From 1754aed4dcfeda4e16b700e7b8095c73169c7cec Mon Sep 17 00:00:00 2001
From: Robert Payne <robertpayne@me.com>
Date: Mon, 5 Aug 2019 18:16:37 +1200
Subject: [PATCH] Revert #574

---
 Source/LayoutConstraint.swift | 33 +++++++--------------------------
 1 file changed, 7 insertions(+), 26 deletions(-)

diff --git a/Source/LayoutConstraint.swift b/Source/LayoutConstraint.swift
index bf8ef3f..5425ea8 100644
--- a/Source/LayoutConstraint.swift
+++ b/Source/LayoutConstraint.swift
@@ -44,36 +44,17 @@ public class LayoutConstraint : NSLayoutConstraint {
 }
 
 internal func ==(lhs: LayoutConstraint, rhs: LayoutConstraint) -> Bool {
-    #if os(OSX)
-    // ensure first anchor items match
-    guard let item1 = lhs.firstAnchor.item,
-          let item2 = rhs.firstAnchor.item,
-          item1 === item2 else {
-        return false
-    }
-
-    // ensure second anchor items match
-    guard ((lhs.secondAnchor?.item == nil && rhs.secondAnchor?.item == nil) ||
-           (lhs.secondAnchor?.item === rhs.secondAnchor?.item)) else {
-        return false
-    }
-    #else
-    guard lhs.firstAnchor == rhs.firstAnchor else {
-        return false
-    }
-    guard ((lhs.secondAnchor == nil && rhs.secondAnchor == nil) ||
-           (lhs.secondAnchor! == rhs.secondAnchor!)) else {
-        return false
-    }
-    #endif
-
-
-    // ensure attributes, relation, priorty and multiplier match
+    // If firstItem or secondItem on either constraint has a dangling pointer
+    // this comparison can cause a crash. The solution for this is to ensure
+    // your layout code hold strong references to things like Views, LayoutGuides
+    // and LayoutAnchors as SnapKit will not keep strong references to any of these.
     guard lhs.firstAttribute == rhs.firstAttribute &&
           lhs.secondAttribute == rhs.secondAttribute &&
           lhs.relation == rhs.relation &&
           lhs.priority == rhs.priority &&
-          lhs.multiplier == rhs.multiplier else {
+          lhs.multiplier == rhs.multiplier &&
+          lhs.secondItem === rhs.secondItem &&
+          lhs.firstItem === rhs.firstItem else {
         return false
     }
     return true