How can I avoid specifying potentially conflicting constraints - swift

Question

I am trying to create all of my views in my UICollectionViewCell programatically. The views currently lay out correctly.
I have a vertical stackView that contains two UILabels and a UIImageView.
The views do not have a fixed content size and are all variable.
If you see in my code, I am setting the leading and trailing constraints of my UIStackView with a constant of 8.0 from the safeAreaLayoutGuide. Because of this, I have to set the widthAnchor to be -16.0 (otherwise the cell does not lay out correctly). Is there a way I can avoid specifying this in two places? For example, if I set the leading to be 14.0 points from the leading, then I will have to make sure I remember to change my width to be -20.0, otherwise the contents will spill over.
override func updateConstraints() {
/// Check if views already have constraints
if !viewsHaveConstraints {
viewsHaveConstraints = true
/*
Here I set the hugging and compression priority for the 3 views in the UIStackView
*/
let margins = safeAreaLayoutGuide
/* Set vstackView constraints */
/// vStackView width anchor equal to width of margin less constant
vStackView.widthAnchor.constraint(equalTo: margins.widthAnchor, constant: -16.0).isActive = true
/// vStackView leading anchor constraint
vStackView.leadingAnchor.constraint(equalTo: margins.leadingAnchor, constant: 8.0).isActive = true
/// vStackView trailing anchor constraint
vStackView.trailingAnchor.constraint(equalTo: margins.trailingAnchor, constant: 8.0).isActive = true
vStackView.heightAnchor.constraint(equalTo: margins.heightAnchor).isActive = true
}
super.updateConstraints()
}