xref: /aosp_15_r20/external/compiler-rt/test/tsan/race_on_write.cc (revision 7c3d14c8b49c529e04be81a3ce6f5cc23712e4c6)
1*7c3d14c8STreehugger Robot // RUN: %clangxx_tsan -O1 %s -o %t && %deflake %run %t | FileCheck %s
2*7c3d14c8STreehugger Robot #include "test.h"
3*7c3d14c8STreehugger Robot #include <sys/types.h>
4*7c3d14c8STreehugger Robot #include <sys/stat.h>
5*7c3d14c8STreehugger Robot #include <fcntl.h>
6*7c3d14c8STreehugger Robot 
7*7c3d14c8STreehugger Robot int fd;
8*7c3d14c8STreehugger Robot char buf;
9*7c3d14c8STreehugger Robot 
Thread1(void * x)10*7c3d14c8STreehugger Robot void *Thread1(void *x) {
11*7c3d14c8STreehugger Robot   buf = 1;
12*7c3d14c8STreehugger Robot   barrier_wait(&barrier);
13*7c3d14c8STreehugger Robot   return NULL;
14*7c3d14c8STreehugger Robot }
15*7c3d14c8STreehugger Robot 
Thread2(void * x)16*7c3d14c8STreehugger Robot void *Thread2(void *x) {
17*7c3d14c8STreehugger Robot   write(fd, &buf, 1);
18*7c3d14c8STreehugger Robot   return NULL;
19*7c3d14c8STreehugger Robot }
20*7c3d14c8STreehugger Robot 
main()21*7c3d14c8STreehugger Robot int main() {
22*7c3d14c8STreehugger Robot   barrier_init(&barrier, 2);
23*7c3d14c8STreehugger Robot   fd = open("/dev/null", O_WRONLY);
24*7c3d14c8STreehugger Robot   if (fd < 0) return 1;
25*7c3d14c8STreehugger Robot   pthread_t t[2];
26*7c3d14c8STreehugger Robot   pthread_create(&t[0], NULL, Thread1, NULL);
27*7c3d14c8STreehugger Robot   barrier_wait(&barrier);
28*7c3d14c8STreehugger Robot   pthread_create(&t[1], NULL, Thread2, NULL);
29*7c3d14c8STreehugger Robot   pthread_join(t[0], NULL);
30*7c3d14c8STreehugger Robot   pthread_join(t[1], NULL);
31*7c3d14c8STreehugger Robot   close(fd);
32*7c3d14c8STreehugger Robot }
33*7c3d14c8STreehugger Robot 
34*7c3d14c8STreehugger Robot // CHECK: WARNING: ThreadSanitizer: data race
35*7c3d14c8STreehugger Robot // CHECK:   Read of size 1
36*7c3d14c8STreehugger Robot // CHECK:     #0 write
37*7c3d14c8STreehugger Robot // CHECK:   Previous write of size 1
38*7c3d14c8STreehugger Robot // CHECK:     #0 Thread1
39