1#import <Foundation/Foundation.h> 2#if __has_include(<AppKit/AppKit.h>) 3#import <AppKit/AppKit.h> 4#define XXView NSView 5#else 6#import <UIKit/UIKit.h> 7#define XXView UIView 8#endif 9 10int main() { 11 XXView *view = [[XXView alloc] init]; 12 dispatch_group_t g = dispatch_group_create(); 13 dispatch_group_enter(g); 14 [NSThread detachNewThreadWithBlock:^{ 15 @autoreleasepool { 16 [view superview]; 17 } 18 dispatch_group_leave(g); 19 }]; 20 dispatch_group_wait(g, DISPATCH_TIME_FOREVER); 21} 22