Feedback node crashing bug

[ammouri]

I have posted on the NI forum (here) but didn't get any response sine 5 days.

I have came across a nasty bug that caused Labview 2010 SP1 (Running Win 7 Ultimate x64 bit) to crash without any warning.

To replicate the bug do the following:

1. Add a numeric control and another indicator to the front panel
   
2. Switch to block diagram and add a feed back node
   
3. Connect the initializer terminal of the feed back node to the output of the control
   
4. Now do ANY of the following to cause the bug:
   
   • Press the run button (which is broken due to not connecting the input of the feed back node) it will turn to a normal run without displaying the error
     
   • Do an extra action and undo it, the run button will turn from list error normal
     

• So far the Vi can be saved normally. Now connect the output of the feed back node to the indicator and try any of the followings:
  
  • Save the VI
    
  • Close the VI
    
  • Create a new project and select to add the VI to the project
    

  This will cause Labview to crash without any notice!

When you are at step 4, the bug is there but harmless. Once you combine it with step 5 (connect to indicator), the bug is active and cause crashing. I have attached a snapshot of how the Front panel/block diagram look like before saving (since it can't be saved). Notice how the run button is enabled although the input of the feedback node is not connected.

I have tried to replicate the error on Labview 2009 but couldn't.

[asbo]

I could reproduce this in LV2010 SP1 on Windows 7 Professional x64. I could not reproduce it in LV2009f3 or LV2011.