xref: /llvm-project/compiler-rt/test/tsan/fd_stdout_race.cpp (revision bcaeed49cb063de9fe504aa29e1cadff8a7be710)
1*bcaeed49SFangrui Song // RUN: %clangxx_tsan -O1 %s -o %t && %deflake %run %t | FileCheck %s
2*bcaeed49SFangrui Song #include "test.h"
3*bcaeed49SFangrui Song #include <sys/types.h>
4*bcaeed49SFangrui Song #include <sys/stat.h>
5*bcaeed49SFangrui Song #include <fcntl.h>
6*bcaeed49SFangrui Song 
7*bcaeed49SFangrui Song int X;
8*bcaeed49SFangrui Song 
Thread1(void * x)9*bcaeed49SFangrui Song void *Thread1(void *x) {
10*bcaeed49SFangrui Song   barrier_wait(&barrier);
11*bcaeed49SFangrui Song   int f = open("/dev/random", O_RDONLY);
12*bcaeed49SFangrui Song   char buf;
13*bcaeed49SFangrui Song   read(f, &buf, 1);
14*bcaeed49SFangrui Song   close(f);
15*bcaeed49SFangrui Song   X = 42;
16*bcaeed49SFangrui Song   return NULL;
17*bcaeed49SFangrui Song }
18*bcaeed49SFangrui Song 
Thread2(void * x)19*bcaeed49SFangrui Song void *Thread2(void *x) {
20*bcaeed49SFangrui Song   X = 43;
21*bcaeed49SFangrui Song   write(STDOUT_FILENO, "a", 1);
22*bcaeed49SFangrui Song   barrier_wait(&barrier);
23*bcaeed49SFangrui Song   return NULL;
24*bcaeed49SFangrui Song }
25*bcaeed49SFangrui Song 
main()26*bcaeed49SFangrui Song int main() {
27*bcaeed49SFangrui Song   barrier_init(&barrier, 2);
28*bcaeed49SFangrui Song   pthread_t t[2];
29*bcaeed49SFangrui Song   pthread_create(&t[0], NULL, Thread1, NULL);
30*bcaeed49SFangrui Song   pthread_create(&t[1], NULL, Thread2, NULL);
31*bcaeed49SFangrui Song   pthread_join(t[0], NULL);
32*bcaeed49SFangrui Song   pthread_join(t[1], NULL);
33*bcaeed49SFangrui Song }
34*bcaeed49SFangrui Song 
35*bcaeed49SFangrui Song // CHECK: WARNING: ThreadSanitizer: data race
36*bcaeed49SFangrui Song // CHECK:   Write of size 4
37*bcaeed49SFangrui Song // CHECK:     #0 Thread1
38*bcaeed49SFangrui Song // CHECK:   Previous write of size 4
39*bcaeed49SFangrui Song // CHECK:     #0 Thread2
40*bcaeed49SFangrui Song 
41*bcaeed49SFangrui Song 
42