| // RUN: %clang_tsan %s -o %t -undefined dynamic_lookup |
| // RUN: %run %t 2>&1 | FileCheck %s --implicit-check-not='ThreadSanitizer' |
| |
| #include "dispatch/dispatch.h" |
| |
| #include <stdio.h> |
| |
| // Allow compilation with pre-macOS 10.14 (and aligned) SDKs |
| API_AVAILABLE(macos(10.14), ios(12.0), tvos(12.0), watchos(5.0)) |
| DISPATCH_EXPORT DISPATCH_NONNULL_ALL DISPATCH_NOTHROW |
| void dispatch_async_and_wait(dispatch_queue_t queue, |
| DISPATCH_NOESCAPE dispatch_block_t block); |
| |
| long global; |
| |
| int main() { |
| // Guard execution on pre-macOS 10.14 (and aligned) platforms |
| if (dispatch_async_and_wait == NULL) { |
| fprintf(stderr, "Done.\n"); |
| return 0; |
| } |
| |
| dispatch_queue_t q = dispatch_queue_create("my.queue", DISPATCH_QUEUE_SERIAL); |
| dispatch_semaphore_t s = dispatch_semaphore_create(0); |
| |
| // Force queue to context switch onto separate thread. |
| dispatch_async(q, ^{ |
| dispatch_semaphore_wait(s, DISPATCH_TIME_FOREVER); |
| }); |
| dispatch_semaphore_signal(s); |
| |
| global++; |
| dispatch_async_and_wait(q, ^{ |
| // The queue continues to execute on separate thread. This would cause a |
| // race if we had used `dispatch_async()` without the `_and_wait` part. |
| global++; |
| }); |
| global++; |
| |
| fprintf(stderr, "Done.\n"); |
| return 0; |
| } |
| |
| // CHECK: Done. |