Standardize "extern" decls on AS_EXTERN

CHANGELOG.md

@@ -7,6 +7,7 @@
 - Add new protocol `ASLocking` that extends `NSLocking` with `tryLock`, and allows taking multiple locks safely. [Adlai Holler](https://github.com/Adlai-Holler)
 - Make the main thread ivar deallocation system available to other classes. Plus a little optimization. See `ASMainThreadDeallocation.h`. [Adlai Holler](https://github.com/Adlai-Holler) [#959](https://github.com/TextureGroup/Texture/pull/959)
 - Reduce usage of autorelease pools. [Adlai Holler](https://github.com/Adlai-Holler) [#968](https://github.com/TextureGroup/Texture/pull/968)
+- Clean up C-function `extern` decorators. [Adlai Holler](https://github.com/Adlai-Holler)
 
 ## 2.7
 - Fix pager node for interface coalescing. [Max Wang](https://github.com/wsdwsd0829) [#877](https://github.com/TextureGroup/Texture/pull/877)

Source/ASConfigurationInternal.h

@@ -17,15 +17,14 @@
 #import <AsyncDisplayKit/ASConfiguration.h>
 
 NS_ASSUME_NONNULL_BEGIN
-ASDISPLAYNODE_EXTERN_C_BEGIN
 
 /**
  * Quickly check if an experiment is enabled and notify the delegate
  * that it's been activated.
  *
  * The delegate will be notified asynchronously.
  */
-BOOL ASActivateExperimentalFeature(ASExperimentalFeatures option);
+AS_EXTERN BOOL ASActivateExperimentalFeature(ASExperimentalFeatures option);
 
 AS_SUBCLASSING_RESTRICTED
 @interface ASConfigurationManager : NSObject
@@ -38,4 +37,3 @@ AS_SUBCLASSING_RESTRICTED
 @end
 
 NS_ASSUME_NONNULL_END
-ASDISPLAYNODE_EXTERN_C_END

Source/ASContextTransitioning.h

@@ -22,8 +22,8 @@
 
 NS_ASSUME_NONNULL_BEGIN
 
-extern NSString * const ASTransitionContextFromLayoutKey;
-extern NSString * const ASTransitionContextToLayoutKey;
+AS_EXTERN NSString * const ASTransitionContextFromLayoutKey;
+AS_EXTERN NSString * const ASTransitionContextToLayoutKey;
 
 @protocol ASContextTransitioning <NSObject>
 

Source/ASDisplayNode+Beta.h

@@ -27,10 +27,8 @@
 
 NS_ASSUME_NONNULL_BEGIN
 
-ASDISPLAYNODE_EXTERN_C_BEGIN
-void ASPerformBlockOnMainThread(void (^block)(void));
-void ASPerformBlockOnBackgroundThread(void (^block)(void)); // DISPATCH_QUEUE_PRIORITY_DEFAULT
-ASDISPLAYNODE_EXTERN_C_END
+AS_EXTERN void ASPerformBlockOnMainThread(void (^block)(void));
+AS_EXTERN void ASPerformBlockOnBackgroundThread(void (^block)(void)); // DISPATCH_QUEUE_PRIORITY_DEFAULT
 
 #if ASEVENTLOG_ENABLE
   #define ASDisplayNodeLogEvent(node, ...) [node.eventLog logEventWithBacktrace:(AS_SAVE_EVENT_BACKTRACES ? [NSThread callStackSymbols] : nil) format:__VA_ARGS__]
@@ -167,7 +165,7 @@ typedef struct {
 
 #if YOGA
 
-extern void ASDisplayNodePerformBlockOnEveryYogaChild(ASDisplayNode * _Nullable node, void(^block)(ASDisplayNode *node));
+AS_EXTERN void ASDisplayNodePerformBlockOnEveryYogaChild(ASDisplayNode * _Nullable node, void(^block)(ASDisplayNode *node));
 
 @interface ASDisplayNode (Yoga)
 

Source/ASDisplayNode.h

@@ -110,7 +110,7 @@ typedef NS_ENUM(NSInteger, ASCornerRoundingType) {
 /**
  * Default drawing priority for display node
  */
-extern NSInteger const ASDefaultDrawingPriority;
+AS_EXTERN NSInteger const ASDefaultDrawingPriority;
 
 /**
  * An `ASDisplayNode` is an abstraction over `UIView` and `CALayer` that allows you to perform calculations about a view

Source/ASDisplayNodeExtras.h

@@ -36,10 +36,8 @@
 
 NS_ASSUME_NONNULL_BEGIN
 
-ASDISPLAYNODE_EXTERN_C_BEGIN
-
 /// For deallocation of objects on the main thread across multiple run loops.
-extern void ASPerformMainThreadDeallocation(id _Nullable __strong * _Nonnull objectPtr);
+AS_EXTERN void ASPerformMainThreadDeallocation(id _Nullable __strong * _Nonnull objectPtr);
 
 // Because inline methods can't be extern'd and need to be part of the translation unit of code
 // that compiles with them to actually inline, we both declare and define these in the header.
@@ -111,62 +109,62 @@ __unused static NSString *NSStringFromASInterfaceStateChange(ASInterfaceState ol
 /**
  Returns the appropriate interface state for a given ASDisplayNode and window
  */
-extern ASInterfaceState ASInterfaceStateForDisplayNode(ASDisplayNode *displayNode, UIWindow *window) AS_WARN_UNUSED_RESULT;
+AS_EXTERN ASInterfaceState ASInterfaceStateForDisplayNode(ASDisplayNode *displayNode, UIWindow *window) AS_WARN_UNUSED_RESULT;
 
 /**
  Given a layer, returns the associated display node, if any.
  */
-extern ASDisplayNode * _Nullable ASLayerToDisplayNode(CALayer * _Nullable layer) AS_WARN_UNUSED_RESULT;
+AS_EXTERN ASDisplayNode * _Nullable ASLayerToDisplayNode(CALayer * _Nullable layer) AS_WARN_UNUSED_RESULT;
 
 /**
  Given a view, returns the associated display node, if any.
  */
-extern ASDisplayNode * _Nullable ASViewToDisplayNode(UIView * _Nullable view) AS_WARN_UNUSED_RESULT;
+AS_EXTERN ASDisplayNode * _Nullable ASViewToDisplayNode(UIView * _Nullable view) AS_WARN_UNUSED_RESULT;
 
 /**
  Given a node, returns the root of the node hierarchy (where supernode == nil)
  */
-extern ASDisplayNode *ASDisplayNodeUltimateParentOfNode(ASDisplayNode *node) AS_WARN_UNUSED_RESULT;
+AS_EXTERN ASDisplayNode *ASDisplayNodeUltimateParentOfNode(ASDisplayNode *node) AS_WARN_UNUSED_RESULT;
 
 /**
  If traverseSublayers == YES, this function will walk the layer hierarchy, spanning discontinuous sections of the node hierarchy\
  (e.g. the layers of UIKit intermediate views in UIViewControllers, UITableView, UICollectionView).
  In the event that a node's backing layer is not created yet, the function will only walk the direct subnodes instead
  of forcing the layer hierarchy to be created.
  */
-extern void ASDisplayNodePerformBlockOnEveryNode(CALayer * _Nullable layer, ASDisplayNode * _Nullable node, BOOL traverseSublayers, void(^block)(ASDisplayNode *node));
+AS_EXTERN void ASDisplayNodePerformBlockOnEveryNode(CALayer * _Nullable layer, ASDisplayNode * _Nullable node, BOOL traverseSublayers, void(^block)(ASDisplayNode *node));
 
 /**
  This function will walk the node hierarchy in a breadth first fashion. It does run the block on the node provided
  directly to the function call.  It does NOT traverse sublayers.
  */
-extern void ASDisplayNodePerformBlockOnEveryNodeBFS(ASDisplayNode *node, void(^block)(ASDisplayNode *node));
+AS_EXTERN void ASDisplayNodePerformBlockOnEveryNodeBFS(ASDisplayNode *node, void(^block)(ASDisplayNode *node));
 
 /**
  Identical to ASDisplayNodePerformBlockOnEveryNode, except it does not run the block on the
  node provided directly to the function call - only on all descendants.
  */
-extern void ASDisplayNodePerformBlockOnEverySubnode(ASDisplayNode *node, BOOL traverseSublayers, void(^block)(ASDisplayNode *node));
+AS_EXTERN void ASDisplayNodePerformBlockOnEverySubnode(ASDisplayNode *node, BOOL traverseSublayers, void(^block)(ASDisplayNode *node));
 
 /**
  Given a display node, traverses up the layer tree hierarchy, returning the first display node that passes block.
  */
-extern ASDisplayNode * _Nullable ASDisplayNodeFindFirstSupernode(ASDisplayNode * _Nullable node, BOOL (^block)(ASDisplayNode *node)) AS_WARN_UNUSED_RESULT ASDISPLAYNODE_DEPRECATED_MSG("Use the `supernodes` property instead.");
+AS_EXTERN ASDisplayNode * _Nullable ASDisplayNodeFindFirstSupernode(ASDisplayNode * _Nullable node, BOOL (^block)(ASDisplayNode *node)) AS_WARN_UNUSED_RESULT ASDISPLAYNODE_DEPRECATED_MSG("Use the `supernodes` property instead.");
 
 /**
  Given a display node, traverses up the layer tree hierarchy, returning the first display node of kind class.
  */
-extern __kindof ASDisplayNode * _Nullable ASDisplayNodeFindFirstSupernodeOfClass(ASDisplayNode *start, Class c) AS_WARN_UNUSED_RESULT  ASDISPLAYNODE_DEPRECATED_MSG("Use the `supernodeOfClass:includingSelf:` method instead.");
+AS_EXTERN __kindof ASDisplayNode * _Nullable ASDisplayNodeFindFirstSupernodeOfClass(ASDisplayNode *start, Class c) AS_WARN_UNUSED_RESULT  ASDISPLAYNODE_DEPRECATED_MSG("Use the `supernodeOfClass:includingSelf:` method instead.");
 
 /**
  * Given a layer, find the window it lives in, if any.
  */
-extern UIWindow * _Nullable ASFindWindowOfLayer(CALayer *layer) AS_WARN_UNUSED_RESULT;
+AS_EXTERN UIWindow * _Nullable ASFindWindowOfLayer(CALayer *layer) AS_WARN_UNUSED_RESULT;
 
 /**
  * Given a layer, find the closest view it lives in, if any.
  */
-extern UIView * _Nullable ASFindClosestViewOfLayer(CALayer *layer) AS_WARN_UNUSED_RESULT;
+AS_EXTERN UIView * _Nullable ASFindClosestViewOfLayer(CALayer *layer) AS_WARN_UNUSED_RESULT;
 
 /**
  * Given two nodes, finds their most immediate common parent.  Used for geometry conversion methods.
@@ -176,50 +174,48 @@ extern UIView * _Nullable ASFindClosestViewOfLayer(CALayer *layer) AS_WARN_UNUSE
  * undefined and undocumented behavior of UIKit in ASDisplayNode, this operation is defined to be incorrect in all
  * circumstances and must be fixed wherever encountered.
  */
-extern ASDisplayNode * _Nullable ASDisplayNodeFindClosestCommonAncestor(ASDisplayNode *node1, ASDisplayNode *node2) AS_WARN_UNUSED_RESULT;
+AS_EXTERN ASDisplayNode * _Nullable ASDisplayNodeFindClosestCommonAncestor(ASDisplayNode *node1, ASDisplayNode *node2) AS_WARN_UNUSED_RESULT;
 
 /**
  Given a display node, collects all descendants. This is a specialization of ASCollectContainer() that walks the Core Animation layer tree as opposed to the display node tree, thus supporting non-continues display node hierarchies.
  */
-extern NSArray<ASDisplayNode *> *ASCollectDisplayNodes(ASDisplayNode *node) AS_WARN_UNUSED_RESULT;
+AS_EXTERN NSArray<ASDisplayNode *> *ASCollectDisplayNodes(ASDisplayNode *node) AS_WARN_UNUSED_RESULT;
 
 /**
  Given a display node, traverses down the node hierarchy, returning all the display nodes that pass the block.
  */
-extern NSArray<ASDisplayNode *> *ASDisplayNodeFindAllSubnodes(ASDisplayNode *start, BOOL (^block)(ASDisplayNode *node)) AS_WARN_UNUSED_RESULT;
+AS_EXTERN NSArray<ASDisplayNode *> *ASDisplayNodeFindAllSubnodes(ASDisplayNode *start, BOOL (^block)(ASDisplayNode *node)) AS_WARN_UNUSED_RESULT;
 
 /**
  Given a display node, traverses down the node hierarchy, returning all the display nodes of kind class.
  */
-extern NSArray<__kindof ASDisplayNode *> *ASDisplayNodeFindAllSubnodesOfClass(ASDisplayNode *start, Class c) AS_WARN_UNUSED_RESULT;
+AS_EXTERN NSArray<__kindof ASDisplayNode *> *ASDisplayNodeFindAllSubnodesOfClass(ASDisplayNode *start, Class c) AS_WARN_UNUSED_RESULT;
 
 /**
  Given a display node, traverses down the node hierarchy, returning the depth-first display node, including the start node that pass the block.
  */
-extern __kindof ASDisplayNode * _Nullable ASDisplayNodeFindFirstNode(ASDisplayNode *start, BOOL (^block)(ASDisplayNode *node)) AS_WARN_UNUSED_RESULT;
+AS_EXTERN __kindof ASDisplayNode * _Nullable ASDisplayNodeFindFirstNode(ASDisplayNode *start, BOOL (^block)(ASDisplayNode *node)) AS_WARN_UNUSED_RESULT;
 
 /**
  Given a display node, traverses down the node hierarchy, returning the depth-first display node, excluding the start node, that pass the block
  */
-extern __kindof ASDisplayNode * _Nullable ASDisplayNodeFindFirstSubnode(ASDisplayNode *start, BOOL (^block)(ASDisplayNode *node)) AS_WARN_UNUSED_RESULT;
+AS_EXTERN __kindof ASDisplayNode * _Nullable ASDisplayNodeFindFirstSubnode(ASDisplayNode *start, BOOL (^block)(ASDisplayNode *node)) AS_WARN_UNUSED_RESULT;
 
 /**
  Given a display node, traverses down the node hierarchy, returning the depth-first display node of kind class.
  */
-extern __kindof ASDisplayNode * _Nullable ASDisplayNodeFindFirstSubnodeOfClass(ASDisplayNode *start, Class c) AS_WARN_UNUSED_RESULT;
+AS_EXTERN __kindof ASDisplayNode * _Nullable ASDisplayNodeFindFirstSubnodeOfClass(ASDisplayNode *start, Class c) AS_WARN_UNUSED_RESULT;
 
-extern UIColor *ASDisplayNodeDefaultPlaceholderColor(void) AS_WARN_UNUSED_RESULT;
-extern UIColor *ASDisplayNodeDefaultTintColor(void) AS_WARN_UNUSED_RESULT;
+AS_EXTERN UIColor *ASDisplayNodeDefaultPlaceholderColor(void) AS_WARN_UNUSED_RESULT;
+AS_EXTERN UIColor *ASDisplayNodeDefaultTintColor(void) AS_WARN_UNUSED_RESULT;
 
 /**
  Disable willAppear / didAppear / didDisappear notifications for a sub-hierarchy, then re-enable when done. Nested calls are supported.
  */
-extern void ASDisplayNodeDisableHierarchyNotifications(ASDisplayNode *node);
-extern void ASDisplayNodeEnableHierarchyNotifications(ASDisplayNode *node);
+AS_EXTERN void ASDisplayNodeDisableHierarchyNotifications(ASDisplayNode *node);
+AS_EXTERN void ASDisplayNodeEnableHierarchyNotifications(ASDisplayNode *node);
 
 // Not to be called directly.
-extern void _ASSetDebugNames(Class owningClass, NSString *names, ASDisplayNode *object, ...);
-
-ASDISPLAYNODE_EXTERN_C_END
+AS_EXTERN void _ASSetDebugNames(Class owningClass, NSString *names, ASDisplayNode *object, ...);
 
 NS_ASSUME_NONNULL_END

Source/ASDisplayNodeExtras.mm

@@ -23,7 +23,7 @@
 #import <queue>
 #import <AsyncDisplayKit/ASRunLoopQueue.h>
 
-extern void ASPerformMainThreadDeallocation(id _Nullable __strong * _Nonnull objectPtr) {
+AS_EXTERN void ASPerformMainThreadDeallocation(id _Nullable __strong * _Nonnull objectPtr) {
   /**
    * UIKit components must be deallocated on the main thread. We use this shared
    * run loop queue to gradually deallocate them across many turns of the main run loop.
@@ -48,7 +48,7 @@ extern void ASPerformMainThreadDeallocation(id _Nullable __strong * _Nonnull obj
   }
 }
 
-extern void _ASSetDebugNames(Class _Nonnull owningClass, NSString * _Nonnull names, ASDisplayNode * _Nullable object, ...)
+AS_EXTERN void _ASSetDebugNames(Class _Nonnull owningClass, NSString * _Nonnull names, ASDisplayNode * _Nullable object, ...)
 {
   NSString *owningClassName = NSStringFromClass(owningClass);
   NSArray *nameArray = [names componentsSeparatedByString:@", "];
@@ -66,7 +66,7 @@ extern void _ASSetDebugNames(Class _Nonnull owningClass, NSString * _Nonnull nam
   va_end(args);
 }
 
-extern ASInterfaceState ASInterfaceStateForDisplayNode(ASDisplayNode *displayNode, UIWindow *window)
+AS_EXTERN ASInterfaceState ASInterfaceStateForDisplayNode(ASDisplayNode *displayNode, UIWindow *window)
 {
     ASDisplayNodeCAssert(![displayNode isLayerBacked], @"displayNode must not be layer backed as it may have a nil window");
     if (displayNode && [displayNode supportsRangeManagedInterfaceState]) {
@@ -81,17 +81,17 @@ extern ASInterfaceState ASInterfaceStateForDisplayNode(ASDisplayNode *displayNod
     }
 }
 
-extern ASDisplayNode *ASLayerToDisplayNode(CALayer *layer)
+AS_EXTERN ASDisplayNode *ASLayerToDisplayNode(CALayer *layer)
 {
   return layer.asyncdisplaykit_node;
 }
 
-extern ASDisplayNode *ASViewToDisplayNode(UIView *view)
+AS_EXTERN ASDisplayNode *ASViewToDisplayNode(UIView *view)
 {
   return view.asyncdisplaykit_node;
 }
 
-extern void ASDisplayNodePerformBlockOnEveryNode(CALayer * _Nullable layer, ASDisplayNode * _Nullable node, BOOL traverseSublayers, void(^block)(ASDisplayNode *node))
+AS_EXTERN void ASDisplayNodePerformBlockOnEveryNode(CALayer * _Nullable layer, ASDisplayNode * _Nullable node, BOOL traverseSublayers, void(^block)(ASDisplayNode *node))
 {
   if (!node) {
     ASDisplayNodeCAssertNotNil(layer, @"Cannot recursively perform with nil node and nil layer");
@@ -119,7 +119,7 @@ extern void ASDisplayNodePerformBlockOnEveryNode(CALayer * _Nullable layer, ASDi
   }
 }
 
-extern void ASDisplayNodePerformBlockOnEveryNodeBFS(ASDisplayNode *node, void(^block)(ASDisplayNode *node))
+AS_EXTERN void ASDisplayNodePerformBlockOnEveryNodeBFS(ASDisplayNode *node, void(^block)(ASDisplayNode *node))
 {
   // Queue used to keep track of subnodes while traversing this layout in a BFS fashion.
   std::queue<ASDisplayNode *> queue;
@@ -138,7 +138,7 @@ extern void ASDisplayNodePerformBlockOnEveryNodeBFS(ASDisplayNode *node, void(^b
   }
 }
 
-extern void ASDisplayNodePerformBlockOnEverySubnode(ASDisplayNode *node, BOOL traverseSublayers, void(^block)(ASDisplayNode *node))
+AS_EXTERN void ASDisplayNodePerformBlockOnEverySubnode(ASDisplayNode *node, BOOL traverseSublayers, void(^block)(ASDisplayNode *node))
 {
   for (ASDisplayNode *subnode in node.subnodes) {
     ASDisplayNodePerformBlockOnEveryNode(nil, subnode, YES, block);
@@ -176,7 +176,7 @@ static void _ASCollectDisplayNodes(NSMutableArray *array, CALayer *layer)
     _ASCollectDisplayNodes(array, sublayer);
 }
 
-extern NSArray<ASDisplayNode *> *ASCollectDisplayNodes(ASDisplayNode *node)
+AS_EXTERN NSArray<ASDisplayNode *> *ASCollectDisplayNodes(ASDisplayNode *node)
 {
   NSMutableArray *list = [[NSMutableArray alloc] init];
   for (CALayer *sublayer in node.layer.sublayers) {
@@ -201,14 +201,14 @@ static void _ASDisplayNodeFindAllSubnodes(NSMutableArray *array, ASDisplayNode *
   }
 }
 
-extern NSArray<ASDisplayNode *> *ASDisplayNodeFindAllSubnodes(ASDisplayNode *start, BOOL (^block)(ASDisplayNode *node))
+AS_EXTERN NSArray<ASDisplayNode *> *ASDisplayNodeFindAllSubnodes(ASDisplayNode *start, BOOL (^block)(ASDisplayNode *node))
 {
   NSMutableArray *list = [[NSMutableArray alloc] init];
   _ASDisplayNodeFindAllSubnodes(list, start, block);
   return list;
 }
 
-extern NSArray<__kindof ASDisplayNode *> *ASDisplayNodeFindAllSubnodesOfClass(ASDisplayNode *start, Class c)
+AS_EXTERN NSArray<__kindof ASDisplayNode *> *ASDisplayNodeFindAllSubnodesOfClass(ASDisplayNode *start, Class c)
 {
   return ASDisplayNodeFindAllSubnodes(start, ^(ASDisplayNode *n) {
     return [n isKindOfClass:c];
@@ -232,17 +232,17 @@ static void _ASDisplayNodeFindAllSubnodes(NSMutableArray *array, ASDisplayNode *
   return nil;
 }
 
-extern __kindof ASDisplayNode *ASDisplayNodeFindFirstNode(ASDisplayNode *startNode, BOOL (^block)(ASDisplayNode *node))
+AS_EXTERN __kindof ASDisplayNode *ASDisplayNodeFindFirstNode(ASDisplayNode *startNode, BOOL (^block)(ASDisplayNode *node))
 {
   return _ASDisplayNodeFindFirstNode(startNode, YES, block);
 }
 
-extern __kindof ASDisplayNode *ASDisplayNodeFindFirstSubnode(ASDisplayNode *startNode, BOOL (^block)(ASDisplayNode *node))
+AS_EXTERN __kindof ASDisplayNode *ASDisplayNodeFindFirstSubnode(ASDisplayNode *startNode, BOOL (^block)(ASDisplayNode *node))
 {
   return _ASDisplayNodeFindFirstNode(startNode, NO, block);
 }
 
-extern __kindof ASDisplayNode *ASDisplayNodeFindFirstSubnodeOfClass(ASDisplayNode *start, Class c)
+AS_EXTERN __kindof ASDisplayNode *ASDisplayNodeFindFirstSubnodeOfClass(ASDisplayNode *start, Class c)
 {
   return ASDisplayNodeFindFirstSubnode(start, ^(ASDisplayNode *n) {
     return [n isKindOfClass:c];
@@ -262,7 +262,7 @@ static inline BOOL _ASDisplayNodeIsAncestorOfDisplayNode(ASDisplayNode *possible
   return NO;
 }
 
-extern UIWindow * _Nullable ASFindWindowOfLayer(CALayer *layer)
+AS_EXTERN UIWindow * _Nullable ASFindWindowOfLayer(CALayer *layer)
 {
   UIView *view = ASFindClosestViewOfLayer(layer);
   if (UIWindow *window = ASDynamicCast(view, UIWindow)) {
@@ -272,7 +272,7 @@ static inline BOOL _ASDisplayNodeIsAncestorOfDisplayNode(ASDisplayNode *possible
   }
 }
 
-extern UIView * _Nullable ASFindClosestViewOfLayer(CALayer *layer)
+AS_EXTERN UIView * _Nullable ASFindClosestViewOfLayer(CALayer *layer)
 {
   while (layer != nil) {
     if (UIView *view = ASDynamicCast(layer.delegate, UIView)) {
@@ -283,7 +283,7 @@ static inline BOOL _ASDisplayNodeIsAncestorOfDisplayNode(ASDisplayNode *possible
   return nil;
 }
 
-extern ASDisplayNode *ASDisplayNodeFindClosestCommonAncestor(ASDisplayNode *node1, ASDisplayNode *node2)
+AS_EXTERN ASDisplayNode *ASDisplayNodeFindClosestCommonAncestor(ASDisplayNode *node1, ASDisplayNode *node2)
 {
   ASDisplayNode *possibleAncestor = node1;
   while (possibleAncestor) {
@@ -297,7 +297,7 @@ static inline BOOL _ASDisplayNodeIsAncestorOfDisplayNode(ASDisplayNode *possible
   return possibleAncestor;
 }
 
-extern ASDisplayNode *ASDisplayNodeUltimateParentOfNode(ASDisplayNode *node)
+AS_EXTERN ASDisplayNode *ASDisplayNodeUltimateParentOfNode(ASDisplayNode *node)
 {
   // node <- supernode on each loop
   // previous <- node on each loop where node is not nil

Source/ASExperimentalFeatures.h

@@ -14,7 +14,6 @@
 #import <AsyncDisplayKit/ASBaseDefines.h>
 
 NS_ASSUME_NONNULL_BEGIN
-ASDISPLAYNODE_EXTERN_C_BEGIN
 
 /**
  * A bit mask of features. Make sure to update configuration.json when you add entries.
@@ -31,10 +30,9 @@ typedef NS_OPTIONS(NSUInteger, ASExperimentalFeatures) {
 };
 
 /// Convert flags -> name array.
-NSArray<NSString *> *ASExperimentalFeaturesGetNames(ASExperimentalFeatures flags);
+AS_EXTERN NSArray<NSString *> *ASExperimentalFeaturesGetNames(ASExperimentalFeatures flags);
 
 /// Convert name array -> flags.
-ASExperimentalFeatures ASExperimentalFeaturesFromArray(NSArray<NSString *> *array);
+AS_EXTERN ASExperimentalFeatures ASExperimentalFeaturesFromArray(NSArray<NSString *> *array);
 
-ASDISPLAYNODE_EXTERN_C_END
 NS_ASSUME_NONNULL_END