What this warning means is that apparently the "Automatic Preferred Max Layout Width" is only available on iOS 8 and newer and your app (or at least the storyboard) supports earlier versions of iOS. If you try to open the app on an iOS 7 or earlier device, it won't work correctly. There are two ways you could fix this:
- Move your minimum supported version up to at least iOS 8
- Use a different setting for that label (perhaps try to set the layout width yourself in Interface Builder?)
"Automatic Preferred Max Layout Width" is disabled and width is fixed.
The problem is with number of lines, >1 get warning.