Hi.
Last couple of days we noticed that when some of our tests fail, they simply abort ruby process without any clues. It took me some time to figure out that this was a combination of two bad thigs. First is broken line numbers in exceptions from compiled templates, second is a MRI 'feature' which promotes any exception raised in #backtrace to fatal error.
Broken line numbers caused TemplateError#backtrace to fail which in turn caused whole process to die silently.
Fix and test for broken line numbers is here http://dev.rubyonrails.org/ticket/10937
To mitigate second issue I propose generating backtraces eagerly in #initialize. See second patch: http://dev.rubyonrails.org/ticket/10936
I had a tough GDB session to find out what's wrong, so I think that at least #10936 should be applied ASAP.