Storyboard missing constraint every time restart Xcode

Question

Using auto layout in storyboard, I add some constraints on a UILabel and no warnings, then I restart Xcode it would show me the warning like the picture, I fixed the warning, but when I restart Xcode the same warning appears again. Now there are about 20 same warnings in my storyboard, I have to fix it every time I restart Xcode.

Edit for detail

1. A UILabel with width is 0 and constraints is like this

2. When I restart Xcode, then it change to :

3. And show me the warning:

4. Then I have to click the waring button and 'Update Frame' to fix it

Answer 1

After a simple research I found that this bug could easily be reproduced and doesn't depends on git, storyboard permissions etc. To reproduce it you could just create UILabel without text and set its width to 0. Moreover you don't need to add some additional views, just only one UILabel. To conclude, I think you've found a bug in storyboard, and unfortunately I haven't found any workaround. Probably you should report it https://bugreport.apple.com.