How to get a backtrace from a SystemStackError: stack level too deep?

Another method for those finding this question later… An excellent gist provides instructions on enabling a trace function in the console and printing all function calls to a file. Just tested on 1.9.3-p194 and it worked great.

Including here in case the gist goes away someday:

$enable_tracing = false
$trace_out = open('trace.txt', 'w')

set_trace_func proc { |event, file, line, id, binding, classname|
  if $enable_tracing && event == 'call'
    $trace_out.puts "#{file}:#{line} #{classname}##{id}"
  end
}

$enable_tracing = true
a_method_that_causes_infinite_recursion_in_a_not_obvious_way()