1// This test verifies that dispatch_sync() doesn't actually copy the block under TSan (without TSan, it doesn't).
2
3// RUN: %clang_tsan %s -o %t_no_tsan   -framework Foundation -fno-sanitize=thread
4// RUN: %clang_tsan %s -o %t_with_tsan -framework Foundation
5
6// RUN: %run %t_no_tsan   2>&1 | FileCheck %s
7// RUN: %run %t_with_tsan 2>&1 | FileCheck %s
8
9#import <Foundation/Foundation.h>
10
11@interface MyClass : NSObject
12@end
13
14@implementation MyClass
15- (instancetype)retain {
16  // Copying the dispatch_sync'd block below will increment the retain count of
17  // this object. Abort if that happens.
18  abort();
19}
20@end
21
22int main(int argc, const char* argv[]) {
23  dispatch_queue_t q = dispatch_queue_create("my.queue", NULL);
24  id object = [[MyClass alloc] init];
25  void (^block)(void) = ^ {
26    NSLog(@"%@", object);
27  };
28  dispatch_sync(q, ^{
29    NSLog(@"%@", object);
30  });
31  dispatch_sync(q, block);
32  [object release];
33  NSLog(@"Done.");
34  return 0;
35}
36
37// CHECK: Done.
38// CHECK-NOT: WARNING: ThreadSanitizer
39