Narrowed Crash to Running GC in a separate thread while MessageBox is shown

Here is an updated version of the code that causes the crash.  Using ddd I narrowed the crash to the garbage collector running while the MessageBox is shown.  This simpler example simply calls GC.start in a separate thread, and will crash it every time on the second occurance of the GC running.  Something is apparently getting garbage collected that shouldn’t be.

Ryan

 

require 'rubygems'

require 'fox16'

include Fox

 

require 'thread'

 

class CrashMe < FXMainWindow

 

  def initialize (app, title)

    # Call the base class initializer first

    super(app, title)

 

    # Create a Vertical Frame for the application's contents

    @frame = FXVerticalFrame.new(self, LAYOUT_FILL_X|LAYOUT_FILL_Y|FRAME_SUNKEN)

   

    button = FXButton.new(@frame, "Press Me").connect(SEL_COMMAND, method(:handle_button_1))

 

  end

 

  def handle_button_1 (sender, sel, data)

    Thread.new do

      loop_count = 1

      loop do

        STDOUT.puts "Running GC #{loop_count}"

        GC.start

        loop_count += 1

      end

    end

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

  end

 

  def run_gc (sender, sel, data)

    GC.start

  end

 

  def self.run

    # Make application

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

 

    # Make window

    window = self.new(application, "Title")

    window.show

   

    # Create the application windows

    application.create

   

    # Run the application

    application.run   

  end # def self.run

 

end # class CrashMe

 

CrashMe.run

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