Crashing on RasberryPI

Bug reports and questions about running Virtual Radar Server on Linux
Celestial
Posts: 8
Joined: Thu Feb 06, 2014 9:44 pm

Crashing on RasberryPI

Post by Celestial » Thu Feb 06, 2014 9:51 pm

I have gotten everything running or at least it appears this way. When VRS 2.0.0 starts up it runs fairly well for 20-30 seconds but then gives me an assertion:

* Assertion at mini-codegen.c:798, condition `i == sel' not met

Stacktrace:
at <unknown> <0xffffffff>
[...]

I am not really sure if I am loading this correctly - do I need to start dump1090? (That is working btw).

Cheers...

agw
Posts: 2241
Joined: Fri Feb 17, 2012 3:20 am

Re: Crashing on RasberryPI

Post by agw » Fri Feb 07, 2014 10:10 am

Anything that has an extension of ".c" in the error message is going to be coming out of Mono rather than the program itself. It used to be the case that the Mono that gets installed when you do apt-get install mono-complete on the Raspberry wasn't suitable for use with VRS because it used software floating point instead of hardware floating point, which caused problems with Mono's WinForms implementation. It looks like this may change fairly soon, hardware floating point support for the Pi was added in December. However at the moment that version is not in the repository - you have to compile the hardware floating point version by hand, which can apparently take a few hours (http://c-mobberley.com/wordpress/2013/1 ... ompatible/).

I'll have a go over the weekend at building a hardware floating point Mono and seeing if that works alright with VRS, but as things stand if you're using the Mono that's installed via apt-get then I'm afraid it's unlikely to work with VRS. Although if you are then I'm surprised you managed to get as far as 20 seconds of runtime, I seem to remember it crashed pretty quickly.

Celestial
Posts: 8
Joined: Thu Feb 06, 2014 9:44 pm

Re: Crashing on RasberryPI

Post by Celestial » Fri Feb 07, 2014 10:48 pm

So perhaps I should have been more alert and provided some additional information ;-)

VRS will start up and run quite happily as long as I don't touch it. (Not very useful, I know.) The crash occurs as soon as I try top open up Tools/Options It doesn't matter if I start it sudo (which was my first thought.)

My RPi is running Raspbian 3.10.25+ which is fairly recent.

Thanks in advance.

agw
Posts: 2241
Joined: Fri Feb 17, 2012 3:20 am

Re: Crashing on RasberryPI

Post by agw » Sun Feb 09, 2014 12:21 am

Yes, crashes when you try to open the options screen rings a bell :) I think that was happening with a previous attempt at using a hardware FP version of Mono. Which version of Mono are you using?

Celestial
Posts: 8
Joined: Thu Feb 06, 2014 9:44 pm

Re: Crashing on RasberryPI

Post by Celestial » Wed Apr 30, 2014 4:54 pm

Umm, I'm not really sure - I just installed mono-complete. How would I find out the version?

(Sorry I didn't see this earlier. I finally got my Cubox-i and have been playing with that.)

agw
Posts: 2241
Joined: Fri Feb 17, 2012 3:20 am

Re: Crashing on RasberryPI

Post by agw » Thu May 01, 2014 12:31 am

I think if you do mono --version it tells you the version number.

It used to be that the version that was installed with mono-complete on the Pi didn't have hardware floating point, but if you're managing to get as far as the main screen then I'm guessing that's no longer the case. I'll have a play and see if I can reproduce it, but if Mono is crashing out then it'll be a case of me trying to find a workaround that doesn't trigger the crash, doesn't involve me rewriting half the UI and doesn't break the Windows version or other working Mono versions. It's not always an easy trick to pull off.

Celestial
Posts: 8
Joined: Thu Feb 06, 2014 9:44 pm

Re: Crashing on RasberryPI

Post by Celestial » Mon May 05, 2014 7:13 pm

So I finally got my CuBox-i (pro version) running on it and I'm crashing at the same place (launching the Options dialogue).

The PI version is:
Mono JIT compiler version 3.2.3 (Debian 3.2.3 + dfsg-5+rpi1)

The Cubox is:
Mono JIT compiler version 3.2.8 (Debian 3.2.8+DFSG-4ubuntu1)
(The Cubox is running ubuntu 14.04 Trusty but with the KDE window manager.)

Other info is the same for both boxes:

TLS: __thread
SIGSEGV: normal
Notifications: epoll
Architecture: armel,vfp+hard
Disabled: none
Misc: softdebug
LLVM: supported, not enabled.
GC: sgen

I have LLVM installed on the Cubox too.

Some other info on the Cubox-i is that I get the following:

=================================================================

KDE colorscheme read failure, using built-in colorscheme
* Assertion at mini-codegen.c:807, condition `i == sel' not met

Followed by a huge stactrace that ends with:
=================================================================
Got a SIGABRT while executing native code. This usually indicates
a fatal error in the mono runtime or one of the native libraries
used by your application.
=================================================================

agw
Posts: 2241
Joined: Fri Feb 17, 2012 3:20 am

Re: Crashing on RasberryPI

Post by agw » Tue May 06, 2014 4:16 am

I wouldn't be surprised if there's something in Mono's implementation of WinForms property sheets that the Pi doesn't like. If it is that then it's going to be unfortunate because that's going to be a right pain to work around. However your other crash:
Celestial wrote:* Assertion at mini-codegen.c:807, condition `i == sel' not met
seems to be a problem with mono and, of all things, the WinForms TextBox control :)

http://www.raspberrypi.org/forums/viewt ... 4&p=525487

I can't work around not being able to use text boxes. If they're what's triggering the crash then the only solution is to wait for a fix from Mono.

I've been looking into writing an OSX version of VRS using MonoMac that has a native UI, it won't need to use X-Windows or Mono's implementation of WinForms and it won't look quite so much like a dog has thrown up over the screen when it runs. In principle I should be able to use OSX's image handling to draw text on the markers as well instead of having marker labels. My initial testing with it has been promising, I think it should be reasonably straight-forward although there are some issues around how plugins are implemented that would need to be sorted out. If that works out then I might have a look to see what would be involved in doing the same to produce a GTK+ version for other Linux distros. It'd be nice not to have to rely on Mono's WinForms, it's ugly and keeps throwing up these kinds of problems, but at the same time I don't want to have to maintain lots of different front-end GUIs for this thing... so at the moment I'm in two minds about it.

Celestial
Posts: 8
Joined: Thu Feb 06, 2014 9:44 pm

Re: Crashing on RasberryPI

Post by Celestial » Tue May 06, 2014 4:22 am

Thanks for the reply agw, I will try to look into other options/mono options. I'll let you know if I find anything but right now I've got to stage things for Maker Faire which is in two weeks.

Cheers,

Cel

gariac
Posts: 31
Joined: Sun Jan 13, 2013 6:25 am

Re: Crashing on RasberryPI

Post by gariac » Thu Jul 10, 2014 3:26 am

It looks like you can make windows .net using qt or tk with appropriate software. But if that makes windows VRS ugly, you have another problem.

But I have a different solution. Why can't you do the settings from a browser window than using forms? Ultimately, for VRS to be valuable, it needs to serve the browser, but it doesn't really need to use forms. So ditching forms would get rid of all these problems. You might need a command line to set the browser port, but that should be it.

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