// RUN: %clang_tsan %s -o %t -framework Foundation // RUN: %deflake %run %t 2>&1 | FileCheck %s #import #import "../test.h" dispatch_queue_t queue; dispatch_data_t data; dispatch_semaphore_t sem; const char *path; long my_global = 0; int main(int argc, const char *argv[]) { fprintf(stderr, "Hello world.\n"); print_address("addr=", 1, &my_global); barrier_init(&barrier, 2); queue = dispatch_queue_create("my.queue", DISPATCH_QUEUE_CONCURRENT); sem = dispatch_semaphore_create(0); NSString *ns_path = [NSTemporaryDirectory() stringByAppendingPathComponent:[NSString stringWithFormat:@"temp-gcd-io.%d", getpid()]]; path = ns_path.fileSystemRepresentation; NSData *ns_data = [NSMutableData dataWithLength:1000]; data = dispatch_data_create(ns_data.bytes, ns_data.length, NULL, DISPATCH_DATA_DESTRUCTOR_DEFAULT); dispatch_io_t channel = dispatch_io_create_with_path(DISPATCH_IO_STREAM, path, O_CREAT | O_WRONLY, 0666, queue, ^(int error) { }); if (! channel) abort(); dispatch_io_set_high_water(channel, 1); dispatch_io_write(channel, 0, data, queue, ^(bool done, dispatch_data_t remainingData, int error) { if (error) abort(); my_global = 42; barrier_wait(&barrier); }); dispatch_io_barrier(channel, ^{ barrier_wait(&barrier); my_global = 43; dispatch_semaphore_signal(sem); }); dispatch_semaphore_wait(sem, DISPATCH_TIME_FOREVER); dispatch_io_close(channel, 0); fprintf(stderr, "Done.\n"); return 0; } // CHECK: Hello world. // CHECK: addr=[[ADDR:0x[0-9,a-f]+]] // CHECK: WARNING: ThreadSanitizer: data race // CHECK: Location is global 'my_global' {{(of size 8 )?}}at [[ADDR]] (gcd-io-barrier-race.mm.tmp+0x{{[0-9,a-f]+}}) // CHECK: Done.