?
Even better would be if someone else has seen the same problem and knows of a patch or update that would allow me to use the updated gems... but I figure that's probably asking too much.
One more thing: My development environment is Fedora Core 8 and I have the yum updatesd service running. I've noted at least two Ruby "security" updates over the last week, so I'm also wondering if anything pushed down via that route might be causing (or at least contributing to) my problems...
Greg