Segfault under Rack/Passenger

[aaronbarnett]

Using rsruby in a sinatra/rack app.

def initialize(app)
    super(app)
    @r = RSRuby.instance
end

get '/test.json' do
    content_type 'text/plain'
    out = @r.seq(1,9)
    out.to_json
end

The calls to R work as expected in irb and when ruby is run from the command line. They fail when run through rackup or with passenger. Log contains a lot of this...

App 29404 stderr: Error during wrapup: C stack usage is too close to the limit
App 29404 stderr: Error during wrapup: C stack usage is too close to the limit
App 29404 stderr: Error during wrapup: C stack usage is too close to the limit
App 29404 stderr: Error during wrapup: C stack usage is too close to the limit
App 29404 stderr: Error during wrapup: C stack usage is too close to the limit

In rsruby.rb I commented out the error trapping

#Catch errors
# self.__init_eval_R__("options(error=expression(NULL))")
#disable errors
# self.__init_eval_R__("options(show.error.messages=F)")

This reveals a little more detail

App 27581 stderr:  *** caught segfault ***
App 27581 stderr: address 0x11000088, cause 'memory not mapped'
App 27581 stderr: aborting ...
[ 2014-03-26 16:20:36.8674 27558/0x1091c2000 Pool2/SmartSpawner.h:689 ]: An error occurred while spawning a process: An error occurred while starting the web application. It exited before signalling successful startup back to Phusion Passenger.
[ 2014-03-26 16:20:36.8674 27558/0x1091c2000 Pool2/SmartSpawner.h:690 ]: The application preloader seems to have crashed, restarting it and trying again...

Moving the call to RSRuby.instance into the controller causes similar errors. Also if @r.seq(1,9) is moved into the initialize block it performs as expected. It seems that the controller environment is where any reference into rsruby fails.

[stanley90]

I'm experiencing similar failures, having the RSRuby instance in the application controller, and running capybara tests. Started failing with "segfault" and "stack smashing detected" after upgrading capybara from 1.1.4 to 2.x.

[linojon]

We're experiencing very similar problems, after upgrading from Passenger 3 to Passenger 4. Happens running ruby 1.9.3 as well as 2.1.1, and Rails 3.2 as well as 4.0. Runs fine when calling R through RSRuby in the rails console, but gets "C stack usage is too close to the limit" and then segfault in the Apache log

[eliagilad]

I've noticed that it works just fine with Unicorn, but not with WEBrick or Sidekiq.
Any idea how to solve it?

[athityakumar]

Has anyone found a workaround for this yet? I'm facing the same issue with Rails 5.1.3.

[athityakumar]

Hey all. Strangely enough, athityakumar@bf2b0f4 fixed the issue for me. However, I'm not sure if it's a good approach to comment out the RException class.

@alexgutteridge - Please guide me if something is wrong with that commit. I can work on a PR. 😄

[altrabio]

I am facing the same kind of issue (passenger 4.0.37, ruby 1.9.3) ? The fix proposed by athityakumar does not work for me. Has anyone another workaround. (Note that the segmentation fault is not systematic).
Thanks