From: Jano Svitok <jan.svitok@...>
Date: 2007-07-12T23:26:34+09:00
Subject: Re: getting gdb backtrace from ruby exception

On 7/12/07, Alex Fenton <aff28@deleteme.cam.ac.uk> wrote:
> Hi
>
> I'm working on a C extension and somewhere in itsomething is raising a
> NoMethodError. The exception is reported with the line of ruby code that
> triggered the bad call in the C extension.
>
> As the C code is large and complex (it's a big SWIG project), I'm having
> trouble finding the problem in the C code. I would use gdb or
> Microsoft's debugger to look at the stack if it was a C error - but when
> a Ruby exception is raised, the process exits and there's no stack to
> inspect.
>
> Ruby's debugger isn't helpful because it only knows about ruby written
> in ruby.
>
> Is there any way I can get at the C stack at the point of ruby 'raise'
> from a C extension?
>
> Thanks
> alex

There was a way how to run ruby under gdb with the ability to debug at
"ruby level" while still having the "C view" at hand.

http://eigenclass.org/hiki.rb?ruby+live+process+introspection
http://weblog.jamisbuck.org/2006/9/25/gdb-wrapper-for-ruby
http://redhanded.hobix.com/inspect/theRubyGdbArmsRaceNowAtAStandoff.html

J.