From 456e1df6a33d24a287c9341af4f04226ba5019a2 Mon Sep 17 00:00:00 2001
From: Michael Schneider <mischneider1@gmail.com>
Date: Wed, 3 Apr 2019 18:04:01 -0700
Subject: [PATCH 1/2] Use instance lock for ASPrimitiveTraitCollection

---
 Source/ASDisplayNode+Layout.mm                   |  7 +++++--
 Source/Details/ASTraitCollection.h               | 10 ----------
 Source/Layout/ASLayoutSpec.mm                    | 12 +++++++++++-
 Source/Private/_ASCollectionGalleryLayoutItem.mm | 10 ++++++----
 4 files changed, 22 insertions(+), 17 deletions(-)

diff --git a/Source/ASDisplayNode+Layout.mm b/Source/ASDisplayNode+Layout.mm
index 66eb99879..592b18db9 100644
--- a/Source/ASDisplayNode+Layout.mm
+++ b/Source/ASDisplayNode+Layout.mm
@@ -128,15 +128,18 @@ - (ASLayout *)layoutThatFits:(ASSizeRange)constrainedSize parentSize:(CGSize)par
 
 - (ASPrimitiveTraitCollection)primitiveTraitCollection
 {
-  return _primitiveTraitCollection.load();
+  AS::MutexLocker l(__instanceLock__);
+  return _primitiveTraitCollection;
 }
 
 - (void)setPrimitiveTraitCollection:(ASPrimitiveTraitCollection)traitCollection
 {
-  if (ASPrimitiveTraitCollectionIsEqualToASPrimitiveTraitCollection(traitCollection, _primitiveTraitCollection.load()) == NO) {
+  AS::UniqueLock l(__instanceLock__);
+  if (ASPrimitiveTraitCollectionIsEqualToASPrimitiveTraitCollection(traitCollection, _primitiveTraitCollection) == NO) {
     _primitiveTraitCollection = traitCollection;
     ASDisplayNodeLogEvent(self, @"asyncTraitCollectionDidChange: %@", NSStringFromASPrimitiveTraitCollection(traitCollection));
 
+    l.unlock();
     [self asyncTraitCollectionDidChange];
   }
 }
diff --git a/Source/Details/ASTraitCollection.h b/Source/Details/ASTraitCollection.h
index 68244a660..17e1740c1 100644
--- a/Source/Details/ASTraitCollection.h
+++ b/Source/Details/ASTraitCollection.h
@@ -106,16 +106,6 @@ AS_EXTERN void ASTraitCollectionPropagateDown(id<ASLayoutElement> element, ASPri
 
 @end
 
-#define ASPrimitiveTraitCollectionDefaults \
-- (ASPrimitiveTraitCollection)primitiveTraitCollection\
-{\
-  return _primitiveTraitCollection.load();\
-}\
-- (void)setPrimitiveTraitCollection:(ASPrimitiveTraitCollection)traitCollection\
-{\
-  _primitiveTraitCollection = traitCollection;\
-}\
-
 #define ASLayoutElementCollectionTableSetTraitCollection(lock) \
 - (void)setPrimitiveTraitCollection:(ASPrimitiveTraitCollection)traitCollection\
 {\
diff --git a/Source/Layout/ASLayoutSpec.mm b/Source/Layout/ASLayoutSpec.mm
index 8da22d3d0..2bcb92787 100644
--- a/Source/Layout/ASLayoutSpec.mm
+++ b/Source/Layout/ASLayoutSpec.mm
@@ -146,7 +146,17 @@ - (ASTraitCollection *)asyncTraitCollection
   return [ASTraitCollection traitCollectionWithASPrimitiveTraitCollection:self.primitiveTraitCollection];
 }
 
-ASPrimitiveTraitCollectionDefaults
+- (ASPrimitiveTraitCollection)primitiveTraitCollection
+{
+  AS::MutexLocker l(__instanceLock__);
+  return _primitiveTraitCollection;
+}
+
+- (void)setPrimitiveTraitCollection:(ASPrimitiveTraitCollection)traitCollection
+{
+  AS::MutexLocker l(__instanceLock__);
+  _primitiveTraitCollection = traitCollection;
+}
 
 #pragma mark - ASLayoutElementStyleExtensibility
 
diff --git a/Source/Private/_ASCollectionGalleryLayoutItem.mm b/Source/Private/_ASCollectionGalleryLayoutItem.mm
index 573370299..e0faa1802 100644
--- a/Source/Private/_ASCollectionGalleryLayoutItem.mm
+++ b/Source/Private/_ASCollectionGalleryLayoutItem.mm
@@ -14,9 +14,12 @@
 #import <AsyncDisplayKit/ASLayoutElementStylePrivate.h>
 #import <AsyncDisplayKit/ASLayoutSpec.h>
 
-@implementation _ASGalleryLayoutItem {
-  std::atomic<ASPrimitiveTraitCollection> _primitiveTraitCollection;
-}
+@interface _ASGalleryLayoutItem ()
+@property ASPrimitiveTraitCollection primitiveTraitCollection;
+
+@end
+
+@implementation _ASGalleryLayoutItem
 
 @synthesize style;
 
@@ -33,7 +36,6 @@ - (instancetype)initWithItemSize:(CGSize)itemSize collectionElement:(ASCollectio
 }
 
 ASLayoutElementStyleExtensibilityForwarding
-ASPrimitiveTraitCollectionDefaults
 
 - (ASTraitCollection *)asyncTraitCollection
 {

From c8335b6a3a62aad815d1ac906a8e141a9114ce75 Mon Sep 17 00:00:00 2001
From: Michael Schneider <mischneider1@gmail.com>
Date: Wed, 3 Apr 2019 18:05:47 -0700
Subject: [PATCH 2/2] Remove the atomic

---
 Source/Private/ASDisplayNodeInternal.h | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/Source/Private/ASDisplayNodeInternal.h b/Source/Private/ASDisplayNodeInternal.h
index 879639f16..0cb4f1cc7 100644
--- a/Source/Private/ASDisplayNodeInternal.h
+++ b/Source/Private/ASDisplayNodeInternal.h
@@ -153,7 +153,7 @@ static constexpr CACornerMask kASCACornerAllCorners =
 
   // Layout support
   ASLayoutElementStyle *_style;
-  std::atomic<ASPrimitiveTraitCollection> _primitiveTraitCollection;
+  ASPrimitiveTraitCollection _primitiveTraitCollection;
 
   // Layout Spec
   ASLayoutSpecBlock _layoutSpecBlock;