xref: /aosp_15_r20/external/compiler-rt/test/tsan/fd_stdout_race.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 X;
8*7c3d14c8STreehugger Robot 
Thread1(void * x)9*7c3d14c8STreehugger Robot void *Thread1(void *x) {
10*7c3d14c8STreehugger Robot   barrier_wait(&barrier);
11*7c3d14c8STreehugger Robot   int f = open("/dev/random", O_RDONLY);
12*7c3d14c8STreehugger Robot   char buf;
13*7c3d14c8STreehugger Robot   read(f, &buf, 1);
14*7c3d14c8STreehugger Robot   close(f);
15*7c3d14c8STreehugger Robot   X = 42;
16*7c3d14c8STreehugger Robot   return NULL;
17*7c3d14c8STreehugger Robot }
18*7c3d14c8STreehugger Robot 
Thread2(void * x)19*7c3d14c8STreehugger Robot void *Thread2(void *x) {
20*7c3d14c8STreehugger Robot   X = 43;
21*7c3d14c8STreehugger Robot   write(STDOUT_FILENO, "a", 1);
22*7c3d14c8STreehugger Robot   barrier_wait(&barrier);
23*7c3d14c8STreehugger Robot   return NULL;
24*7c3d14c8STreehugger Robot }
25*7c3d14c8STreehugger Robot 
main()26*7c3d14c8STreehugger Robot int main() {
27*7c3d14c8STreehugger Robot   barrier_init(&barrier, 2);
28*7c3d14c8STreehugger Robot   pthread_t t[2];
29*7c3d14c8STreehugger Robot   pthread_create(&t[0], NULL, Thread1, NULL);
30*7c3d14c8STreehugger Robot   pthread_create(&t[1], NULL, Thread2, NULL);
31*7c3d14c8STreehugger Robot   pthread_join(t[0], NULL);
32*7c3d14c8STreehugger Robot   pthread_join(t[1], NULL);
33*7c3d14c8STreehugger Robot }
34*7c3d14c8STreehugger Robot 
35*7c3d14c8STreehugger Robot // CHECK: WARNING: ThreadSanitizer: data race
36*7c3d14c8STreehugger Robot // CHECK:   Write of size 4
37*7c3d14c8STreehugger Robot // CHECK:     #0 Thread1
38*7c3d14c8STreehugger Robot // CHECK:   Previous write of size 4
39*7c3d14c8STreehugger Robot // CHECK:     #0 Thread2
40*7c3d14c8STreehugger Robot 
41*7c3d14c8STreehugger Robot 
42