iOS 8.3 crashes when installing constraints on views.

file

//A multiplier of 0 or a nil second item together with a location for the first attribute creates 
//an illegal constraint of a location equal to a constant. Location attributes must be specified in 
//pairs.
//                                       OR
//[NSLayoutConstraint constraintWithItem:attribute:relatedBy:toItem:attribute:multiplier:constant:]: 
//A multiplier of 0 or a nil second item together with a location for the first attribute creates an illegal 
//constraint of a location equal to a constant. Location attributes must be specified in pairs'

//Use
NSLayoutConstraint *constraint = [NSLayoutConstraint constraintWithItem:self.view1
                                                          attribute:NSLayoutAttributeRight
                                                          relatedBy:NSLayoutRelationEqual
							  toItem:self.view2
							   attribute:NSLayoutAttributeLeft
							  multiplier:1
							  constant:0];