1// RUN: %clang_tsan %s -o %t
2// RUN: %deflake %run %t 2>&1 | FileCheck %s
3
4#include <dispatch/dispatch.h>
5
6#include "../test.h"
7
8dispatch_queue_t queue;
9dispatch_data_t data;
10dispatch_semaphore_t sem;
11const char *path;
12
13long my_global = 0;
14
15int main(int argc, const char *argv[]) {
16 fprintf(stderr, format: "Hello world.\n");
17 print_address("addr=", 1, &my_global);
18 barrier_init(barrier: &barrier, count: 2);
19
20 queue = dispatch_queue_create("my.queue", DISPATCH_QUEUE_CONCURRENT);
21 sem = dispatch_semaphore_create(0);
22 path = tempnam(NULL, pfx: "libdispatch-io-race");
23 char buf[1000];
24 data = dispatch_data_create(buf, sizeof(buf), NULL, DISPATCH_DATA_DESTRUCTOR_DEFAULT);
25
26 dispatch_io_t channel = dispatch_io_create_with_path(DISPATCH_IO_STREAM, path, O_CREAT | O_WRONLY, 0666, queue, ^(int error) { });
27 if (! channel) abort();
28 dispatch_io_set_high_water(channel, 1);
29
30 dispatch_io_write(channel, 0, data, queue, ^(bool done, dispatch_data_t remainingData, int error) {
31 my_global = 42;
32 barrier_wait(barrier: &barrier);
33 });
34
35 dispatch_io_write(channel, 0, data, queue, ^(bool done, dispatch_data_t remainingData, int error) {
36 barrier_wait(barrier: &barrier);
37 my_global = 42;
38
39 dispatch_semaphore_signal(sem);
40 });
41
42 dispatch_semaphore_wait(sem, DISPATCH_TIME_FOREVER);
43 dispatch_io_close(channel, 0);
44
45 fprintf(stderr, format: "Done.\n");
46 return 0;
47}
48
49// CHECK: Hello world.
50// CHECK: addr=[[ADDR:0x[0-9,a-f]+]]
51// CHECK: WARNING: ThreadSanitizer: data race
52// CHECK: Location is global 'my_global' {{(of size 8 )?}}at [[ADDR]] (io-race.c.tmp+0x{{[0-9,a-f]+}})
53// CHECK: Done.
54

source code of compiler-rt/test/tsan/libdispatch/io-race.c