None of the posted answers solved the problem for me. But the reason for this is the following: Xcode 6 creates constraints based on relative margins by default. Those are only available on iOS 8.0 and newer. You get these warnings when your deployment target is set to iOS 7.0 or lower.
The way I fixed the warning:
- Click the warning in Xcode
- Attribute inspector will open the constraint
- Search for item that has margin (see screenshot)
- Turn off Relative to margin option
与恶龙缠斗过久,自身亦成为恶龙;凝视深渊过久,深渊将回以凝视…