This warning can be annoying and happens as of Xcode 6.1.1. The main problem is that you can not easily find the referenced constraint by clicking on the warning. I guess this is a bug and will get fixed sooner or later.
However, in the meantime you can use this little workaround:
Reveal in Log
๐จ... snip ...
/Devel/MyCrippledAppNG/MyCrippledApp/Main_iPad.storyboard:Dlb-cb-nWC: warning: Constraint referencing items turned off in current configuration. Turn off this constraint in the current configuration.
/Devel/MyCrippledAppNG/MyCrippledApp/Main_iPad.storyboard:6Ze-mO-v5N: warning: Constraint referencing items turned off in current configuration. Turn off this constraint in the current configuration.
/Devel/MyCrippledAppNG/MyCrippledApp/Main_iPad.storyboard:9av-xw-u1o: warning: Constraint referencing items turned off in current configuration. Turn off this constraint in the current configuration.
/Devel/MyCrippledAppNG/MyCrippledApp/Main_iPad.storyboard:RPt-Uf-vaZ: warning: Constraint referencing items turned off in current configuration. Turn off this constraint in the current configuration.
/Devel/MyCrippledAppNG/MyCrippledApp/Main_iPad.storyboard:Rnc-4M-7jV: warning: Constraint referencing items turned off in current configuration. Turn off this constraint in the current configuration.
/Devel/MyCrippledAppNG/MyCrippledApp/Main_iPad.storyboard:epJ-D9-KEF: warning: Constraint referencing items turned off in current configuration. Turn off this constraint in the current configuration.
/Devel/MyCrippledAppNG/MyCrippledApp/Main_iPad.storyboard:4HC-Gu-01w: warning: Constraint referencing items turned off in current configuration. Turn off this constraint in the current configuration.
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Note that for Xcode of 5/2016, annoyingly you have to quit and restart Xcode to clear this warning in some cases.
Note that confusingly, the same error can be caused by an unrelated problem (this appears to be an Apple bug or poor use of error language): if you have IBInspectable
items, and happen to rename them in your Swift files. Xcode does not delete the old-name UserDefinedRuntimeAttributes for you. Simply click to "Identity Inspector" (item 3 on right panel) and delete the dud items.