Crash reduced to 13 lines of code

Somebody who knows how to debug FXRuby please help…  The following 13 lines of code will cause a seg fault immediately on Solaris/Ubuntu.  I can’t make it any simpler than this.   The code dies in the garbage collect mark code trying to get the focus window from FXApp (apparently because memory has become corrupted).

Thanks,

Ryan

require 'rubygems'

require 'thread'

require 'fox16'

include Fox

Thread.new do

  loop do

    GC.start

  end

end

application = FXApp.new("NA", "NA")

application.create

FXMessageBox.warning(FXApp.instance, MBOX_OK, 'Warning!', 'Are you sure?')

application.run  

I posted the patch to rubyforge here: http://rubyforge.org/tracker/index.php?func=detail&aid=24898&group_id=300&atid=1223

Lyle if you could release a new version of FXRuby with this fix, I would really appreciate it.

Here is the summary so people don’t have to follow the link:

Here the fix, the issue turned out to be very complicated related

to how ruby handles the stack frames of its threads.  In summary,

you can't access stack variables between threads.

FXMessageBox::warning creates the FXMessageBox on the stack.

If the Garbage Collector running in another threads context trys

to access the FXMessageBox, it blows up because the stack values

are no longer in context.  Below is the fix.

Add this method to FXRbApp.cpp:

FXWindow *FXApp::getFocusWindow() const {

  FXWindow *result=getActiveWindow();

  VALUE value=FXRbGetRubyObj(result,true);

  if(!NIL_P(value)){

    if(result){

      while(result->getFocus()){

        result=result->getFocus();

        }

      }

    return result;

    }

  return NULL;

  }

Update markfuncs.cpp FXRbWindow::markfunc with this change:

Was:

while(child!=NULL){

Is:

while((child!=NULL) && (!(NIL_P(FXRbGetRubyObj(child,

true))))){

Thanks,

Ryan

Somebody who knows how to debug FXRuby please help…  The following 13 lines of code will cause a seg fault immediately on Solaris/Ubuntu.  I can’t make it any simpler than this.   The code dies in the garbage collect mark code trying to get the focus window from FXApp (apparently because memory has become corrupted).

Thanks,

Ryan

require 'rubygems'

require 'thread'

require 'fox16'

include Fox

Thread.new do

  loop do

    GC.start

  end

end

application = FXApp.new("NA", "NA")

application.create

FXMessageBox.warning(FXApp.instance, MBOX_OK, 'Warning!', 'Are you sure?')