Hi:
I'm using Xcode 7.0, OSX 10.10.5, and on one project IB has crashed over 20 times today. It happens as I am adjusting constraints.
Each time the error is "internal error. Setting empty vector for variable UILabel", but the label isn't always the same one.
The error is not exactly reproducible; after restarting I can do the same action and continue for a few minutes before the next crash...
The storyboard is very simple. The view I'm working on has only 6 labels and one button, and stack views.
The crashes started around the time I started using stack views and size classes.
I filed a bug report (22858326), but it would be great if anyone had any advice for avoiding this error.
Thanks.